Can someone explain the difference between gear driven cams and chain? Which is better? Pros vs. Cons?

Thank you,

 

They are alternative solutions to fixing the wear problems on early twincam engines that had spring-loaded tensioners. Later twincams come from the factory with an upgraded chain set-up with hydraulic tensioners, that can be retrofitted to earlier engines. They seem to solve the problems and bolt straight in.

The gear driven cams are an after-market solution to the tensioner problem, using gears instead of chains. They will bolt in to many engines, but not all. The reason is that Harley build the crankshafts at the factory for chain drive, not gears. Gears require the crankshaft to have less run-out than the factory builds them to, so before buying a gear set-up check run-out on your crank to see if it is in spec for the gears.

Hope that helps!

 

Another point on the gear driven cams is that you can select a bit more of a lift and get away with it due to the design. Doesn't one actually turn in a differt direction, or is that thought due to my staying up late last night and drinking way past my limit?

 

Cons.....will not work with excessive crank run-out,can be a little louder then the stock chain set up,more expensive.

Pros...less moving parts,positive engagement,less backlash,zero maintenance.

 

Thank you much for the info. This is the first HD for me so I wasnt sure. Looking at cams options for my 2009 FLHX. Right now looking at Woods TW-6-6 orthe newer TW-555. I appreciate all your information. I assume for my motor just stay with the chain drive.

 

Hey JT can you keep us posted on the cams? Are you looking at doing the 103 kit? I have same bike, and trying to decide on which kit etc....

 

The advantage of the hydraulic over the spring load cam chain tensioners is the fact that the spring type drives on a flat link chain that always slides and hence more wears. The hydraulic uses different sprockets designed for the roller chain that is really the upgrade. Once the side links groove in and the rollers of the chain roll across the shoe, the shoes should last life of the motor. Just my opinion but I believe Harley put the hydraulic part it for a smoke screen to cover their butts when they saved 10 cents by using the link chain. The gears will create more load but are more accurate at high RPM. Some Harley engines have too much run-out for gears. If you have a lot of run-out you will hear it in a gear drive setup. Its not noticeable in chains since the delrin shoes dampen slightly. I personally do not believe a gear drive will outlast a roller chain.

 

your right, the gear drive might not out last the chain, might last longer.

WEAK LINK.... is the tensioner shoe and with enough time and or miles it will wear out and eventually fail. Resulting in tensioner parts and pieces in the motor, oil pump, etc.

 

How hard is it to swap out to hydraulic cams vs spring tensioners . And cost between the two thanks guys slick hd

 

I was in this position last year on whether to go with gear or the new hydraulic setup from HD. I went with the hydraulic chain setup and has worked out great.