bike was not running well at all. someone suggested re-dipping the carbs. did that and replaced all the o-rings. benched synced, but i noticed that #4 wasent closing all the way like the rest, but was just at the foremost bypass so i dident worry about it. tried to sync them up at about 2000rpm i can get them close but as im adjusting #4 its all the way out and i cant get it to go any higher. all i can think of is to bring the rest in to compensate. its ether that or replace the butterfly or spring on #4?? or an i just completely? mad
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refeicul
well well well.... sigh
bike was not running well at all. someone suggested re-dipping the carbs. did that and replaced all the o-rings. benched synced, but i noticed that #4 wasent closing all the way like the rest, but was just at the foremost bypass so i dident worry about it. tried to sync them up at about 2000rpm i can get them close but as im adjusting #4 its all the way out and i cant get it to go any higher. all i can think of is to bring the rest in to compensate. its ether that or replace the butterfly or spring on #4?? or an i just completely? mad
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refeicul
i also saw the #'s on the butterfly's were different. on the originals they say 130 and the replacement carbs are 135 anyone know what that is? i dident see and thing on it in the manual or the carb spec sheet
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Flyboy
Just a thought, but how are your butterfly shaft bearings, is there not perhaps an air leak there?
I am just trying to get my head around the constantly changing vac.
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refeicul
ya i dunno... im at wits end and starting to think about giving up and just getting a newer more reliable bike.
idle is all over the place after the carb rebuild like b4, and stalls out unexpectedly
the only things left is new plugs, timing or rechecking the valves
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refeicul
Originally posted by Flyboy View PostJust a thought, but how are your butterfly shaft bearings, is there not perhaps an air leak there?
I am just trying to get my head around the constantly changing vac.
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Originally posted by refeicul View Postthe other tip i could think of is dont half ass stuff or take short cuts!Regards,
Andy
Queensland Australia
http://i117.photobucket.com/albums/o...h_PIC00011.jpg
GS750B (1977)
Wiseco 850 kit, K&N pods, 4-1 transac, Custom 2 pak paint, IKON shocks, Custom L.E.D light boards (turn + stop/tail + dash)
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refeicul
well this is odd well i pulled the crashbar and sig gen cover and just tried to staticly see my timing with out a light.. i cant find the fire mark for 2-3 i see the numbers 2-3 then after that, T then im back to 1-4... i see the fire mark for 1-4 just like in the manual i see the T... am i crazy? ill have pictures in a bit
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refeicul
all righty then well nevermind... ok the o-rings on the intake are 1yr old... timing looks good all thats left is the tappets.. after that im at a loss
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Jason the terminator
I don't know if this is possible on motorcycle carbs but on a car carb you can over tighten the screws that hold the body together. This can cause air leaks and tuning would be almost impossible. Another thing is the ambient air temp. is it about the same as the other days you were trying to tune?
Some good info I found might be able to help you.
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refeicul
as of late its been 40-50 degrees for the past 4 weeks during the day when i i have been working on it.
after the rebuild when i fire it up with full choke it revs to 3000+ the carbs are 2 turns out. on the up side it fires somewhat easily but ya thats way higher than b4 it was about 2000ish
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I would try re-adjusting the idle using the highest RPM method again. I've found that minor adjustments to those mix screws make big differences in how the bike starts, idles & takes off.
Two turns out sounds a bit lean to me - warm the bike up, adjust the idle to around 1200, put a fan in front on it & systematically adjust each mixture screw until the engine RPM is at it's highest. You kinda have to listen & "feel" the bike vibration as you do it.
Blip the throttle & see if it's getting smoother, reset the idle back to 1200 and move the the next carb. I do the inside ones first (2 & 3).
When done right you should hear the exhaust go from a kinda "tinny" sound, to more of a lower rumble (relatively speaking). Also, when you blip the throttle it shouldn't bog or hang at the higher RPM's.
THEN do your carb sync & see if it's better... might want to raise the needles too, to eliminate any mid-range flat spot.
good luck'85 GS550L - SOLD
'85 GS550E - SOLD
'82 GS650GL - SOLD
'81 GS750L - SOLD
'82 GS850GL - trusty steed
'80 GS1100L - son's project bike
'82 GS1100G - SOLD
'81 GS1100E - Big Red (daily rider)
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refeicul
thanks guys jumping back into the garage today..
tried starting it a min ago and noticed carb 1 was jiggling back and forth. was able to tighten the clamp almost half a turn. checked all of them and it fired up smoothly and idled better than it has in awhile. im gonna try and re sync if it stays consistent ill be happy. and ill reset the mix screws while im at it
thanks i feel like an ass.
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refeicul
idles well
sync wasn't far off
now if i had afew $ for gas
also tried to do the high rpm method and ya with the idle screw all the way out and there was no end to the rpm's... in order for me to use the idle screw i had to turn in the mix. but no popping! the pipes sound even and throttle response is noice
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refeicul
ohhhh YEAH
Well ya all know i couldent resist a test drive my usual 20 mile trip. all i can say is holy undergarments batman!!! Climbing hills in 5th again.. slid out the back tire once cause the guy in front of me broke suddenly but it was awesome to take a ride without going "why does it sound like this? Or what was that?" or a few 4 letter words Not quite smooth as silk but defiantly Jersey knit. Cant wait for monday its going to be in the mid 70's yay no layers
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