Panterra Scooter Derestricting Guide

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Panterra Scooter Derestricting Guide

Postby 4Strokes » Thu Jun 02, 2016 10:32 am

Topic: Guide to derestricting Panterra scooters
Author: pranakhan
Posted: 07/11/2005 10:29:47 AM

THE DEFINITIVE GUIDE TO GETTING PANTERRA SCOOTERS TO GO FASTER
I bought a red Panterra Fusion 50cc scooter a year ago and was so completely disgusted by its performance that I left it in the garage for a while. I could only get to 20-25 downhill with a good tailwind, and on some hills I couldn't go more than 10. It was embarrassing.

After doing a ton of research, my scooter now easily goes 35-40 on a straight away, and 45-50 on slight downhills. That hill that made me to go 10? I can cruise up that one at 25 now!

I've read a lot of crap advice on what to do about making these faster. I decided to post a definitive guide to derestricting 50cc panterra scooters so everyone else can have as much fun as I am having with mine. I actually ride my scooter 10 miles to work everyday in traffic, and I get to work in 30 minutes, the same time it took in my car, but this is a lot more fun!

Ok so down to business.

PANTERRA 50CC TECH SPECIFICATIONS
Ok, so our scooters have crappy manuals and no support. Therefore, it REALLY helps to understand what kind of engine is in that puppy.

From what I have learned, Nikota, a tool and machining company, purchased a set of old model molds and dies from Honda. These molds and dies, with a few modifications, are what they used to make the engine and other important parts on the scooter. A select few parts on the scooter are made by OEMs. It is for this reason that you can purchase Honda CRF70 engine parts and fit them onto your scooter. the engine is basically a 72CC Honda engine that has been modified to shorten the stroke so that it only displaces 50cc. What does this mean?

  1. You are not out on parts, you can either make stock Honda CRF70 parts work, or you can generally make them work with little effort.
     
  2. You can get an aftermarket "Big Bore" kit for this engine and make it displace up to 125cc. (I'm thinking of trying to install a Honda XR70/CRF70 Big Bore kit, they are pricey, but not as pricey as a new scooter!)
Regardless, if you need to work on your engine, and since its hard to find service manuals for these, it would be good if you knew GENERALLY what the scooter configuration was so you could look-up how it all works on Wikipedia and such. The Panterra Fusion and Metro scooters are exactly the same, only differing in body plastic.

  • a. 72cc 4-stroke air-cooled engine, bored down to displace 49cc, to keep it legal as a moped. ~10:1 Compression Ratio.
  • b. Variable Choke (constant depression) carburetor w/ diaphragm chamber.
  • c. Continuously Variable Transmission (CVT) (the automatic transmission)
And that's basically all the important parts, the rest is just dressing on the cake.

VROOM VROOM, MAKING IT GO FASTER!
Here is the fun part... After completely disassembling my engine, I found that it has absolutely none of the restrictions shown on other sites, like in the intake, exhaust, and transmission. There is no washer in the CVT, no gaskets in the airbox, nothing. Those other derestricting sites are for European scooters and those kinds of restrictions aren't used here in the US. So forget those.

The engine is restricted in 3 places, period.
  1. The air intake is restricted by the ridiculously thick foam "air filter", a.k.a. engine strangler.
  2. The exhaust is only slightly restricting the engine.
  3. The transmission is loaded with hideously heavy roller weights.
We'll address these one at a time, and what you can expect.

AIR FILTER
The air filter is restricting the intake. This means that your engine can't get as much air as it needs. A lot of people think that twisting the throttle opens up a fuel valve and pushes more fuel in, but that's incorrect. Twisting the throttle opens up an air valve to let more air into the engine. The natural vacuum created by moving air actually pulls fuel into the airflow in the carburetor. If the engine can't suck in a lot of air, it will run slower and weaker. There are a couple of ways to get around this.

  1. Open the airbox (the plastic box on the left side of the rear wheel.) and rip that mother out, then reassemble the airbox. Now you are running without a filer. This can damage the engine sure, but these bikes pull air in through the FRAME, and the air inlets on the frame are placed high up away from the road. Running without a filter will probably reduce the total mileage your engine can go before dieing, but its an ok temporary fix since the air inlets wont be picking up any large debris, just slight dust.
     
  2. Open the airbox, rip the mother out, and put in a high performance K&M (or other brand) filter. You wont be able to find one that fits perfectly. You'll need to take that ugly foam POS into your friendly neighborhood scooter dealer/shop (most cities have a couple of these) and they will find an air filter that is roughly the same size. You'll need to cut it up to fit into the airbox. This is the best method.
Now that you have derestricted your air flow, here is what you should notice: acceleration is MUCH better, the engine is more responsive, and it feels more powerful. That's it! Don't expect an increase in the scooters top speed, just an increase it how long it takes to get it there. Also, if you are having problems getting up steep hills, you'll find that this significantly fixes that.

DERESTRICTING THE EXHAUST
The pipe is not really restricted, but could be better tuned. You will not be able to find an aftermarket performance pipe that will fit. If you take the pipe off your bike you won't find restrictor cones or anything else. The stock pipe is fine, just not optimal. Now, here are the best ways to fix that. Mind you, I was getting 35-45 out of this bike without modding the exhaust, but I know that modding the exhaust will give a reasonable boost in power. Ok so, how is it restricting the engine?

Do you see that short little pipe that comes off the back end of the exhaust? Do you see the longer pipe that feeds the exhaust? The pipe coming in to the exhaust is wider than the exit pipe. This creates more back pressure than is necessary for the engine. Exhaust pipe size and such are more critical on 2 stroke engines, but we have 4 stroke engines so its a bit different. The circumference of the pipe coming out of the engine is ~4.0" and the circumference of the output pipe is ~2.0". Make the output capacity match the input capacity.

