RaceCar1983
XS650 Enthusiast
First post ever so here it goes, my 72 xs650 chopper with a freshly rebuilt top end and all new electronics struggles to idle when started and backfires out of both carbs, if it does manage to keep started long enough to rev, it bogs down when given throttle. I did a compression test and read around 110 which is low, but I need to confirm with a gauge I trust. So far I have redone timing/valves, replaced both points, and replaced advance springs that were barely snapping back with no change.
I also should mention I made sure the carbs are PRISTINE, checking all the jets and clearing them. Different jet sizes and mixture adjust make no difference so I can only assume my problem lies with my advance/timing/valves. Any ideas or order of rechecking my work I should follow? Running stock points with xs charge PMA if that helps. Thanks for any ideas.
Edit: bike ran fine 200 miles after rebuild until this happed FYI so the rebuild is unlikely to be the problem
I also should mention I made sure the carbs are PRISTINE, checking all the jets and clearing them. Different jet sizes and mixture adjust make no difference so I can only assume my problem lies with my advance/timing/valves. Any ideas or order of rechecking my work I should follow? Running stock points with xs charge PMA if that helps. Thanks for any ideas.
Edit: bike ran fine 200 miles after rebuild until this happed FYI so the rebuild is unlikely to be the problem
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