After carb rebuilt poor low end performance

Joined
Apr 15, 2012
Messages
4
Location
Hickory,nc
I let my 91-st1100 sit for over a year and sure enough it jets were plugged. I read all the suggestions and instructions from this forum and proceeded with removing the carbs. Very good instructions by the way. I replaced the jets (#40, #128), the carb boots, inspected the diaphragms. The float level seemed to be ok at around 3/8th? The jet kit came with spacers but I did not use them. I removed the PAIR, Fuel shut off vacuum switch, and by-passed the evac canister. Plugs look good and I poured seafoam directly in the carbs and in the gas. I have ran a tank of gas. The motor runs strong and pulls harder on top end but is lousily on low end. It starts and idles well but from 2k to 3k it flutters.
What can I do?
 
If it is 'fluttering' at low rpms I'd be looking for clogged jets.
However; you changed the jets. Did you replaced them with the same size?
 
You mention changing the jets but did you boil the carbs? If not some of what clogged the jets in the first place may have been left in a passage and clogged the new ones.
 
Pilot screws set properly???????????????????

If one doesn't remove them and carb cleaner gets on the o-rings, it can deteriate the rubber o-rings and clog the pilot circuit.
 
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Boil the carbs? Maybe that's what I need. I recently synched my cards with the sk flowmeter and got em all the same. But it runs sort of rough at low rpms. I did remove the jets and cleaned those. Maybe there was some junk inside the carbs that fouled them back up. Is there such a thing as boiling the carbs? If so what what has to be removed to ensure nothing inside is damaged.
 
I figured out the problem-one of my floats was significantly out of spec. I reset it to .280". I also reset the pilot screw to 2-1/4 turns after purchasing the $80 tool. My ST runs great.

Thanks
 
You don't want to know! Remover everything to boil the carb.
Ron

Um,...I think he does.
Popo ive been doin a lot of reading as Im planning on doin a re-build.I bought this book by Mike Nixon,http://www.motorcycleproject.com/motorcycle/text/booknook.html#12 ,which I highly recommend.He will also answer any questions you may have after reading it,as Ive had a few myself.
Basically he recommends fully disassembling the carbs,cleaning via chem bath or ultra sonic,replace all o-rings and jets(if necessary)doesn't look that hard,just have to be careful keeping everything organized and sorted pics and notes help.Honda does have a OEM part # for replacing all float gaskets and o-rings for about $25 bucks.I ordered those, if Billy C comes up with a complete kit I'll offer the Honda kit up to the forum for cheap.Im not at home but when I get back tomorrow I'll post more info.
 
Plugs look good and I poured seafoam directly in the carbs and in the gas. I have ran a tank of gas.

I have heard that pouring seafoam directly onto the o-rings can degrade them. Anyone else hear that?
 
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