crank runout

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May 17, 2016 | 03:31 PM

hetkehog

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From: bloomer wi

crank runout

What is the runout allowed on the crank to use the S&S gear drive cams?

May 17, 2016 | 03:41 PM

hetkehog

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From: bloomer wi

thank you djl. you answered my question in the tensioner post right below this one. .003. like i said im a machinist and .003 is a **** ton. when i check mine, if its over .003, i would have a hard time even putting chains back in. to me that is to far for any runout. maybe not but i deal with .0005 all night so .003 is a lot

May 17, 2016 | 04:34 PM

djl

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From: san antonio

Quote:

Originally Posted by hetkehog

So, you think .003" is a lot? That was the HD spec for warranty purposes up to the '07 model year when that spec changed to .012" which was coincidental with moving the supply source for cranks offshore. .003" is still the "recommended" max total runout for gear drive cams but I do know a couple of guys that have run gears at .004". Andrews makes over and under size gears which are sometimes required for proper fitment. I am running gears in one bike at .0025" with no issues. Chains can tolerate much more runout.

May 17, 2016 | 06:20 PM

hetkehog

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From: bloomer wi

yes I understand that chain can withstand more. like I said. im a machinist, I hold +/- .0005 which is .003 times 6. how long will a motor last with .003 or under runout with 30,000 miles?

May 17, 2016 | 08:51 PM

djl

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From: san antonio

Quote:

Originally Posted by hetkehog

yes I understand that chain can withstand more. like I said. im a machinist, I hold +/- .0005 which is .003 times 6. how long will a motor last with .003 or under runout with 30,000 miles?

I think you mean that .003 is .0005 time six??

Long enough to wear out the top end if the motor is properly maintained. Even a trued crank will show .0015" runout. You have to remember that the HD vtwin is not much more than a tractor motor; same basic design for 75 years and a motor that rarely sees 5000 rpms and in that world, .003" is pretty tight......

Last edited by djl; May 18, 2016 at 11:26 AM.

May 18, 2016 | 06:04 AM

Hillsidecycle.com

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Quote:

Originally Posted by djl

I think you mean that .003 is .0005 time six??

Long enough to wear out the top end if the motor is properly maintained. Even a trued crank will show .00015" runout. You have to remember that the HD vtwin is not much more than a tractor motor; same basic design for 75 years and a motor that rarely sees 5000 rpms and in that world, .003" is pretty tight......

I agree.
Having served thru a NYS Toolmaker apprenticeship in the mid '70's, and having manufactured the driveshaft ship-sets(4 pcs.) for the AH-64 Apaches for Hughes, and holding .0005", T.I.R. and .0005" on the bores...........on the 10' fters!!!
Knowing when to be fussy and what your working with, is a balance that comes over time.
Scott

Last edited by Hillsidecycle.com; May 18, 2016 at 06:06 AM.

May 18, 2016 | 06:30 AM

prodrag1320

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From: deland,florida

.0035 is where we like not using gear drives,we have installed them at .005 once (against our recommendation & no warranty),bike is still fine after 3 years.