There are two things that will help with the exhaust:
  1. Drilling 1 or more 1/2" holes into the back (end cap) of the pipe. I've drilled two of them and the bike runs a bit better and sounds lovely, see the thread below. It looks like you won't hurt a thing if you just drill two holes. I will likely go to three soon. If you accidentally punch too many holes into the pipe you can plug them with 1/2" machine screws from your local hardware store and even take the pipe back to stock using those screws, for safety.
     
    AND/OR
     
  2. Opening up the pipe and removing the baffles inside.
     
    Option 2 will be a bitch. Cutting off the back of the pipe is simple, just use a hacksaw and an afternoon. Putting the end you cut off back onto the pipe after removing the baffles, not so simple. I looked into the drilled holes using a bright light and I couldn't SEE any kind of baffle inside the pipe. Does this bike even have them?
Remember, I got 35-45 out of my Fusion BEFORE I touched the pipe, so if you are uncomfortable doing any of the above you'll still get good speed!

DERESTRICTING THE TRANSMISSION
This is the part that you will notice the biggest difference overall. You see, your engine is RPM restricted, meaning, it can only run so fast before it wont rev up past that point. What does this do to you?

  1. The back wheel is engaged by the engine through a "centrifugal clutch". This is a device that increases the engagement of the wheel as the RPMs increase. If the RPMs are limited, it takes longer for the clutch to engage the wheel, and you accelerate slower.
     
  2. Your top speed is affected. If the engine can only spin a certain speed, then you can only go a certain speed.
The transmission restriction is the heart of it all. This is why you move like gelatinous goo on a cold day. And this is how to fix it:

  1. Replace the roller weights with new, much lighter ones.
  2. Possibly, install a stiffer clutch spring.
And here is how:

  1. The transmission is on the left side of the bike under the airbox where the kick starter is. You need to remove the cover of the CVT by simply taking 8 bolts out.
     
  2. The CVT is sealed with a gasket, and likely, even tho you have the bolts off, its not budging. Simple fix, take the rubber hose off the front of the CVT, put the claw of a hammer into the hole, and pull, it will come off.
     
  3. Now you can see two "wheels" inside. The one at the front is the "variator" and the one at the back is the "centrifugal clutch." A rubber belt connects the two.
     
  4. You need to remove the variator, and this part is very very hard. It is attached to the drive shaft coming out of the engine, and it will spin when you try to take the bolt off. If you are lucky enough to have an impact wrench, then getting the bolt off is very easy. If you are like most people and don't have one you will need to halt the motion of the variator so that you can get the bolt off. Luckily, the variator has a sprocket on it that is driven by the electric starter. The secret is in jamming the sprocket with something hard and unbendable. I used one side of a scissors with the edge inside the sprocket and the other jammed against the starter gear, and it popped right off. (You electric starter is driving that small set of sprockets near the top of the variator. It's gears mesh with the drive shaft sprocket and turns the engine. You'll also see that the kickstarter works in roughly the same way, by spinning the driveshaft.)
     
  5. The variator will slide out off the driveshaft. It is actually several pieces so be careful and take note how to goes back together. Its pretty straightforward.
     
  6. The roller weights are housed on the back side of the variator, inside the silver wheel. There is a movable plate behind that wheel which you slide out to reveal the weights, which look like little rubber wheels.
     
  7. Take one of the weights to your friendly neighborhood scooter store and ask them for 6 gram weights. They're $12-$15 a set.
     
  8. Take your pretty little rollers home and replace the stock ones, and reassemble the CVT.
     
  9. Be very very careful about making sure the bolt that holds the variator to the driveshaft is on DAMN TIGHT! On mine, I didn't have it tight enough and it came apart during testing, making an awful, horrible, gut-wrenching, grinding noise that did absolutely no damage to my bike. Just make sure its as tight as you can get it and use Lok-Tite (the removable kind) if you have it.
The lighter weights allow your engine to rap up to higher RPMs. It actually keeps the gear ratio for the drive gear lower. Now you'll notice a major significant increase in acceleration and top speed! Impressive huh? It was primarily all in the weights, that was the only thing that made you slow!

Remember, the secret is IN THE WEIGHTS! After putting in the lighter weights I had a great top end speed but not so good acceleration from a stop. My local scooter shop told me it was due to the lack of engine power for the light weights, but that I could probably fix it by installing a stiffer clutch spring in the back without adjusting the weight. If the new clutch spring didn't work, I could go up in weight in 1/2gram steps until I found the right balance between power and speed. I'll install the clutch spring this week, and let you know what was optimal for me.

The acceleration isn't THAT bad however, I am able to ride my fusion 10 miles each way to work in urban traffic now!

OTHER IMPORTANT THINGS THAT MAKE IT RUN BETTER
I found several other things that are very important that were not in the damn manual.

  1. The tires were low when you bought it. Very very low. Check the tire pressure. Low tires drag and make it slower.
     
  2. The front wheel was mounted LOOSE! I couldn't believe it, I found that the front axle had an inch of play in it!!! The scooter was squirrely at 35mph and that was why. I tightened that down and got significantly better handling and speed, not to mention, probably saved my own ass. Check ALL the bolts everywhere!
     
  3. The bike is shipped with very low quality "shipping oil." Change the oil! This is simple, just undo the screw on that bottom of the engine next to where you check the oil, let it all drain out, put it back in, and fill it up with 4-cycle motorcycle oil OR plain motor oil that is 10W-30 or 10W-40. It takes around 800ml to fill up.
     
