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thebigblue · 07-03-2011, 02:27 PM

bought over a month ago from a guy who left it sitting for 3 years. when i bought it we drained crud out of bowls and tank. added some fuel, changed the oil and plugs. started, idled rev'd fine. ran alright except for half throttle backfire and decel backfire. brought it home and waited for my MSF course. Passed course and just reg'd bike. over the past month i'd go out and start bike every few days, let it warm up until fan kicked on and then rev it a few times. didnt dare ride it until i had endorsement. anyway, last week i pulled carbs for a quick go over. pulled bowls and found heavy grass-green mush all over the place. scrubbed it out with nylon brush and carb cleaner spray. soaked bowl gasket in wd40 because it was flat and fairly dry. pulled jets and needles, they had some heavy varnish and crust on them. cleaned with nylon brush, some steel bristles and fishing line. blew out all passages. one of the idle mixture screws stripped so i had to get creative. drilled out center of screw head. tried the cheap hex head trick mention ed on this forum. of course it snapped off. stupid idea. should have tried the more expensive ez out method first. removed most of bare hole with a dremel disk, drilled out the snapped hex head and drillde hole deeper for ez out. worked like a charm. though i was in trouble because i dremel'd some of the mixture screw threads. turns out i had just enough left to get 2.75 turns out of screw before a leak would develop. took it down to my local harley-type shop to match up some new bowl gaskets and a new mixture screw. the owner benched the carb, tore it apart, replaced all the brass set the mix screws and sealed the damage(cept for the phillips slots of course) with some flexible black stuff. he tore out the bored out dynojet jets and double tapered needle and replaced them with stock diaphragm needle and oem jets 2 sizes larger. running 45's or 48's and 175's. left bowls alone. he put some fuel proof sealant on bowls and sent me on my way for a total price of (hold onto your seat) $20!! awesome. 3 week wait my butt, i was in and out in 40 minutes. put it back on bike. let fuel flow a minute. cranked about 7 seconds and it fired up and idled perfectly. choke on for about 20 secs. i got nervous because it would miss or backfire at half throttle and higher. turned ratio screws in about a 1/4 turn for something like 2-2 1/4 out. still did it. i was disappointed and thought i might have been better off with the modified dynojet stuff. i decided to take it around the block a few times before pulling carb again. i was impressed. zero backfires, huge torque especially kicking in around 2500rpm , zero hesitation. has unbaffled drag pipes and a k&N. no idea on timing advance. what do you all think? leave it alone or cure the half throttle backfire (on kickstand)? i used 3 gallons of 91 octane and added 1/3rd-1/2 bottle of berryman B12 to clean valves and combustion chamber. put 2.5 gallons in tank. could the high dose of b12 cause backfire issue?

07-03-2011, 02:27 PM	#1 (permalink)
thebigblue Junior Member Join Date: May 2011 Location: NW Florida Posts: 8	1996 1100c2 ace first ride. a saga. bought over a month ago from a guy who left it sitting for 3 years. when i bought it we drained crud out of bowls and tank. added some fuel, changed the oil and plugs. started, idled rev'd fine. ran alright except for half throttle backfire and decel backfire. brought it home and waited for my MSF course. Passed course and just reg'd bike. over the past month i'd go out and start bike every few days, let it warm up until fan kicked on and then rev it a few times. didnt dare ride it until i had endorsement. anyway, last week i pulled carbs for a quick go over. pulled bowls and found heavy grass-green mush all over the place. scrubbed it out with nylon brush and carb cleaner spray. soaked bowl gasket in wd40 because it was flat and fairly dry. pulled jets and needles, they had some heavy varnish and crust on them. cleaned with nylon brush, some steel bristles and fishing line. blew out all passages. one of the idle mixture screws stripped so i had to get creative. drilled out center of screw head. tried the cheap hex head trick mention ed on this forum. of course it snapped off. stupid idea. should have tried the more expensive ez out method first. removed most of bare hole with a dremel disk, drilled out the snapped hex head and drillde hole deeper for ez out. worked like a charm. though i was in trouble because i dremel'd some of the mixture screw threads. turns out i had just enough left to get 2.75 turns out of screw before a leak would develop. took it down to my local harley-type shop to match up some new bowl gaskets and a new mixture screw. the owner benched the carb, tore it apart, replaced all the brass set the mix screws and sealed the damage(cept for the phillips slots of course) with some flexible black stuff. he tore out the bored out dynojet jets and double tapered needle and replaced them with stock diaphragm needle and oem jets 2 sizes larger. running 45's or 48's and 175's. left bowls alone. he put some fuel proof sealant on bowls and sent me on my way for a total price of (hold onto your seat) $20!! awesome. 3 week wait my butt, i was in and out in 40 minutes. put it back on bike. let fuel flow a minute. cranked about 7 seconds and it fired up and idled perfectly. choke on for about 20 secs. i got nervous because it would miss or backfire at half throttle and higher. turned ratio screws in about a 1/4 turn for something like 2-2 1/4 out. still did it. i was disappointed and thought i might have been better off with the modified dynojet stuff. i decided to take it around the block a few times before pulling carb again. i was impressed. zero backfires, huge torque especially kicking in around 2500rpm , zero hesitation. has unbaffled drag pipes and a k&N. no idea on timing advance. what do you all think? leave it alone or cure the half throttle backfire (on kickstand)? i used 3 gallons of 91 octane and added 1/3rd-1/2 bottle of berryman B12 to clean valves and combustion chamber. put 2.5 gallons in tank. could the high dose of b12 cause backfire issue? Last edited by thebigblue; 07-03-2011 at 02:33 PM.