XR650L Smog Pump Removal

I would like to remove the smog pump from my 2004 XR650L. Is this possible without installing a aftermarket pipe and rejetting?

I would like to remove the smog pump from my 2004 XR650L. Is this possible without installing a aftermarket pipe and rejetting?

Yes, the smog pump does not affect the jetting.

The bike is jetted quite lean stock, though.


You dont have to pipe and jet but I would really recommend it.

IMS makes a kit to block off the ports on front of the cylinder and comes with great instructions on how to do this as well as plugs for the vacuum ports. You don't necessarily need the kit if you have a way of making the block off plates. But if you don't want to fool with it, the kit works great. I got mine through Baja Designs. Not sure who else my carry it. As Dave said, the stock carb settings are pretty lean and you'd probably be happier by richening up the main and the slow jets.

There is no noticeable gain in power from this mod. It was the first thing I did when getting my bike bone stock with 600mi on it. Just seemed to pop a little less maybe on deceleration. A good pipe, the proper jetting and drilling slide and uni filter will open up your beast quite a bit, and changing gears really help close the 1-2 gap and climb hills like a mutha.

So is there any performance reason to remove the smog crap or is it simply aesthetics and a couple of pounds weight loss?

It does lessen the pop on deceleration and, yes, it does look better and saves a few pounds. Personally, I think it makes it easier to work on the carb with the fewer hoses to deal with; not to mention less chance of a vacuum leak. I still don't see where the 650L could possibly cause enough pollution to warrant the damn thing to begin with. If you don't need it, why have it?

Again, just my opinion and you know what they say about opinions ...

Thanks for all the info! Looks like I'll start with the block off kit from Baja designs. I guess the next obvious question is what aftermarket pipe would be best suited for my 650L? I commute some of the time with the bike and leave at 4am to get to work so I need something that won't cause my neighbours to much grief. Thanks for the help!

The White Bros E2 works great but is noticeably louder, especially if you running hard on the gas (WFO). This is the only one I've had experience with. You will need to re-jet if you install this pipe and not sure what your neighbors will be real happy when you fire up at 4 am. My neighbor has the same pipe and pulled the spark arrestor just to see what it would sound like. Believe me; if it would have been 4 am, you probably would have read about a motorcyclist's murder in southeast Texas. If you get one, leave the spark arrestor in.

There's another string going, possibly in the general forum, about how aftermarket pipes aren't worth the money - strong opinions pro and con.

i purchased a smog block off kit from al bakers xr's only 2 plates and vacuum plugs and your good to go.

as for a muffler i have the fmf Q series pipe it is quiet i had it tested at a dualsport ride here in cali and it was at 94 decibles also it is us forest approved

i also opend up the air box, re jetted and drilled the slide,these mods really woke the pig up anyway i hope this helps you :ride:

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