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Old 02-18-2012, 05:36 PM
crazy steve crazy steve is offline
Join Date: Jan 2009
Location: Beautiful outer Yelm, WA
Posts: 7,932
Automatic Cam Chain Tensioners

I've tried to consolidate all the information about these since Ivan first came up with this mod. He gets the lion's share of the credit for finding the first unit that would fit, but which has since been expanded to at least three part numbers found on a bunch of bikes! The various 'types' and what they came on will be in following posts, so finding one shouldn't be too hard.

Here's the mod..... Starting with part of Ivan's original post.


One night in the deep recesses of my garage, I was looking over my Venture, and noticed the tensioners had the same bolt pattern and mounting flange as on the XS. I eBayed a set for $20, which is a pair, since the V engine has two chains. These have a plunger with a ratcheting mechanism with a spring. The plunger will move out, but not back. There is a plug on the outside of the tensioner with a spring under it. Installation is as simple as removing the plug and spring, pushing the plunger in, bolting it up (with the engine at the "C" mark of course), and reinstalling the spring and plug. I heard it ratchet into place, kinda sounded like a zip tie.


Below is the various types; there's three units that we know work, and they are the V-Max/Venture units, a very similar unit that was sourced off a Vision, and a unit off a Raptor. The Vision unit needs a slight mod, the V-Max and Raptor units might, and I'll note those.

Here's a A/B comparison between the V-Max/Venture and XV550 Vision tensioners. All pics have the Vision unit (found by Natemoen) on the left.


You can see the slightly different 'offset' here, but it's too small to make any difference I can see. The big difference here is the bolt center-to-center; the V-max can be a direct bolt-in, the Vision has the holes .070" further apart. So the Vision unit needs a small alteration. You might have to slightly file the V-Max mounting holes (I did) if the bolts don't screw in easily. For the Vision unit, do the alteration in the upper hole, and file the hole down and to the left slightly for the best fit. The Vision unit will only fit one way, so test-fit to see which hole is 'top'.


The Vision unit is .130" longer than the V-max internally. I doubt that this would be a problem, maybe with a new cam chain. I know in comparing this in length to OEM units I have that are 'set', this will fit. The Vision unit has a much softer spring too; you can easily fully compress that one, the V-max takes some effort. Both seem to use the same plunger.


The other big difference. The Vision unit has the plunger/ratchet rotated about 45 degrees.

The Raptor unit (found by Codylane)... at least one user reported that the bolt holes were a bit 'tight', so if you can't screw them in by hand, you may need to slightly file the holes

Has the same offset as the XS11 tensioner

To install any of these.... (make sure the bike is level before starting, preferably on the centerstand)

1. Remove timing cover
2. Turn engine clockwise until the "C" mark lined up with the pointer
3. Remove the 2 bolts (5mm) from the OEM cam chain tensioner
4. Remove the cam chain tensioner and paper gasket from the engine
5. Loosen and remove large bolt (19mm I think) and underlying spring from the front of the auto tensioner.
6. Depress the ratchet arm on the tensioner and push the plunger all the way back in.

7. Install the body of the auto tensioner with a new gasket or your favorite sealer into the engine and secure the body of the tensioner with the bolts. You do need to pay attention here to the bolt length; the OEM bolts are too long for the V-Max units and need to be shorter, the Vision/Raptor units may be able to use the original bolts. Make sure your bolts don't go into the cylinder any further than they did with the stock cam chain tensioner or leaks and/or broken bolts will result. This is critical!!
8. Insert the spring and bolt and tighten down.

Caution! There have been several reported instances of the cam timing 'slipping' when changing the cam tensioner, so it is highly recommended that you remove the cam cover also and verify that the cam timing is still correct after install. After install, turn the motor by hand at least one full revolution then check that the timing marks all line up. Details are here:
Note that this is the recommended procedure as per the factory manual when changing the tensioner. You have been warned!

That's it! No more cam chain adjusting or oil leaks. One last thing to note is the spring tension isn't the same on all units; the V-Max/Venture unit has the stiffest spring, followed by the Raptor, then the Vision. The Vision unit is pretty close to the same tension as the OEM spring. This probably won't make any difference as there's been no reports of problems with any of these, but you might see faster cam chain guide wear with the stiffer springs. The concensus is all will work equally well.
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Last edited by crazy steve; 05-13-2013 at 03:04 PM.