The old gear-driven cams vs hydro tensioners question
#1
The old gear-driven cams vs hydro tensioners question
After reading this board and others, and contemplating going to gear-driven cams in my 2007 FXDWG, I've decided to stick with the chain-drive, hydro-tensioners.
My shaft runout is within tolerances, now. But my thinking is that if I don't have it trued, plugged and welded, it eventually will go out of tolerance and eat up the gear drive.
Am I on the right track here?
My shaft runout is within tolerances, now. But my thinking is that if I don't have it trued, plugged and welded, it eventually will go out of tolerance and eat up the gear drive.
Am I on the right track here?
#2
If you're interested in performance then gear drive is the way to go. A chain, depending on the tensioner/chain wear, can effect valve timing. This could become a problem with higher performance engines. There is also a degree of power loss with a chain.
U are correct though - runout is more critical and could increasingly become a problem with a gear drive.
U are correct though - runout is more critical and could increasingly become a problem with a gear drive.
#3
2007 was the first year of off shore sourced cranks and there has been a reported higher incidence of tweaking cranks that year than in subsequent years; no statistics to back that up. However, if you lurk on all the other H-D forums, it does ring true.
Having said that, your concern is valid with regard to increasing crank runout but your crank may be fine; that's the issue, you just don't know. The upside of the hydro tensioner/roller chain setup is that even if your crank runout increases to unacceptable limits, you will most likely know things are going south before the motor grenades; not so with gears. Runout increases with gears, a tooth breaks and bad juju follows.
Another upside of the hydro setup is that there are no gears to press on/off; much easier install for the DIY guy.
The usual line regarding loss of power with chain drives is pretty much an urban legend. Sure, there is a parasitic loss to drive the chains but there is also a parasitic loss to drive the gears. Gear drives to provide more precise cam timing but how that relates to performance will not register on the butt dyno and it is debatable that it will show up on a dyno chart.
You are on the right track.
Having said that, your concern is valid with regard to increasing crank runout but your crank may be fine; that's the issue, you just don't know. The upside of the hydro tensioner/roller chain setup is that even if your crank runout increases to unacceptable limits, you will most likely know things are going south before the motor grenades; not so with gears. Runout increases with gears, a tooth breaks and bad juju follows.
Another upside of the hydro setup is that there are no gears to press on/off; much easier install for the DIY guy.
The usual line regarding loss of power with chain drives is pretty much an urban legend. Sure, there is a parasitic loss to drive the chains but there is also a parasitic loss to drive the gears. Gear drives to provide more precise cam timing but how that relates to performance will not register on the butt dyno and it is debatable that it will show up on a dyno chart.
You are on the right track.
Thread
Thread Starter
Forum
Replies
Last Post
Quiet Thunder
General Harley Davidson Chat
7
11-27-2016 12:12 PM