  4. I thought it just needed the lowest grade of fuel, but I was wrong. It runs best on PREMUIM/SUPER (90+ octane) grade. Lower octane fuels will detonate when the engine gets hot. You can safely use Octane Booster additives in your fuel, even if its already premium. To determine how much octane booster to add, use this formula:
     
    y = (o / 20) * s
     
    Where:
    • y - is the amount of booster to add, measured in whatever units are on the bottle (ml, oz, etc).
    • o - is the amount of booster contained in the FULL bottle, as read off the label, in any measurement unit. (ml, oz, etc)
    • s - is the total capacity of your scooter's gas tank. (For the Panterra Fusion, its ~2 gallons, so use 2)
     
    So, if the bottle says it contains 15ml of booster, you would do this:
     
    1.5 = (15 / 20) * 2
     
    Add 1.5ml of booster to your tank! HELL, add 2ml!!
FIN!

Note: I live in Denver which is at ~5300 feet in elevation. That altitude significantly affects engine performance. My bike has less power here than it would at a much lower altitude. You guys may find it runs best on heavier (or lighter) weights (start at 6). Experiment! These bikes are actually not bad in quality, and the engine is tough as all hell. I should know, I've taken it all the way apart! :-)

These aren't bad bikes at all! I paid $700 for mine at Pep Boys and it now is just as quick, if not slightly quicker than, an $1800 Honda Metro. I bet when I finish the exhaust and the 5 gram weights/clutch springs, I'll be hitting 50 on flats! who wants to bet?

I see a lot of people ask for help for the same questions. "How do I make my X go faster?!?", right after someone posts a guide like this one, because their scooter may be a slightly different brand and what not. You should know that basically ALL scooters are configured the SAME! You can do the stuff outlined in this document on pretty much ANY scooter, and they will work! Learn how engines work, and you can apply the knowledge to any brand. Wikipedia rules!

I test drove a 150cc Derbi Boulevard this weekend! Oh my GOD it was hot! They said it was $3000, but I bet I can find it for less. I will be buying that one soon, and giving my panterra to my son.

I ride my Fusion 20 miles a day in city traffic, no problems. FUN!

SCOOT Time!

Reply by Lew on 07/11/2005 4:00:46 PM
Awesome post, Pranakhan! I'll call around to some cycle shops to look for the rollers -- I can't think of any "scooter" stores around Detroit. If anyone finds an online source, I would think this would be a great thread to post that URL. Thanks for taking the time to write that out in such detail.

Reply by pranakhan on 07/11/2005 4:11:49 PM
No problem! I bet you are like me and desperate to find good info out there thats not written by hurried teens! I just modified the post to provide some stuff but try this:

To get the rollers you could order them from my scooter shop here in Denver, Sportique Scooters. Its a great shop, very supportive of all scooter owners, and always reasonable. We need a Panterra owners scooter club too!

Reply by polaris700 on 07/11/2005 4:41:16 PM
let us no what you are going to do to the exhaust and what ever else. how do you put on roller weights

Reply by Lew on 07/11/2005 10:25:57 PM
I have some space at my blog domain (Ripping Stitches -- don't be easily offended, most of the junk is totally tongue-in-cheek, 7th grade humor) and I was thinking of adding a PHP subdomain for Panterra info specifically. With all props (how "street of me") this forum is the best I've found which even includes the Nikota stock. If I get it together over the next few weeks, I'll be sure to post the URL here.

Reply by pranakhan on 07/11/2005 10:38:49 PM
Tonight I modded the stock exhaust on my Fusion 50cc. SUHWEET!

The result: No increase in top speed. Definately an increase in power up hills, slight increase in acceleration, and now the bike sounds WICKED! A nice low throaty rumbling note.

Analysis: Definately, this leads me to believe (and it makes sense) that the secret to acceleration and top speed is primarily the gearing in the CVT, and is less affected by total engine output. Definately, modding the pipe increased power by a nominal amount (everybit counts) but I'm going to go back to looking into the CVT for more performance.

How do do it: I drilled the end cap on the pipe, thats it. Now, I started this conservatively. I made a change, tested it, made another, tested it, etc.

I started with a single hole. You'll need a drill, a 1/2" drill bit, and a smaller one, 1/8" or 1/4". I drilled a small hole using the smaller bit right above the small downturned pipe coming out of the exhaust. Remember, use a strong constant pressure on the drill at about half the RPM. Run the drill too fast it gets hot and wont cut as well. Once you puncture the smaller hole, then widen it with the 1/2" bit. Done. Try it out, different altitudes and such will affect how this will work. You may be happy with just one. i wasn't...

So I drilled another hole directly to the right of the center pipe using the same technique. I took it for a roll and it sounded totally sweet and ran well.

These engines need a certain amount of back pressure from the pipe to operate correctly so I stopped at 2. I may try a third, so let me explain the reasoning behind the 1/2" hole.

You can plug it with a 1/2" machine screw! So, if you acidentally punch too many holes in your pipe, you can take it back to stock by plugging the hole with a 1/2" machine screw, so you dont screw up your exhaust system by experimenting with it.

Be careful not to get many metal slivers into the pipe. I dont know what that could do if it ended up in the engine.

My bike has an RPM plateau thats been there after I switched the roller weights. Its only there from a dead stop, and its worse if starting up hill. It doesnt exist while rolling or starting down hill. When I open up to full throttle, the RPMs kick up a bit and the bike starts to move, but then they hold about mid way in the range for a couple seconds, then suddenly kick up to full giving full power. I think this has something to do with the CVT, I think I may need to put in 3 heavier wheights to bring me up partially. (you can mix two different weights of rollers by putting in 3 of each, interlaced [1 then 2 then 1 then 2 etc) to balance them out.

I'll keep y'all posted! What a great board! If you make this exhaust mod, let me know what your results are! I want to develop an even more defintive guide!

