Tech Tips: Throttle Body/Carburetor Removal

Swapping out an engine, or giving a bike a full race prep? Need to get that pesky throttle body or carburetor out of the way? Click play for some tips and a how-to on removing it.

Looking for motorcycle parts, accessories, or gear needs, you can find them at Chaparral-Racing.com.

Transcribed version:

"Hey, this is Mike Lindsay from Vital MX. and we're here at Chaparral Motorsports today. Whether you are in the new era of fuel injection or your bike still has a carburetor, it's definitely useful to know how to dive in and take it off. So today, we're going to show you how. Now, we're going to get down to the throttle body and/or carburetor, which is a little bit deeper in the bike. So we're going to have to remove most of the back half of the motorcycle. For that, we usually do this with an 8, 10, 12, 14, and even 17-millimeter end wrenches or T-handles, along with some needle nose pliers and a couple Allen wrenches should get the job done. 

So the first step we need to do is to remove our seat. So we're getting our seat bolts out, and remove the seat. Before we can remove the subframe, we need to jump in, take the side plate off, and remove the exhaust. For the most part, the tank strap needs to be removed to either get this cover out of the way, or sometimes the tank strap is actually hooked to the subframe. With fuel-injected bikes, we need to unclip the air temperature sensor. Now, finally, to actually get the subframe off, we're going to remove the bolts holding it in, usually between three and four bolts, top and bottom. Ten to twelve-millimeter tools can remove these. So the last thing holding the subframe in place is actually the air boot connection to your throttle body or carburetor, which is always held on by a clamp here. It's either an Allen or typically a Phillips head bolt you just have to loosen, until the clamp is nice and loose and can rotate, so you can pull the air boot off the injection unit. Sometimes you can simply just pull on your subframe, and the air boot will remove itself. Other times, though, you may have to get a flat blade screwdriver or something to help you pry the air boot free from the throttle body. 

Okay. So to get a little more room here to work with our throttle body, you can either remove the shock completely or you can just remove the top mount and lean it back. The next best step is to get this throttle body to the point we can move it around and work on it easier. So we're going to loosen the front clamp that connects your throttle body or carburetor to the actual cylinder head or cylinder. We can just go ahead and get this loose enough. We got our throttle body loose enough now, we can rotate it and access all the further pieces we need to remove to get it out. So whether dealing with carburation or fuel injection, we usually have a cover here that's protecting the reels for the throttle cables. Typically, there is one, maybe even two Allen bolts holding these covers on. You just want to remove those. So we can remove the cover and expose the reels. Now, to free our throttle cables from the reel, we need to get a little extra slack to work with. So we have to loosen the locknuts here to get the ends of the throttle cable out of the actual body itself. If you're dealing with a four-stroke, there are two of these. Two stroke, you only have one cable. You just want to break... I've kind of broken these loose anyways, but get them loose, so you can reach in and just pop these out. So you can get all the slack you need to work with. 

We can either get these out with our fingers, or if you have a set of needle nose pliers, it can definitely make life easier. When we move over to fuel injection, though, we have to deal with these pressurized fuel cables we need unclipped, and we have a few more extra electrical connectors that need to be pulled off before we can remove the throttle body from the chassis. Now that all of our electrical connectors are unplugged, we need to get the fuel line off. Most of them are some kind of clip that you'll want to pry with your finger on each tab or get a screwdriver under. They typically hold the fuel line on a ridge in here. You want to be careful...some of these, like the one we're dealing with here on the Suzuki, is pretty simple to unclip. There are some brands that are pretty stiff, and if you pry on them too hard with a screwdriver, you'll break the tabs and they are not easy to get replacements for. You have to end up getting a whole fuel line tip. Once that's removed, our throttle body is out. Now that we have our throttle body and/or carburetor out of the bike, it's a great chance to inspect the unit and clean it before placing it back in the bike. When putting it back in, just repeat all the steps we've shown you. 

The two biggest to watch for if it is a fuel injection unit, to make sure all the electrical clips are completely seated. Or otherwise, when you go to start the bike, you may have a few problems. Also, to make sure the clamps on both the air boot and the cylinder end are tight, so everything is sealed up. Other than that, the subframe bolts, make sure everything is back where it belongs. Then, as for cleaning, check out some future Tech Tips, as we'll show you how to clean the injector unit, and how to tear down and clean a carburetor. "

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