XR650L Smog Block Off by Kyle

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XR650L Smog Block Off by Kyle

Post by 4Strokes » Sun Jun 19, 2016 7:43 pm

I just purchased a 2003 Honda XR650L and so begins the uncorking process. I've found lots of useful info on 4Strokes.com, but I couldn't find anything that explained exactly how to remove the smog equipment. So, I documented what I did.
  1. Remove 2 allen head screws (using a 5mm allen wrench) from both metal tubing mounts on the front of the crankcase (you must remove both mounts at the same time because the metal tubes are welded together). Don't lose the screws because you can re-use them when installing the block off plates.
  2. Remove 2 nuts from the smog pump assembly to reveal the mounting bracket bolts that are located underneath. Remove the mounting bracket bolts and the mounting bracket. Put the mounting bracket and smog pump assembly back together so you can heave the whole thing into the lake in a single motion.
  3. Remove the left-side body panel to allow more room to work. Remove the evaporation canister (the black thing that looks like a Toro sprinkler head located near the fuel shutoff petcock) by lifting the rubber mount straight up and off the mounting tab. You'll learn the fine art of "finagaling" when you perform this step. Move the spring clamps out of the way and then remove the hose(s) from each of the nipples on the evaporation canister.
  4. Pull all the rubber hoses off the plastic "T" fitting and completely remove the short hose that runs from the top of the crankcase located underneath the carburetor (its too short to be re-used). Cut the longest rubber hose that runs from the bottom of the airbox to the smog pump assembly (approximately in half) and put the open end into the botttom side of the "T" fitting. Push the hose that runs from the top of the airbox into the top side of the "T" fitting. NOTE: You'll notice that this hose is slightly smaller in diameter than the others, but it can still be pushed onto the "T" fitting. Salvage the other part of the longest hose by removing the hose clamp from the smog pump assembly. Use this chunk of hose between the fitting on the top of the crankcase and the middle part of the plastic "T" fitting.
  5. Pull the small tube off the nipple located on the back side of the smog pump assembly (approximately 1/4" in diameter). Follow this hose up to the top, left side of the carburetor. Remove this end from the nipple on the carburetor. Follow the hose further up to the "T" fitting, over and behind the carburetor to the right side. Remove this end from the nipple on the carburetor. Now that you have the entire tube removed, salvage the medium length piece of tubing from what you are holding in your hand. Route this chunk of tubing from the nipple on the right side of the carburetor up and over the front side of the carburetor to the nipple on the left side. NOTE: There's more room to run the hose in front of the carburetor. It appears that it would be more difficult to route the hose up and behind the carb again.
  6. Since I was too cheap to part with the twenty bucks for the IMS block-off kit, I fabricated my own block-off plates (to cover the open holes on the front of the crankcase). I used a flat piece of steel, approximately 1/8" thick for this purpose. First, I created a template using gasket material and an X-acto knife. Once I had the general shape, I transferred it onto the steel. With lots of sweat and sheer determination, I made the block-off plates using a hacksaw, file, grinder and heavy-duty sandpaper. You can use anything that will take metal off, if you have enough time. At this point, I began to realize the twenty bucks might have been money well spent. In any case, I made one plate and then used it as the template for the second plate (just reverse it for the other side). I secured the plates using the same allen head screws that were removed first. NOTE: I didn't use a gasket underneath the block-off plate but I'm considering doing that to prevent leakage.
Credits: Article written and submitted by Kyle Swanson. Edited and published by 4Strokes.com.

Posts: 17
Joined: Oct 25, 2016
Location: Reno Nevada
Rides: XR650L
Vehicles: Jeep Wrangler, RAM 1500

Re: XR650L Smog Block Off by Kyle

Post by Plud » Tue Oct 25, 2016 7:12 pm

Consider perhaps just cutting down the factory plates, flatten and weld the metal hose closed? Plug with JB weld? Lots of somewhat 'hacky' options that don't require fabricating new plates.

Posts: 78
Joined: Jun 10, 2016

Re: XR650L Smog Block Off by Kyle

Post by JoeRC51 » Wed Oct 26, 2016 5:50 pm

I cut mine out of 3/16 aluminum.

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