SCOOT forever!

Reply by pranakhan on 07/12/2005 11:36:35 AM
I rode my bike with modded pipe to work again today. I'm travelling 10 miles each way in urban traffic, on streets where the average limit is 30mph. In the mornings I have no problem keeping up with traffic.

I noticed last night on the way home that my bikes power had crapped out a fair amount, tho it was still definately performing better than it did all stock. Anyway, it was the heat of the day. Last night it got to around 95-100 degrees with massive heat waves coming up off the pavement. My bike runs smoother and faster in the cool morning air.

Hot air is less dense than cold air. The engine will try to suck in a fixed volume of air, and if the air is less dense then it will pull in less fuel, and it will loose power, just as if the air intake was slightly restricted. I'm hoping the new pipe mod will allow it to move a bit more air in the heat than last night and help me regain some lost performance from the heat. We'll see.

I have an update regarding the poor acceleration performance on my bike from a stop. If you read above you'll see that although I gained a nice top end speed, I have some kind of RPM plateau when going full throttle from a full stop. Well... my suspicions were correct!

I had a conversation this morning with my friendly neighborhood scooter shop's repair guys. After describing to them the situation, they told me that the issue is the lighter roller weights in the variator. They said that since I stuck those on an engine with the stock cylinder/etc that the engine didn't have quite enough power to throw the weights around. They told me that the secret to this was finding the best balance between power (accel.) and speed. I have two options:

  1. Add slightly heavier weights to the variator. I could put in all 6.5 or 7.0gram weights, or mix my 6gram weights with say, 3 7 gram ones. It takes some experimentation to determine the best balance.
     
  2. Leave my lighter weights in the variator but get a stiffer clutch spring.
They recommend that I start with option 2, leaving the lighter weights but stiffening the clutch spring. The stiffer clutch spring will keep the front gear diameter from changing too rapidly, leveling out the grab, smoothing out the RPM increase. They told me that I wont be able to get Panterra specific parts but that I can just bring in my clutch spring and they will find another that fits. I'll let y'all know which part # it ultimately is.

I'll be driving to work tomorrow :-(((( cuz I'm gonna rip the clutch spring out of my bike tonight when I get it home. The scoot shop is less than a mile from where I work so I'll get the new spring tommorow at lunch and install it tommorow night. Keep your fingers crossed! I'm about to finally get the definative GUIDE, including exact part numbers, prices, and where to buy them, to make your Panterra Fusion or Retro practical for REAL transport!

Reply by pranakhan on 07/12/2005 11:40:37 AM
LEW!!! I found a scooter shop in Detroit that will likely have all the parts and advice you need. Give them a try for the roller weights. Pull out your rollers and your airfilter and take them with you to the store. They will find matching rollers and try to find a performance air filter that closely matches your stock one, which you can take home and cut to fit. I'll keep ya posted about the clutch spring.

Reply by polaris700 on 07/12/2005 11:56:53 AM
i live near Detroit to thanks for for that website. its a few miles from my home but its not in Detroit its in Eastpoint, MI. if you can-can you send pics of how you put on the roller weights

Reply by pranakhan on 07/13/2005 09:57:03 AM
polaris700: Yup, tonight I need to tear into the CVT to get the clutch springs. I'll take a slew of photos showing exactly how I did it.

Ok, back to the subject of the loss of power on the hot day. It looks like that has more to do with the grade of fuel I put in than anything else. I've done some extensive research and interviewed some knowledgeable people and its amazing how much the fuel matters, especially on these small engines.

50cc engines are air cooled, and therefore run hotter on a hot day. They also generally run with a high compression ratio. Without having the exact figures to reference I can say that the 50cc 4-strokes we have in the panterra scoots have a compression ratio of ~10:1. Which leads to octane.

The Octane rating of fuel has to do with how the fuel burns in high compression temperatures. Generally, the higher the compression ratio of the engine, the higher the octane you should put in it.

Myths: Premium fuel is more powerful than regular fuel. High octane gas will make you go faster.

Truths: Premium fuel burns the same as regular fuel at low temperatures. As the engine gets hotter, there comes a point where the heat inside the cylinder makes the fuel spontaneously combust BEFORE the spark plug fires. This combustion is incorrectly timed, usually on the upstroke of the piston, so that when the spark plug does fire, the fuel is already partially burnt and wont push down on the piston as hard. This pre-combustion is called "detonation." Detonation will generally make the engine sound like its rattling ("knock" and "ping"). The rattling is actually the sound of the little explosions from the detonation of the fuel.

Higher Octane fuel resists detonation and allows for a more controlled burn. What this means for us is that as our little engines get hotter, the fuel wont start detonating, giving us full power even when we have been riding the scooters hot and hard. My lack of power in the afternoon heat is primarily caused by detonation. Mid grade (87 octane) wasnt enough. The reason why I lost power about half way through my ride was that my engine had finally heated up enough to start causing detonation. Riding the scooters up a hill at full RPM and a slower (20MPH) speed will cause the engine to get pretty darn hot.

Fill your tanks with premium, high octane gas! You wont go faster, but you'll have more reliable power under a wider range of riding conditions.

Can you use Octane Booster additives? YES! Octane boosters are basically Magnesium/Manganese compounds that basically "protect" the fuel inside the chamber from detonation at high temps. Overdosing your fuel with octane booster will generally not harm the engine, but adding excessive amounts wont gain you anything either. To determine how much to add to a FULL tank of your gas use this formula:

y = (o / 20) * s

  • o is the amount of booster the container holds, measured in ANY scale (ml, oz, etc).
  • s is the total fuel capacity of your scooter's gas tank, in gallons.
  • y is The amount of booster to add to the tank. You can just eyeball it if you want, it doesn't have to scientifically precise.
Should you add octane booster to a tank full of premium? It doesn't hurt!

