White Brothers XCR and jetting?

I just installed a WB xcr on my '06 250x and the instructions stated I could use the stock jetting, but that sounded wrong. I figured Im making a lean engine even leaner with the pipe, so I changed the jetting to 42p and 135 main. I also cut the top of the airbox, but no other mods. On start up, I didnt have to use the choke and noticed the idle was a little high after a 5 min ride. Any suggestions? Should i just adjust the idle speed and call it a day? Thanks in advance.

I would step up the main. The 42 pj should be fine. I was running somewhere in the 150 range with a full CCC mod to the airbox and just the XCR muffler. Have you considered the JD kit (Cycle Gear stocks them)? You get his needle and a variety of main jets plus orings that modify the AP to give better throttle response. Changing the leak gave me great throttle response as well.

Id jump up to a 155 because youre still dangerously lean

It sounds like the other responders have you pointed in the right directions but also check out my post from yesterday on Hanging Idles just in case. There is some good infor on the TPS in there. It never hurts to be informed.

Best of luck.

I'd be going to a 162 main at sea level. How loud is the muffler?? does it have a db reading??

It's pretty loud in comparison to the stock muffler, but no db rating....thanks for the info guys it's greatly appreciated.

I'd be going to a 162 main at sea level. How loud is the muffler?? does it have a db reading??

97.5db is what mine checked at. That is with an open airbox (full ccc cut) so if your airbox is not opened up as much it may meet the advertised 96db rating.

Im not sure what a "full ccc cut" is? I just removed the top lid of the airbox and dremeled out the two original holes about 3" x 1". Should I have done something else?

Im not sure what a "full ccc cut" is? I just removed the top lid of the airbox and dremeled out the two original holes about 3" x 1". Should I have done something else?

It essentially turns it into an R airbox. There is a large line in the stock airbox for you to cut to follow the "closed course competition" modifications. IMO I would not do the full cut. I believe it lets in way too much dust when compared to the stock opening and contributes to the noise factor. I would just cut a slot in the top and call it good.

It essentially turns it into an R airbox. There is a large line in the stock airbox for you to cut to follow the "closed course competition" modifications. IMO I would not do the full cut. I believe it lets in way too much dust when compared to the stock opening and contributes to the noise factor. I would just cut a slot in the top and call it good.

Hey jfgjr I was wondering how it contributes to the noise issue since it is before the cylinder. Im not trying to be an ass, Im just curious:thumbsup:

Hey jfgjr I was wondering how it contributes to the noise issue since it is before the cylinder. Im not trying to be an ass, Im just curious:thumbsup:

No offense taken. I gathered the info from some muffler tests that the one of the mags had (Dirtrider or Dirtbike). They had a huge pipe shootout for the X and they said that the intake noise contrbuted to a higher db reading during the sound checks. The intake noise is quite significant with an open airbox.

Hmm thats interesting. I never would have guessed that it would affect the exhaust volume

Hmm thats interesting. I never would have guessed that it would affect the exhaust volume

Dude whatever you do don't listen to anything I have to say and give it any serious thought:lol: I may have selective memory. Perhaps I am just looking for an excuse not to be POed that my exhaust did not meet the 96db rating as advertised:excuseme:

what size exhaust tip do you have in and do you have a sparky.

what size exhaust tip do you have in and do you have a sparky.

The sparky and the 96db insert are in the muffler. I mean it only tested at 97.5db not llike a 100 or anything. I am just old, grouchy,and like quiet bikes. I just wanted more power and the lighter weight of an aftermarket silencer. I like the way the WB E2 sounds as it is quite a bit more quiet than this pipe. I just was looking for a bargain.

I know what you mean jfgjr. I would like companies to make a pipe that makes great power and is below that 96 db limit but theres not a huge market for it. Im saving now for a suspension job then going to get a Mr. D because of his quality service some of my buds have gotten

I know what you mean jfgjr. I would like companies to make a pipe that makes great power and is below that 96 db limit but theres not a huge market for it. Im saving now for a suspension job then going to get a Mr. D because of his quality service some of my buds have gotten

Good call. More than one of my buddies have MRD pipes and they love them and rave about the customer service. I think the FMF Q tested quite low and I know a bunch of guys that have the WB E2 and it real quiet too.

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