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Discussion Starter #1
Won't rev past 10K and doesn't return to idle after reving. I have rebuilt my carbs, 110 main jets....no air filters, henning-jemco two into two exhausts. Points ignition, new points. timing set, advancer is in good working order. Any ideas?
Brad
 

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brad, welcome to to the board!



10k is about the top anyway. it should rev past there though. but not much. timing issue? hows the motor? rings/compression will cause problems like that. try pulling the cover off of the points. sometimes they will arc to the cover. thats why it has that coating on the inside.

id suspect a leaking jet seal for the over rev. ive had problems before with them siphoning gas past the jet and letting the revs stay up. sometimes you have to force them in, and it mungs the o ring when you do. or they dont actually go in all of the way.

keep us posted. im sure the neighbors love you!

jc
 

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brad, welcome to to the board!



10k is about the top anyway. it should rev past there though. but not much. timing issue? hows the motor? rings/compression will cause problems like that. try pulling the cover off of the points. sometimes they will arc to the cover. thats why it has that coating on the inside.

id suspect a leaking jet seal for the over rev. ive had problems before with them siphoning gas past the jet and letting the revs stay up. sometimes you have to force them in, and it mungs the o ring when you do. or they dont actually go in all of the way.

keep us posted. im sure the neighbors love you!

jc
 

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Discussion Starter #5
imslow, it's a race bike. Joe, yeah all the "blue hairs" really love me! I will go back and check out all my jets and maybe check the points running at night for arcing. The engine is a fresh rebuild. Someone else has suggested it might be a ground issue with the condensor....don't know about that but might as well check that too!
 

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Discussion Starter #6
imslow, it's a race bike. Joe, yeah all the "blue hairs" really love me! I will go back and check out all my jets and maybe check the points running at night for arcing. The engine is a fresh rebuild. Someone else has suggested it might be a ground issue with the condensor....don't know about that but might as well check that too!
 

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look carefully at the point's contacts

note ANY metal transfer

and note if from movable to stationary

or vice versa

post results here

I however, do agree on the 10K, especially without electronic ignition

several very good, and crisply tuned, stock cammed ones, I had would only turn 9500 or so, under load

however, are you sure the valve spring seat pressures are spot on?

did you grind the seats during the rebuild?

new springs and properly shimmed?

tired used springs and you're pissing in the wind
 

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look carefully at the point's contacts

note ANY metal transfer

and note if from movable to stationary

or vice versa

post results here

I however, do agree on the 10K, especially without electronic ignition

several very good, and crisply tuned, stock cammed ones, I had would only turn 9500 or so, under load

however, are you sure the valve spring seat pressures are spot on?

did you grind the seats during the rebuild?

new springs and properly shimmed?

tired used springs and you're pissing in the wind
 

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Discussion Starter #9
Yes, a valve job and old springs, so you may be on to something there. I will look at those contacts tonight. Thanks guys.
 

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Discussion Starter #10
Yes, a valve job and old springs, so you may be on to something there. I will look at those contacts tonight. Thanks guys.
 

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carb slides hanging up. did you try honing the surfaces with toothpaste to get better action? cv carbs suck

10,000 is outta control. try not pullin past 9,500 with the points.... kaboom

matt
 

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carb slides hanging up. did you try honing the surfaces with toothpaste to get better action? cv carbs suck

10,000 is outta control. try not pullin past 9,500 with the points.... kaboom

matt
 

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quote:Originally posted by monkey

carb slides hanging up. did you try honing the surfaces with toothpaste to get better action? cv carbs suck

10,000 is outta control. try not pullin past 9,500 with the points.... kaboom

matt
Please tell me more. I have never heard of the benefits of honing the surfaces of my carbs with toothpaste. I
 

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quote:Originally posted by monkey

carb slides hanging up. did you try honing the surfaces with toothpaste to get better action? cv carbs suck

10,000 is outta control. try not pullin past 9,500 with the points.... kaboom

matt
Please tell me more. I have never heard of the benefits of honing the surfaces of my carbs with toothpaste. I
 

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yeah dude

I crashed a while ago at our end of the season race... into sand/ dirt etc etc... I cleaned my carbs out very well... but when i went to fire it up next season... the slides were hanging up.... my technical advisor...aka father in law... suggested I try honing the slides and the opposing surface of the carb interior with toothpaste. we used alittle very fine wetsand paper ( 400 grit)... It worked perfectly... apparently I managed to score the slide and inner surface with the sand and dirt enough that things would catch.

check it out.

matt
 

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yeah dude

I crashed a while ago at our end of the season race... into sand/ dirt etc etc... I cleaned my carbs out very well... but when i went to fire it up next season... the slides were hanging up.... my technical advisor...aka father in law... suggested I try honing the slides and the opposing surface of the carb interior with toothpaste. we used alittle very fine wetsand paper ( 400 grit)... It worked perfectly... apparently I managed to score the slide and inner surface with the sand and dirt enough that things would catch.

check it out.

matt
 

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the toothpaste has a mild abrasive in it enough to smooth out the shite.

now don't go flossing your jets and tickling your round slides with mouthwash....
 

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the toothpaste has a mild abrasive in it enough to smooth out the shite.

now don't go flossing your jets and tickling your round slides with mouthwash....
 
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