Another XR650L jetting question.....

Hello all... This is my first post, but I'd like you all to know I've already learned a lot about my machine from your past discussions using the search feature.

I just purchased a 2000 XR650L with a White Bros. E-Series pipe. The previous owner said the local Honda shop had re-jetted it for him, but it was obviously burning way too rich. I checked the air filter, it was the stock filter and totally plugged up. I got it home and removed the smog pump to get rid of the popping, ripped the snorkel off the air box, and opened up the carb to check what jetting I had. I have a 152 main, 55 pilot, and it appears to be a stock needle (J8KC).

Now for my questions: I will be ordering an Uni foam filter and riding between 800' and 3500' elevation. What main jet should I pick up 160 or 165? There is a plastic stepped washer under the needle now, is this stock or somebodys attempt at shimming the needle? Do I add a .035"-.040" washer in addition to the plastic washer? I will also be drilling the slide out to 5/32". The WB pipe is too loud for me, will the WB silencer add on tip help much?



P.S. Almost forgot, I'll be grinding the tab off the bowl to be able to adjust the air screw. Where should it be set? It was at 2 1/2 turns out.

With the pipe, I would go for the 165 setup. I run the Dynojet needle but I hear the stock one shimmed to .035 works better. I am running the 52/160 setup in mine which is right on for my elevation but I still have the stock pipe too. I'm not sure about the WB tip, hopefully someone else can answer that one. I drilled my slide 5/32 also but didn't notice a whole lot of difference. I think it's the Dynojet needle. I wish I could get my hands on a stock one to try it. Good Luck.

uw153, When you replaced your needle, did the stock needle have a plastic washer under it? I'm not talking about the plastic needle retainer, mine had about a 1/8" thick plastic washer to raise the needle up. The dealer didn't show one in the parts catalog. I think the previous owner was attempting to shim the needle, but just went too thick, thus making it too rich.


When I bought mine, the jet kit was already installed 50/160 with snorkel still attached. If the plastic bushing doesn't come in the microfishe picture I would say he added it. If he added it and it's truly 1/8", WOW, I think that would be rich as hell. I wish I still had the stock parts so I could tell you. Does your needle have a removable clip or is is pressed on? Can anyone who has changed their stock needle position help this fella out??

My needle is the stock one without the adjustable clip. I got anxious this evening and had to try it out. The largest jet I could find locally was a 160. I took out the plastic washer and installed a .035" shim, drilled the slide 5/32", I don't have an UNI filter yet, so i just left the stock plugged up filter out and took it for a quick test ride. At first it was hesitating terribly but as it got up to temp. it smoothed out and WOW what a boost. If you take off in first and quickly crack the throttle wide open it will pull the front tire up without a problem. Before it wouldn't come close. Too early to tell if the 160 is going to be O.K. or not, I really need to get my air filter before I do much more with it.

Thanks again,


Sweet, that's about how mine runs. Mine hesitates a little when it's cold also, I think I can get away with a 55 slow jet also but I think I'll try the 52 for awhile. Mine will rip the front end of the ground easily in first and bump in second. "warm'd up of course" I can't wait to get a pipe and increase the main even more. I just bought the IMS 4 gallon tank to I have to wait a bit more now. (I'm a cheap a$$)

That's going to be my next investment, a larger tank. I've been looking at the different ones; IMS, Clarke, and Acerbis. Why did you choose the IMS? Are there any pros or cons between them?

Wpoling I had a 98 xr650l, sold it to get my xr650r. Mine had a vapor control charcoal cannister on it not a smog pump. Was it on the left side of the engine on a bracket connected to the motor mount? You seem on top of the jetting to me. I installed the dyno jet kit, uni air filter,and fmf mega max. Performance improved but it was LOUD and on decelaration it made snap crackle pop noises I disliked. I wondered if that was the popping noise you described. I think the WB insert for the stock exhaust is the way to go. Inexpensive, good performance and quiet. Im not sure if you have the stock exhaust or were referring to the core insert for the WB E series. The friend I sold it to replaced the cv carb with a Mikuni and it impressed me when he let me ride it. The Baja Designs web site has good information too. Congrats on the new bike!

From what I have read, the IMS seems to have the fewest problems in installation. And it's the only one I found in red. The larger Acerbis would be nice but I didn't like the look of so much tank. I read the Clark had some discoloration and installation issues. So I decided on the IMS. The Acerbis is cheaper though. All I had to do was increase my range to greater than those I ride with. At 75 miles with the stock tank, I couldn't do that.