Reply by polaris700 on 07/13/2005 11:08:35 AM
thanks if you are going to post pics. man you no a lot about these scooters.

Reply by pranakhan on 07/13/2005 11:35:43 AM
I'm just posting what I am learning about mine. When I bought it I was hoping to take it to work. It looked a hell of a lot faster than it was and I found out that it was totally impractical to ride to work so it sat in my garage and I felt like I wasted some good money. This summer, I read an article about people who race scooters, and it made me realize that, duh!, I could mod the scooter to make it faster for a lot less than buying a whole new scooter!

To be honest, I knew almost nothing about how engines and transmissions and such work a few weeks ago! I've been spending a lot of time reading on the 'net and asking questions with people who know a hell of a lot more than me, then simply applying the info I learn to our little scooters. All these engines pretty much work the same way, so if you learn about engines in general, you'll learn about the scooters in general as well. Its the theory and it works!

Hey Polaris, what kind of scooter do you have? When did you get it? What do you use it for? Mind if I ask how old you are? Have you tried any of the mods I've written about?

Hmm, actually, why dont all Panterra scooter owners speak up and post answers the above questions! I'm curious to learn about my fellow scooter owners!

Reply by polaris700 on 07/13/2005 12:19:49 PM
I had a 1982 bombardier eagle 2 moped about a year ago until i sold it i use it to race other moped and scooters it had no mods im 17 and about to buy the fusion when i get the money

Reply by pranakhan on 07/13/2005 1:02:17 PM
Our scooters are not dead!!! It looks like the Panterra Fusion 50cc scooters are now being sold as "Wildfire R2 50cc" scooters. Its our scooter exactly, with just a couple minor body style changes! What even cooler is that this Wildfire line is now carrying incredibly inexpensive 150cc versions in both Sport and touring styles. The sport model has a front ABS disc brake, top speed of 55-60mph, and My Big Toy Store is selling them for $1499 SHIPPED!

I think I may get one of these rather than spend $3000 on that Derbi Boulevard 150. I gotta tell ya, after driving a couple 150cc scooters, it makes all of this performance stuff moot, they are a hell of a lot quicker.

Reply by polaris700 on 07/13/2005 1:28:32 PM
for $3000 you can get a Kawasaki Ninja 250R brand new. 0-60 6 seconds, 14.8 quarter mile. thats what was on the internet

Reply by Tonupboy on 07/13/2005 9:47:24 PM
Holy crap! Awesome tips, Pran!! Thanks a whole lot! I can't wait to do the work, Saturday...if what you say works with the Honda Jazz/Metro...then I'm sure they sell aftermarket exhaust too! I've seen one on Japan for the Metro, so who knows if the got copycats in Ebay!

Can you post a pic of your exhaust mod (or all the modifications you did - if you can)??? It would help oh so much!

FYI My next scooter is actually going to be the Stella Scooter (150cc - 2 stroke). This Panterra Retro is going to my wife, lol...who's name is also Stella...I recently just got into the whole scooter craze myself - I rode motorcycles, 500cc and 750cc for 4 years before I discovered what a fun thing scooters really are!!

Reply by pranakhan on 07/13/2005 10:46:34 PM
Hehe, I found a cool scooter that just came out by Tank called the Urban Racer 150. Its a 150cc sweet bike, with front ABS disc brakes, alarm, and remote starter. I dunno how the hell you use an alarm and remote starter on a scooter but it must be cool. Tank is an ISO 9002 certified manufacturing plant so quality shouldn't be too bad. Its a sweet looking scooter too, and I can get it for $1300 shipped to my door. Screw the Derbi, I want this one. With some haggling with the wife I'm gonna be getting this one at the end of the month! I'm so excited. Looks like my 50cc Panterra is also going to my wife! I haven't been able to work on the bike tonight to take photos but I plan on it as soon as I can! I'm going to be dreaming of big, sporty, 65mph 150cc scooters tonight!

Reply by polaris700 on 07/14/2005 1:39:37 PM
i dont no about those tank scooters a kid in the niehgbor hood has one and it is slow it sounds like one of those mini crotch rockets from pepboy if you ever heard them maybe his is a 50cc but im not to sure does tank have a website

Reply by panterra on 07/18/2005 7:50:21 PM
after going to vacation (st maartin) last month im sure any aftermarket exhaust for a scooter will work on ANY scooter. they where all shaft driven, left side kickstart and they all looked like they had same pipes and mounts, since it was a island thats what everyone drove, we also took a boat to st barts, Can you SAY supermoto heaven? there had to have been no cars and all super moto bikes and tons of scooters too.

Reply by scooterchick on 07/25/2005 10:11:40 AM
this is awesome! thank you so much. I bought a fusion for school and i drove it in traffic and my dad said i barely got to 25. I was about to sell it,but now i will do the mods and see how it does.

Reply by panterracrazy on 08/16/2005 10:07:39 AM
is the 49cc yellow panterra a crf 70 to.

Reply by scoot4fun on 08/18/2005 10:22:51 AM
Pranakhan, Great posts! Have you had a chance to play with anymore mods? Did you take any pics? My friends and I found a warehouse in southern California about six months ago that was selling the panterra scooters for $250 ea. We bought about 12 altogether (3 Retro, 4 Fusion, and 5 Freedom). I have played with the carb air mixture screw a little, and it has seemed to help in the higher altitudes of Yosemite ~7000ft. They seemed to run the best at 1 1/2 turns out. Right now they are all pretty comparable on the speeds of about 30-35mph. I am very exited about trying the mods you have posted. Were you able to get any part #'s? Thanks for the great advice.

