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I've been reading and viewing a lot about cam tensioners on the big twin, whether it's spring loaded or hydraulic, is there any kind of remedy to this like getting rid of the tensioner all together in place of a better system, or do i have to hope and pray it doesn't fall apart on me. I've had a sportser, loved it, needed money, had to sell it, I'd like to get a bigger bike but if this problem couldn't be fixed, i may have to stay with a sporty, i do like the 72, however I would like a bigger bike. Any answers, comments would be greatly appreciated.
 

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s s sells complete sets- cams and gears- or you can by just gears for other makes of cams designed for gear drives-stroll around ebay

there is really nothing wrong with the stock hydraulic ones- the issues were on early spring loaded ones,but they now make kits to install the new style cam plate and tensioners on the older 88cu motors that had the spring
 

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Where can I find these gear drives? Website, catalog, part number
S&S, Andrews. Pretty much anybody that makes H-D cams offers a gear drive.

They don't work in any motor though. The crank run out has to be pretty low for them to work. The chain drive system allows the crank to be less true. That is, if there is a little wobble in it, the chains have enough slack for it not to matter. With a gear drive, the gears are lashed against each other. If crank wobbles, it's not only doing to be noisy as hell, it will stress the crank bearings to premature failure.

Personally, I don't see the problem with the chain and tensioner system. It was mostly addressed after the first few years of the TC. If you buy a 96" motor or newer, it has the hydraulic design. Those have been shown pretty dependable up to 75-80K or more.
 

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Checked mine for wear at apprx. 30K. Very little wear. Plan to look again at 50k.


PS: HD changed the material on shoes for the old spring loaded tensioners. Understand they last longer than original material. The chains themselves were part of the major cause of failures. Sharp edges cut into the shoes. They also were changed to a different type.
 

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If your crank run out is within tolerance go with the gear drive. I installed the S&S510 gear drive cam set, that is about as big as you can go with out having to do head work. no more plastic shoes to worry about. If you dont want to spend the money, just take a peak at them every time you change your oils, and replace as necessary. Some go quickly some last a long time, its a crap shoot really. Hope this helps
 

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2007 is the year they switched to the new style , they are pretty reliable compared to the spring tensioners .

The other thing about a gear drive to know is you may have an acceptable run out spec .003 or less but if your crank weights ever shift , it can happen though not real common, you may no longer be under .003 run out , and you may not know it happened.
 

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I did the upgrade last November. Not hard to do. The rear tensioner shoe was toast and the bike is a 2001 and only had 26k on the odo. I did the SE cam plate with the hydraulic tensioners and the high volume oil pump. I was thinking about the gear drive like I had in my 99 FLHR and did the run out on my crankshaft with a mag base and dial indicator. Had half a thousandth! Still decided to go ahead with the chain drive. Oil pressure cold at start up is around 48psi and when warm idling in traffic is around 20 or so. I'm glad I did it!
 

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I did the upgrade last November. Not hard to do. The rear tensioner shoe was toast and the bike is a 2001 and only had 26k on the odo. I did the SE cam plate with the hydraulic tensioners and the high volume oil pump. I was thinking about the gear drive like I had in my 99 FLHR and did the run out on my crankshaft with a mag base and dial indicator. Had half a thousandth! Still decided to go ahead with the chain drive. Oil pressure cold at start up is around 48psi and when warm idling in traffic is around 20 or so. I'm glad I did it!

Amen RK! When mine was done at 32K, the original front spring tensioner fell apart in my hand! Glad I went hydraulic.
 

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The problem was mostly the chain design, not the spring tensioner. Early models (spring tensioners) used what is called a "silent" chain (see first att.) basically just steel plates that act like a grinder on the tensioners. With the introduction of the 96" engine and hydraulic tensioners, they went to a roller chain (see 2nd att.). The side plates of the roller chain will wear into the tensioner a little, then the rollers prevent further wear, as they just slide across. Yes, the Hydraulic tensioner keeps less pressure on the tensioner, which also helps.


Harley Twin Cam Engine Chain Secondary Cam Drive 25607 99 | eBay


Harley Davidson Roller Cam Chain and Gears | eBay
 

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It's also long been surmised that those chain plates developed burs with rough edges towards the end of a run as the cutting dies got dull. This also supports why there is such a wide range of failure mileages. If your chain plates were cut on a fresh die you got smoother chains that weren't as abrasive on the tensioner shoes , dull dies = rougher edges chewed the shoes up much faster.
 
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