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87 XR, XL 250R Dual carb bench set up question

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Hi, I just went through cleaning the dual carbs on my 87 XL250R. I split the carbs apart to chemically cleaned them and was able to reuse all the gaskets, jets etc. I understand the primary opens up first up to mid throttle and then the secondary starts to lift up. Can anyone tell me the position the primary slide should be in before the secondary starts to lift?. I have another carb set for reference and it seems on that one the primary moves a little higher than the reubuilt one before the secondary lifts up. I know I'll know what to do once everything is on the bike and i test ride it but I'd like to at least get it close to what it should be. Thanks in advance

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If you set it sot that both carbs are open fully at the same time, the bottom setting will be about where they designed it to be.

It is not a critical adjustment, seems to be more of a matter of personal preference as to when exactly it shoud start opening the second carb. You might get better fuel mileage if you set it so you could ride on the primary carb more.

On my 600 dual carbs, I prefer to have them both start to open nearly at the same time as is possible with the staggered linkage, I get better throttle response that way, (or so I think). True it throws them off sync at wide open, but it doesn't seem to matter much in running.

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I think the 250 is set up different from the larger bore hondas. All three of the 250 carbs that I have start the second slide when the primary slide (arch in the bottom of the slide looking at the intake side) is around half way. Even when the primary clears the top of the bore the secondary's are still showing around 25%. They both open all the way with 100% throttle position though.

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They have a bendable arm to adjust them but should ideally reach WOT simultaneously. Any other setting pretty much just defeats the point of having dual carbs. The design was intended to give better response Than a larger single carb at low speed, low throttle openings.

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I just installed my cleaned carbs on the bike as is without changing the original settings (secondary lifting when the primary half way open, the pistons lifting at the same rate and staggered until WOT) and the bike pulls great and seamlessly smooth through out the powerband. COmpared to my 81 xr200 this dual carb 250 feels like a 350cc.

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