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boring my xr to 77mm can i still use stock carb?

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my xr is stock bore now, with stock carb. was thinking bout going with a 77mm kit. due to my cylinder being alil scratched and needing a bore. can i still run the stock carb after i bore to 77mm? im plannin on getting the 34mm mikuni just cant afford it now.

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The stock carb is just fine on the 77mm piston, just spend a couple bucks on getting the right jets. No worries while you save your money.

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Thanks Red, I will do just that. You know ther is so much I wAnna do to it! I'm just wanting to get the most Bang for my bucks! In theory when you go to a larger bore dO run richer/larger jets?

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it an 86 250r, yeah ive done the simple mods, snorkle, uncorked exhaust, header welds. My current jetting is 135/45. and i seems to do good it just starting to smoke and last time i pulled it down i noticed that the cyl. wall had some sratches.

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Could your valves be the cause? If it was your rings wouldn't you be loosing compression? XRs especially old XRs tend to burn a little oil anyways. Is your smoke blue or white, constant or start up. Not to talk you out of a new bore or freshening your motor up. Just asking... If you do the bore then do your valves while its apart and vice/verse. Before you start look at other issues like cam chain. No sense opening it twice (although my tendencies are to keep doing it over and over so that I can use every expletive available :busted:)

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I hEar ya Chief, the smoke is blue. Ya I was gunna gO ahead and do the head while it's apart and cam chain. Do you recommend replAcing cam gears too?

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