Reply by Francis101 on 08/19/2005 02:39:26 AM
I had my Panterra about almost a month now I gone many places with it, but it the speed, mile range and charging really bothered me a lot. This is my first moped and I dont know anything about it. The information you giving is good but I dont know anything about gas scooters and how they are structured. If I convert mine to gas what are the things I need? do I need a new back wheel? gas tank? electric starter for the engine? do I still need battery for the engine starter? I just wish there is a shop that converts electric mopeds to gas.

Reply by BMob on 08/27/2005 2:11:34 PM
I have made some of the changes regarding the panterra scooters to my Fusion. It now runs about 50 mph on the flats and 55-60 down a slight hill! My air filter is still stock (used K&N filter oil to keep the dirt from clogging the foam) and I have not even opened the transmission. Not bad considering a 190-lb. rider :-). Another tip I noticed that helps is to use Mobil 1 75/90 gear oil the in the gearbox. Also, try adding a few drops of 10/40 motor oil to the front wheel axle. It makes a big difference in speed. Let me know how things go for your guys. You can find Honda CRF70 Engine Parts: Honda Dirt Bike Schematics (dead link)

Reply by Everest on 09/14/2005 1:38:35 PM
The Honda clone engine used in Panterra is not a 72cc with a shorter stroke. The crank on the 72cc and the 50cc are the same. The 72cc engine just has a larger bore than the 50cc. The Panterra 50cc (49 actually) has a smaller diameter bore and obviously piston than the 72cc (aka Honda 70). The CVT on the Panterras available at pepboys in North Carolina do have a restrictor ring in between the two halves of the front pulley of the CVT. This stop them coming all the way together thus limiting the overall gearing. The radius that the belt has to travel through is smaller giving lower gearing which means more revs are required for any given speed. The restrictor ring in my Panterra meant that at max revs I was getting about 25mph. Once I took the ring out I had about 40mph, with no other mods. I then got a 72cc cylinder and piston from an English salvage yard I found on the internet for I think about $30, I got the carb and manifold from a Honda C90 (the manifold sticks the carb out sideways) I put on a K&N style air filter with a bigger main jet. I also gas flowed the head (polish all ports) and put a megaphone exhaust system on. I changed the vairator weights and the clutch springs. I changed the final drive gearing (it's a shaft and sprocket at the clutch end of the CVT. My top speed is an easy 65mph and it sounds like a 4 stroke dirt bike. It is powerful enough to pull wheelies at 50mph and keep them going for a good mile or more. There were some Panterras that were sold as 50cc, but were actually really the 72cc version. This has happened with several Chinese scooter manufacturers and some have had bikes impounded at the docks in California for that very reason.

Reply by DJ Art on 09/14/2005 10:04:41 PM
Everest, give us some detail on exactly how you did these mods. Does anybody have pics to assist with doing the mods?

Reply by whitelespaul on 09/16/2005 07:01:26 AM
Honda service manual has the pics. XR70.

Reply by DJ Art on 09/20/2005 06:23:17 AM
Can anybody get some pics of how to do the roller weights. I need some kind of guide if i'm going to jump at this project. Something i dont want to mess up is the trans and gearing. So having some pics to judge by would be very nice. Thanks. also some part numbers on the weights andspring would really help. Hard to find any info. Part number would be nice

Reply by Everest on 10/04/2005 7:11:51 PM
On the side of the bike with the kickstart there is a long casing. remove the kickstart then remove the casing (be careful of the gasket, if it has one. Some do and some don't) When you are facing the bike from that side you will see two pulleys. The pulley to the left is the variator. You will need to remove the front half of the pulley. It has a big nut in the middle of it. You will either need a pair of channel locks to hold the pulley still as you undo the not, or better still an impact wrench to loosen the nut. If you try loosening the nut without one of these two things it will simply turn the engine over. Remove the front half of the variator and take out the spacer, a ring or washer that sits on the shift between the two halves of the variator. The restrictor ring sits between the two halves stopping them closing all the way and thus restricting the gearing. reassemble without the ring. remove the carb and cylinder and replace with a 72cc Honda item and the carb from a 90cc Honda. The parts from the 70cc Panterra will work just as well. You want the 90 carb because it is quite a bit bigger. This is a 4 stroke engine, if you are not a good mechanic I would not attempt it (most scooters have 2 stroke engines and are much easier to work on and tune. They have quite a bit more power even when not tuned) 4 strokes are much more difficult to work on. I would only attempt to change the cylinder etc, if you know what you are doing. If you need pictures you probably don't. A small engine mechanic can do it all for you cheaply. ACE Hardware or a lawnmower mechanic. The only part I would try if I didn't really know what I was doing would be the CVT (transmission) restrictor ring. Any Honda 72cc kit will fit they are all the same.

Reply by dafoot on 10/07/2005 05:25:48 AM
I bought a wildfire 50 r2.. Basically followed all the same instructions as the panterra, looked like it was pretty much the same bike. Pulled off the exhaust didn't find any restriction near the exhaust port. Did drill out the rear exit port, didn't increase any sound not sure of any power increase yet. Pulled off the tranny, I didn't find any spacers in between the pulley. Getting about 35-38 top stock, Im 6'4" and 200lbs. Only trouble Im having is from acceleration from stop. Pulled the weights out and they weigh 8.5, but when I measured them they are 16x20, I called Sportique scooters and they dont carry weights that big, biggest they had was 16x17's. Parts guy said those sound like weights for a 150 cc.. anyone know where i can get larger weights from? Also any suggestions on weights that I should use?

Reply by whitelespaul on 10/14/2005 06:12:13 AM
6 gram weights plus stiffer clutch spring.

Reply by dafoot on 10/14/2005 2:28:10 PM
any idea where to get the weights from?

