S&S 551 gear driven cams

[Loner]

You don't have to check runout at all if you go with the 551G cams. They are bolt in which means you don't have to do a thing to ur engine. Now if you go with higher lift cams you have to check valve clearance and you have to install stronger valve springs. I'm not going to get into that crap! Besides from what I'm seeing about those S&S 551G cams, they are PERFECT for getting a heavy bike moving fast. They call it a torque cam. Torque gets you there quick and then HP makes you go fast.
BTW with these 551G cams they say you can use your stock push rods, but I HIGHLY recommend that you spend the $190 extra dollars and get the Screaming Eagle adjustable push rods.

[Nick-O]

You absolutely DO need to check run out before installing gear driven cams on any twin cam. We have been installing them for years, and we check run out on every twin cam, regardless of year or displacement. We do a ton of 510's, and now 509's, and since some years are so prone to walk, we keep 255's in stock in case we tear down and the bikes do not except the gear drives.

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[roadwolf]

I have yet to see a 2007 or newer twin cam with less than .006 run out the max is .003.The best way to check run out is with a fueling crankshaft indicator. It is not pretty if you don not check run out and it exceeds the max .

[dbell66253]

Thanks Nick-O and roadwolf for confirming what I previously posted. Loner, the run out has nothing to do with the lift, you must be thinking about valve springs or something. With gear drive the tolerance has to be a whole lot closer than with a chain, gears aren't as forgiving.

[prodrag1320]

Originally Posted by Loner

You don't have to check runout at all if you go with the 551G cams. They are bolt in which means you don't have to do a thing to ur engine. Now if you go with higher lift cams you have to check valve clearance and you have to install stronger valve springs. I'm not going to get into that crap! Besides from what I'm seeing about those S&S 551G cams, they are PERFECT for getting a heavy bike moving fast. They call it a torque cam. Torque gets you there quick and then HP makes you go fast.
BTW with these 551G cams they say you can use your stock push rods, but I HIGHLY recommend that you spend the $190 extra dollars and get the Screaming Eagle adjustable push rods.

please dont tell me your working on anyone but your own bike.pinion run-out MUST be checked on ALL gear drive applications and has NOTHING to do with cam lift,its got to do with the outer gears eating each other up.another example of why you really need to check out who`s working on your bike

[prodrag1320]

Originally Posted by Loner

I put gear driven cams in another bike of mine and just loved the quick response. I also like the fact that you remove the chain shoes. Also, the bike idles different and sounds different with gear driven. I know when a bike has gear driven cams in it, and I just say that's the sound of HP.
It's just my preference. I know chain driven are very good too, it's just I don't like chain lag.

im a big fan of geardrive cams,but your wrong here too,if you can hear a difference,your gears are too tight (a gear whine),or too loose (ticking),not only do you need to check run out,but gear back lash must also be checked to make sure oversized or undersized gears are not needed.please explain "chain lag" too

[tmd]

Originally Posted by Loner

I put gear driven cams in another bike of mine and just loved the quick response. I also like the fact that you remove the chain shoes. Also, the bike idles different and sounds different with gear driven. I know when a bike has gear driven cams in it, and I just say that's the sound of HP. It's just my preference. I know chain driven are very good too, it's just I don't like chain lag.

Gear driven or chain driven there is no difference in reponse. What you felt was the reponse of different cam.

If your referring to the whining noise of the gears then what you hear is improperly set gear lash, not the sound of HP.

If the bike your wanting to install gear drive cams is a 2007 or newer for the sole purpose of eliminating the tensioner shoes then your just wasting money. The hydraulic tensionser dont have the issues that the spring loaded tensioners had.

[caboverbob]

I have questions for the 3 experienced engine builders posting to this thread. I recently bought a 2001 RG w/gear driven cams, I must assume that runout was checked at the time of install, but can or does it change over time ?

I spent my childhood around street rods and drag racing and always loved the sound of a Jackson gear drive set-up, but based on your statements here, I have to assume that if the noise is that noticeable maybe they are not set up correctly ?

Mine in my bike make just a little noise, nobody notices except me, should I be concerned ?

Thanks guys

[prodrag1320]

sure it can change,thats how the lower ends get out of spec to begin with.if the bike gets abused (holeshots,downshifting hard,ect)if yous is making a little noise i propley wouldt sweat it,but pulling the cams out & checking run-out isnt a big deal either