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Tuning the twin carb on an 85 XL/XR350?

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Does anyone have any experience with tuning the dual carb setup on an 80's ish XR/XL350? I have just about given up. The bike in question is an 85 XL350R that was originally a California edition. I restored the bike and removed all the emissions garbage and am finally done with it except one little issue. With stock jetting, it chatters and sputters like it is running too lean. So I went up in the main jet and secondary jet several sizes. Now it starts, idles and runs perfectly until just past quarter throttle (presumably when the second carb is coming on), then it hesitates almost like a bog then takes off. I am thinking it is the timing of the secondary carb. My experience says it is bogging too rich due to the fact that it no longer sputters. Any suggestions would be MUCH appreciated!

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If the bikes stock (ie Airfilter/Muffler) then it should run ok with the stock jetting. I suppose you could try making both carbs open at the same time. The mechanic who re-co'd the carbs on one of my twin carb 600's set them like that and while I can't say I notice a difference in any way from the normal setup it may be worth a shot..

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I've had the same problem on a twin carb XR250 and the fix was removing the carbs and doing a very throrough cleaning. The easiest way to remove the carbs is to remove the manifold from the left side with the carbs attached.

Carb cleaning

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Hey mallard75 I've got the same bike except not california. My manual says that the second carb is only for high end so I don't think you should be tuning them the same. If you need more specifics let me know and I can check my manual. goodluck

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What emnem said, the second carb is only to kick in for the upper range.

You should ask the "jetting section" forum, that guy is a whiz.

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