Reply by Kburt on 03/08/2006 05:43:15 AM
I want to say I am impressed with the information you provided on the Panterra 50cc. I was wondering if you know or maybe someone out there might know how to hook up or where to get solar panels for the Panterra Freedom electric Mopeds? This would help retain the power lost driving. If I run up town for something while shopping my scooter will be charging on those nice bright sunny days. Any suggestions would help thanks.

Reply by rufus3939 on 06/12/2006 11:56:25 AM
Anyone know if a fuel shut off valve for the CRF70 will work on the Panterra 50? I need a fuel shut-off valve for Panterra and can't find it. Called Honda and the shut-off valve is 41.99 so was just asking before I ordered. Thanks.

Reply by oceanplexian on 06/30/2006 07:29:40 AM
Errr....solar panels on an electric scooter won't work. Not nearly enough power to make a difference, and no surface to put them on it. I'd also like to know if there's an online source for the roller weights/clutch spring

Reply by jeffm on 07/15/2006 08:49:04 AM
hey... i recently bought the baja sc50 scooter from pepboys...i have heard that this maybe the same scooter as the Panterra Fusion 50cc, does anyone know if thats true?...would these modifications work on it?

also, um...just curious...where is everyone buying all of these 6 gram weights they r putting on the variator? ive called all of my local shops and looked online...seems next to impossible to find for me...

also, does anyone know how to figure out what size they need to be? sorry, im a newbie, and i bought a baja sc50 from a local pepboys...i did a couple of mods to it that i saw in these forums...but it seems like the lighter weights is the real answer for speed. any help would be greatly appreciated. thanks! ;)

Reply by dafoot on 08/04/2006 09:07:24 AM
Ive also been looking for the weights for over a year, noone seems to have them. If anyone finds them let me know

Reply by kinoki on 08/13/2006 8:35:19 PM
this is my first post here, but i printed out this thread a few months ago and i'm finally starting to make some headway.

i've got a panterra retro. i bought one of these - ebay # 150021134732. i took the weights out and they fit. i asked for 5 gram weights. you can specify in your checkout which size you want. i think now i need a stiffer spring to really take advantage of my speed. i also drilled some holes in the muffler - didn't do a lot. and i took out the air filter - also didn't do a lot. the roller weights seem to have done the trick. there's a hill near my house that usually slows me down to about 19 mph. i just barreled up it at 30mph - and that wasn't even full throttle. tomorrow i take it down to the canal tow path and open it up. i'll let you know what my top speed is.

oh yeah, one more thing. getting the belt back on after you've taken the tranny apart is tricky. the pulley on the clutch is actually made up of two plates. if you press them apart the outer plate compresses and you can slip the belt in there. that way you can stretch it fit around the variator bolt. just fyi, to save yourself the frustration i experienced.

i took the retro out today and opened her up full throttle on the canal tow road. it's about a half-mile paved road that never has cars because there is nothing there. after about 1/4 mile i was going about 35mph. and that was where i topped out. i've got decent accel, but my top speed is still not quite where i want it.

is there something else? i'm considering rerouting the air intake to the outside, in effect creating a ram scoop. but i'm not sure if that will even do anything if i don't also fine tune the carb for all that air. gah!

maybe i should try a big bore? has anyone actually done that?

some more stuff. i cut off the end of my exhaust can. YES, there are baffles in there. they appear to be welded in there and i could not remove them. however i am gonna try cutting the can in half next. maybe do it at a 45 degree angle to get that chopper look. in any case, it added a little extra mph on the top end AND i think caused it to idle a little smoother AND it sounds pretty awesome. i will not be reattaching the cap. i'd like to reroute the air intake to the outside and i'd like unrestricted outflow.

i am still under 40mph though. maybe it's time to go on a diet!

i also removed the luggage rack, mainly because i like the streamlined look better. i also took the rear wheel off to look at how it all connects. i was thinking of attaching a bigger diameter rear wheel but i don't that's possible.

i really think that i might need to get the big bore kit if i expect to actually see a dramatic increase in power/speed.

it's a scooter. i'm not offroading in it.

Reply by carasdad on 05/08/2007 06:44:36 AM
Odd... when I posted the same info here 2 years ago... I was called crazy... it would not work...it was too easy and did not require hundreds in mods... lmao. Seems others have tried it and it works. *grin* Go figure... and.. go riding all. have fun.

Reply by jobo2mi on 07/05/2007 8:47:55 PM
I have one of these pieces of sh^&* (Panterra Freedom) that I bought from a private party (obviously no warranty OR help there!) I have ridden it MAYBE 5 miles before it just STOPPED! I have a copy of the Service Manual for all the good that does me, it may as well be written in Chinese for me to know what it says.

I have it in to a small engine repair guy, gave him the manual, and for 6 weeks he's not been able to figure out why the darn thing won't start! He cleaned out the carb (which he said had dirt in it - probably from the previous owner), he said the gas filter was in BACKWARDS! (probably from the previous owner!) and we are putting a new battery on it as the one we had didn't seem to hold a charge. It will start once or twice, he rode it all over the parking lot, but then when he shuts it off for a short time, it won't start again!! If I use it, I need to be able to DEPEND on it, what good is it if I can't zip up to the store, shut it off for 10 minutes and then start it right back up??? I am sooo frustrated with it.

I REALLY want to get this damn thing on the road -- at this point mainly so I can SELL IT and buy a more dependable scoot -- I don't know where else to turn so am grasping at straws to find SOMEONE, ANYONE who knows ANYTHING about these things. Is there something else we should be looking at ... choke works fine, Tom says compression seems to be fine, spark plug gets plenty of spark, carb is now clean, gas filter is now in correctly. Tom says it didn't appear to be turning the engine over quick enough to fire it up and start it. Hopefully new battery (which had to be special ordered - of course!!) will do the trick.

