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Briggs Flathead / 18 hp apposing twin runns bad
« on: March 31, 2009, 05:02:58 pm »
need some advice from anyone that has any ideas im new to these motors i have a stock 18 hp flat head apposing twin with new coil but stumbles bad off idle and surges at full throttle i tried adjusting enrichment screw but doesnt help it is a gravity feed set up no pump it does have a custom built header that is two into one straight pipe. it also backfires alot i do know that on our kart motors the single cylinder flat heads thats normal but dont know if normal on this motor any help would be greatly appreciated