I got an IMS 4.6 for my 650r (baja designs) and it fits so bad it's rubbing in two places (engine and shock res) and it's has a permanent indentation (factory flaw). Yea, I should have sent it back, but I tried to make it work. So I'm thinking about getting the Clark 4.3. People here have said they like the fit an finish of it. I definetly won't buy it from Baja Designs- I feel they should have warned me of the poor quality in the first place. Not sure if the issues are the same for the 650L.. Anybody want my IMS for cheap? It still works, maybe you can use it as a second tank. :)

Got the IMS today, installed it, filled it, and rode it. Not bad, not perfect. No real flaws, very easy installation though. I just wish they hid the parting line a little better, but sometimes you just have to make due. All in all, I'm still happy with the money spent so far. If I have issues, I'll be sure to post.

Nobody ever responded to my question of there being a plastic washer under the needle of their XR650L. Any takers?


Don't need no stinking new jets, just drill the old ones. Been drilling them for years with excellant results.My 00 XR650L has the muffler baffle, airbox snorkle and all the smog plumbing removed,and a homade two stage foam airfilter(future post).The idle jet is drilled with a #76(.020") drill, the main jet is drilled with a #53(.059") drill, the needle is shimmed up with two washers, .040"+.020" for a total of .065"up. The sparkplug color is textbook perfect in FL. the drill sets are available at any mill supply(try for the #60 to #80 set.

The plastic washer you found under the needle is bogus, throw it away!

When the idle jet is correct the fuelscrew will "tune" the idle, too far out, the idle speed slows down, too far in, the idle speed slows down also. Mine is aprox. 2 1/2 turns out. Remove the top from the fuel screw, solder a 1/2" piece of bicycle spoke (preferably S.S.) and make a nice "T" handle you can turn with your fingers. Procede with care and caution and your bike will run like a train (a fast one!).

Let the flames begin about how jets are precision honed and drilling is too crude to work, I can take the heat!

I have a 97 with stock carb and I'm actually cleaning it out right now and I don't have a plastic washer under the needle. Don't know if I would use HotWheels technique of drilling out the jets though. Seems too much trouble for a $2.00 jet. And also I understand that they are measured with fuid flow, not opening size. Matter of fact I cleaned my carbs on my gsxr and 2 jets, both 137.5 had visibly different size openings. Almost like one was 128. Anyways it seems to work for him so maybe I'm just lazy...

Never drilled bike jets, but i have drilled the jets in my sandrail when i couldnt find the right ones. Works great, just some trial and error.


Don't drill anything that's the old way the kits came up towards the beginning of 2003. After that BD's shipped a new jet kit that comes with everything. I'm on the east coast so my altitude might be different from you. I notice alot of the guys with the older bikes will suggest this and that but take my advice for anyone who want to rejet their "R" or "L" as my buddie and I both did it to our 2003 models. Call the 1-800 number at Baja Designs and talk to the guys they will tell you everyhting you need or want to konw. That's what we did, get your kit, follow the instructions and you will notice the performance increase. And if these a problem, which there won't be, you can always "UNDO" the installation of the new kit and go back to factory or previous setup. It's that simple, don't mess around call and get the very latest info and the proper jetting kit for your bike.



[/ Just Got A 1993 Xr650l For $50it Has A Fmf T4 And A Uni Filter.. I Think I May Be Having Some Of The Problems You Are Talking About. It Falls On Its Face On The Low End And Pops When I Back Off The Throttle. Its Clean Bike And I Realy Like The Big Thumpers. I Also Have A Drz400 With The Dyno Jet Kit And A Qwick Shot, The Dyno Kit Worked Great On Tha Bike

[/ Just Got A 1993 Xr650l For $50it Has A Fmf T4 And A Uni Filter.. I Think I May Be Having Some Of The Problems You Are Talking About. It Falls On Its Face On The Low End And Pops When I Back Off The Throttle. Its Clean Bike And I Realy Like The Big Thumpers. I Also Have A Drz400 With The Dyno Jet Kit And A Qwick Shot, The Dyno Kit Worked Great On Tha Bike

Welcome to TT Don!

Sounds like you need to check on the jets in your carb and rejet. 158/55 is a good start with doing "Daves mods" a quick search will reveal the info needed.

Plus, what exhaust do you have and any intake mods(foam air filter, snorkel removed)?

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