Does anyone still own/repair/ride this particular scoot?? I was so looking forward to having fun on the thing! Any advise would be much appreciated.

Reply by EdRetroMD on 08/07/2007 1:29:54 PM
Hello, I picked up one of these about a month ago 200 miles on it and it was dead... It sounds like i had the same problem your having.. Brought it home ...took the hole thing apart... Cleaned the carb. fuel filter.. and spraying starting fluid i could get the thing to run only kick start maybe every 25-30 times... I bought a battery and the thing kept dying... at one point I got the scooter to start on electric and every thing worked fine.. I turned of the scoot and it died.... I realized I had some strange thing going one.... I took everything apart and tested it.. After opening up the ignition switch I found a couple small pieces sheer off inside that shorted the switch at times and also gave a week connection to allow the key to be in the start position.

As well remember that you have to hold the right break in to start this bike... I found on the net that these scoots are know to eat the OEM ignition switch.... fast ... HOPE this helps. I will be doing some of the mods on the trans -- god this thing is slow.

Anyone know the actual size of the weights.. and what is the best weight 6mm --- 7 mmm or maybe mixing them,,,, How about a clutch spring... Looking to do this.... and wanted to know ahead of time before going to a scooter shop......

I called one shop and all they wanted was to sell me a big bore kit and said the weights would not do a thing... I will just loose top end power... they said.. Not trying to built a race rocket ship out of this death trap , just trying to get a little more speed and power for hills... Climbing a hill at 15 mph sucks.

Reply by jobo2mi on 08/07/2007 4:40:32 PM
Well I switched scooter guys and what a difference!! The new one said the carb was dirty and there was debris in the gas tank. He took it off, cleaned it out, filled it up and VOILA!! I have a scoot!!! In only two days!! (The other guy had it for over 6 weeks! )

I now ride my Panterra Freedom to work about 9 miles in town, and I can actually get up to 40 mph on the flat!! (IF the speedometer is close to accurate!) I went past one of those traffic speed signs and it FLASHED at me!! Limit was 40 and it said I was doing 41! YEE HAW!! Going downhill my speedometer says I am doing 60!! I don't know how accurate THAT is, but it FEELS like 80!!Going uphill still sucks ... bogs down to 20 or so on some of the bigger hills, but overall, I get to work just as quick on the scoot as I do in the Durango! On a LOT less fuel. When I finally filled it up, even on a conservative estimate (as I am not sure EXACTLY what the mileage was when the mechanic filled it up) I am getting about 130 MPG!! Woot!!!! Sure beats the crap outta 17 mpg for the Dodge!

Not sure if it has already been derestricted, but for right now, I am enjoying the heck outta scootin' around! What a BLAST!

Reply by PanterraPro on 09/20/2007 8:01:12 PM
NEWSFLASH!!! You don't have to buy new roller weights! Take out every other weight and BAMMMM you have the same desired effect with no purchase needed. I did this to my Retro and added 10mph instantly, not to mention the major acceleration difference. Perhaps you guys can get it better with 5 gram or 6 gram weights, but I wouldn't spend 1 dollar of my money when I saw what having three weights instead of six has done for mine. Caution: for you idiots out there-you need to remove every other weight in a symmetrical pattern because centrifugal force is hell when you have all the weight on one side of the variator. To anyone who takes my advice.. ENJOY THE POWER YOU JUST GAVE YOUR SCOOTER!

Reply by howard on 01/14/2008 7:41:40 PM
I have a baja sc50 and the motor is the same as yours a qmb139 all of the parts needed i found at scooterusa under
performance parts. I have not yet received the parts but i do know that you will need a high performance cdi rev unlimiter. I have all ready drilled out the muffler. I will post again once I have received all parts and they have been installed.

Reply by vetman1983 on 03/09/2008 12:55:23 AM
I have a baja sc 50 and was wondering what all i can do to get mine above 27. I tried removing every other weight. I then got up to 40 but now it doesn't want to go above 30 now. any ideas.
Originally posted by howard
I have a baja sc50 and the motor is the same as yours a qmb139 all of the parts needed i found at scooterusa under
performance parts. I have not yet received the parts but i do know that you will need a high performance cdi rev unlimiter. I have all ready drilled out the muffler. I will post again once I have received all parts and they have been installed.
let me know how the modifications on the sc50 work out I would like to do the same to mine if they do

Reply by Blok76 on 05/16/2008 2:13:32 PM
What happened is you ruined those 3-weights,now they cant slide like they should.When you took those 3-weights out it made the weights that you left in work harder.This will tear the weights up really fast.Just get some new lighter weights (4.5grams-6.5grams).Hope this helps and good luck!

Reply by djlucas09 on 06/23/2009 2:22:35 PM
hi everyone. just joined lol. and pranakhan, ive been reading your posts recently. their is a lot of good info their on your bikes. i have a Honda CRF70F which i picked up for £20 which i was very very happy with. it only does 40MPH top speed but i wanted to deristrict it so it goes faster. (i love speed ha ha) i read your 1st post and noticed that the deristriction steps are pretty much the same as my CRF70F. bare in mind, the bike came with NO air filter, and the end cap on the exhaust pipe (end cap) does not exist lol. i dont know if thats how its suppose to be on a trials bike or not but im not bothered lol. as long as it sounds loud, and goes fast. thats good enough for me. as for the admission, well thats going to take a bit longer as i need to find some light rollers. if anyone can find any info on my bike, it would be greatly appreciated. i need wiring diagrams, repair/owners manual free downloads. any info at all on the CRF70F. thanks all :)

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