so gear drive cam spec is .3 the Harley mechanics say anything under .4?!?!?!?!

[dynaloves88]

My crank run out on my dyna is just under .4 im confused who's right

2000 FXD 88 twincam

[kd]

do you mean .004?  .4 is almost 1/2 inch.  The standard seems to be .003 but I do know of a couple that were more and one that just did it and got lucky. I guess it also depends on if you beat it hard or have some bad downshifting habits also. What year is the Dyna?

[rageglide]

You can hear .003", You'll hear .004" a bit more.  If you like that gear drive sound go for it, but if you don't, you should probably avoid gears. 

[hotbo]

my dads 03 fatty is .003 is this good enough for Gear drive cams??? 

[05fatboy95]

I did gear drive cams on .0035 last winter. You can't hear anything and no issues 15k miles on it.

Crank was trued weld plug and balanced 30k miles ago.

[dynaloves88]

do you mean .004?  .4 is almost 1/2 inch.  The standard seems to be .003 but I do know of a couple that were more and one that just did it and got lucky. I guess it also depends on if you beat it hard or have some bad downshifting habits also. What year is the Dyna?

2000

[rageglide]

I did gear drive cams on .0035 last winter. You can't hear anything and no issues 15k miles on it.

Crank was trued weld plug and balanced 30k miles ago.

Wait.  .0035" crank run out yet you say crank was trued?   I'm confused.

I had .003+" run out and you could noticeably feel the tight/loose spots when rolling the motor over. You could hear it.  But it was fine, ran that for about 20k miles and when I pulled the cams the crank was .008" out.  Obviously the drive gears wore in over time.

[05fatboy95]

Yup it was trued and all by a company I would never use again.  Back before I knew any better. First crank when out when cam chain tensioners let loose.

[truck]

Are you aware you can buy undersize pinion gears that will help the run out issues?

[rageglide]

Ah.  Got it.  Yeah WTH, you can get .003 from the factory for free!  lol  My '12 had .0065" when I did the cams 10k ago. 

Anyway... I ran the gears for long time and I liked the subtle whine it had, maybe you had little looser fit 05fatboy95.

Truck,  yeah I had to go to an undersized gear.  Still get a tight/loose condition unless you go undersized to the point of too loose.  When the gear was at it's loosest, it was pretty loose imo, I wouldn't want to run it much looser than it was.

[koko3052]

do you mean .004?  .4 is almost 1/2 inch.  The standard seems to be .003 but I do know of a couple that were more and one that just did it and got lucky. I guess it also depends on if you beat it hard or have some bad downshifting habits also. What year is the Dyna?

"Beating it hard or bad downshifting" has nothing to do with installing gear drives now, with the runout that it has!. May get worse... may not!
I personally wouldn't do gear drive with any more than .0025... LOCKED! just looking for trouble if you do.
I don't understand the "mantra" about gear drives in a street motor anyway... may just as well be an oil thread! 

[rageglide]

Gear drive made a lot of sense back before the -06 cam plate/tensioner change.  I never would have done gears if the newer tensioner option existed back then.

[05fatboy95]

The first time the motor was rebuilt with (2003 night train) 40k on it because of tensioner failure (30 days after service at dealer) and then 15k miles later the shoes where about shredded made me decide it's going to be gears.

.0035 and the gear fit was perfect. No more worries or issues aslong as the crank holds up to the abuse.

Now my 05 fatboy had enough run out at 15k miles to eat an oil pump, thrash lefty bearing and destroy my 95" with SE plate/pump kit. That now has a 4 3/8 crank done by silvermoon with gears that are quiet also. I don't know runout as BVhog built this one for me.

Gear drives offer me piece of mind.

[rageglide]

To clarify, I never would have done gears with my crank run out IF current option existed. 

If the crank is dead nuts a gear drive set up is very nice option.  At the time I just wanted to get rid of the crap tensioners.  If I could reuse the gear drive set I already own in my 2012 I'd do it IF crank was straight, but it's not an option... so it exists for a project bike down the road.

[1FSTRK]

It is not about who is right, It is about following the instructions for gear drive installation.
http://www.sscycle.com/files/2413/7034/0536/51-12341.pdf

From the the instructions

"The minimal required backlash for the gear set should be between .0005" and .001" and no more than .002" for
cold gears. Both gear sets should roll freely with no radial or axial binding."

