Bike jerking issues CARB?...

58flh
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Re: Bike jerking issues CARB?...

#31

Post by 58flh »

ItsRich!-----I wouid lower the gear ratio! & start out the Idle at a 1000Rpm,-That should be more then enuff for that BH-Cam!---As far as working the clitch--What you will actually doing is HEATING it up!,Cause your letting it slip --pull on lever ,disengages clutch,& rapping the throttle is causing it to slip!--& that's ALOT OF HEAT!.--Your steels will warp & purple on you,,NOW you have a Clutch problem!---Lower your gear ratio!-(it will surprise you how nuch a differenece it makes!).You should olny pull the clutch in when your ready to take a shift!,-Or while downshifting to slow-up the bike!--But Rideing the Clutch is not a good Idea,It affects the throw-bering & Makes ALOT OF HEAT when your making them plates slip against eacother!---Respectfuly---RICHIE
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Re: Bike jerking issues CARB?...

#32

Post by itsRICH »

Yea, I didnt think about that, thanks for the input, will be looking into the gear ratio stuff posted in this forum,
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Re: Bike jerking issues CARB?...

#33

Post by jellero »

no new ideas but if timing is too far advanced it could cause this to happen. "gear lash" is what we used to call this but that was usually from a loose primary chain or starting in second with about any bike, truck, anything. so yes, gearing down would help. the easiest way would be to go down a tooth on motor pulley but they aren't cheap and you'd need to move trans back a bit.
what happens when you just rev it in neutral? any kick back out of carb or hesitation?
so you have no slack in driveline, timing is correct, fuel is fresh... i know nothing about this motor but if you have points, clean them, condensers, replace them. are you by any chance running "heavy duty" clutch springs? unless slipping is a problem i'd swap them out for stock. clutch plates clean? good luck... j
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Re: Bike jerking issues CARB?...

#34

Post by itsRICH »

all clutch components are new, its not slipping, dont think i have points, its an automatic ignition. she runs fine at idle when i give it throttle. and when in the mid range of first throttle response is fine, no hesitation. i found some rear sprockets that will work for my bike, i currently have a 51 tooth rear, and i think a 23 tooth tranny, and hte rear ones are like 20 bucks, not bad at all. im getting ready to do the math on this forum to see what my ratio is, and guesstimate what tooth count i need to get for the rear
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Re: Bike jerking issues CARB?...

#35

Post by jellero »

a 23 is low... i had a 25 or 26 but i have no idea what the belt system is on yours. one tooth on the trans does way more than one tooth on wheel and i don't know if you can go smaller on wheel anyway. j
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Re: Bike jerking issues CARB?...

#36

Post by itsRICH »

I found a 45/47/50 tooth for the rear, im running the 2" 8mm BDL open belt drive setup w/ 5 finger clutch. but you saying a 23 is too low is helpful
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Re: Bike jerking issues CARB?...

#37

Post by itsRICH »

olpanrider wrote:
itsRICH wrote:Ohh, that makes sense, would you do both tranny and rear tire or just one or the other, ive got a pretty large one on the rear right now

you have to count the teeth.. then divide drive into driven to get the ratio.


a common setup would be 51 rear 22 trans or 51 rear 23 trans


51÷22=2.318 final drive ratio
So ive got a 51 rear and 23 trans, what do you think is the issue? should I decrease the rear sprocket size to about a 47 tooth?
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Re: Bike jerking issues CARB?...

#38

Post by olpanrider »

absolutely no reason a 51/23 shouldn't work.
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Re: Bike jerking issues CARB?...

#39

Post by PanPal »

47 on the rear would be a taller gear? And you have to re rivet or bolt and true that rear sprocket. you should go down on the trans or up at the rear wheel to get lower gearing. 5 finger clutch is suspect! They are more difficult than a 3 finger to set.
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Re: Bike jerking issues CARB?...

#40

Post by itsRICH »

Its not like the clutch is slipping tho, and im pretty sure its not too tight, shifting is fine, and again once i increase speed/rpm its fine. Talkin with a buddy of mine, he thinks its the intermediate in my SS E and that its too lean, not alowing enough fuel in at the lower rpms, which is why when rpm increases when the main jet takes over its fine, also when i increased my idle speed it got a little better, still gonna try to adjust the carb better, to see if it clears it up, it might just be i need to incsrease my intermediate jet
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Re: Bike jerking issues CARB?...

#41

Post by itsRICH »

He also thinks my timing could be retarded a littl too far, so i will check that out as well. Might have to advance it a little bit
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