I do not see how you can have no less than .0005 and then rotate the crank 180 deg. and have no more than .002 if your crank is going up and down .004-.005
One other note is I have watched the local build install these and due to manufacturing tolerances he has found that because the cam turns at half speed you need to check at every 90 degrees of cam rotation rather than every 180 deg. of the crank. 

[Jaycee1964]

The only way I would run gears is at under .001 and have a plugged\welded crank.  If it shifts with gears it'll make a mess vs. with a chain at least you'll have some give.  JMHO

[dynaloves88]

So I'm safe at .004 lol or better off with chain

[Jaycee1964]

So I'm safe at .004 lol or better off with chain

IMO no but it's your $$$

[1FSTRK]

Gears are for transmissions.

[les]

I think you should sit down and do the $$$ math.  Gear drive cams are very expensive.  If you estimate that you'd have to go back in about every 40K miles and replace the tensioners, I think you'll find that going to gear drive cams does not add up money wise.

First think if you're even going to keep the bike for another 40K miles.  If there is little chance of that, then why put gears.  Secondly, even if you did keep it for a second round of 40K miles, chain drive is still cheaper.

[kd]

To clarify, I personally will not be using gears in my 120 on the bench right now. That's because the Hydro tensioner is sufficient for what I'm doing. I would however like to point out that gears were the only option since inception and only since the twin cam has there been these types of problems in the cam chest.

do you mean .004?  .4 is almost 1/2 inch.  The standard seems to be .003 but I do know of a couple that were more and one that just did it and got lucky. I guess it also depends on if you beat it hard or have some bad downshifting habits also. What year is the Dyna?

"Beating it hard or bad downshifting" has nothing to do with installing gear drives now, with the runout that it has!. May get worse... may not!
I personally wouldn't do gear drive with any more than .0025... LOCKED! just looking for trouble if you do.
I don't understand the "mantra" about gear drives in a street motor anyway... may just as well be an oil thread! 

koko,

Doing the things I mentioned and including wheel hop after a burn-out or slamming the brakes on with the clutch engaged to avoid a collision, WILL cause wheels to shift in any multi piece assembly. Now, what I call beating it and what you call beating it may be 2 different levels of abuse but on this forum alone there is plenty of examples of these types of failures. My point was intended to be .... If you don't have a trued and welded set of wheels, and you beat on it (the way I consider beating on it) eventually the odds will get you and the collateral damage with gears may be more extreme. 

[Admiral Akbar]

To clarify, I personally will not be using gears in my 120 on the bench right now. That's because the Hydro tensioner is sufficient for what I'm doing. I would however like to point out that gears were the only option since inception and only since the twin cam has there been these types of problems in the cam chest.

do you mean .004?  .4 is almost 1/2 inch.  The standard seems to be .003 but I do know of a couple that were more and one that just did it and got lucky. I guess it also depends on if you beat it hard or have some bad downshifting habits also. What year is the Dyna?

"Beating it hard or bad downshifting" has nothing to do with installing gear drives now, with the runout that it has!. May get worse... may not!
I personally wouldn't do gear drive with any more than .0025... LOCKED! just looking for trouble if you do.
I don't understand the "mantra" about gear drives in a street motor anyway... may just as well be an oil thread! 

koko,

Doing the things I mentioned and including wheel hop after a burn-out or slamming the brakes on with the clutch engaged to avoid a collision, WILL cause wheels to shift in any multi piece assembly. Now, what I call beating it and what you call beating it may be 2 different levels of abuse but on this forum alone there is plenty of examples of these types of failures. My point was intended to be .... If you don't have a trued and welded set of wheels, and you beat on it (the way I consider beating on it) eventually the odds will get you and the collateral damage with gears may be more extreme. 

Welded wheels don't do jack.. Either go with plugging or SnS late wheels.

[wholehog]

So I'm safe at .004 lol or better off with chain

stay chain

[kd]

So I'm safe at .004 lol or better off with chain

stay chain

  .... and look into the hydro tensioner conversion with the upgraded pump etc.

[rageglide]

   Chain