Cam Chain Adjuster

[trbig]

If anyone else has come up with this or heard about it, I haven't. As many of you know, Bohn Fraser had some problems with his adjuster that ended up with some bent valves. He took it to a mechanic that has built hundreds of these motors for legend racers.

When he was through, he installed an adjuster from an FJ1200 motor. It doesn't fit EXACT... but close enough to work. This adjuster is longer and resembles a phallic symbol a bit.. but who really sees it? AND... this adjuster is automatic and ratcheting! That means no adjusting.. EVER! If you ever start hearing a lot of cam chain noise, it means that you have stretched your chain beyond the limits and need a new one. Bohn said he never heard any cam noise on this last trip to Colorado. I had to adjust mine on the way home in a 90+ degree parking lot. Plus.. no set screws in the side to leak oil.

There is a downside though. This adjuster will work on an XS... but not an XJ. The XJ has an extra bar across the front for frame stiffening that goes right in front of this adjuster and it won't work. Anyway.. I thought it was a great idea and thought I'd pass the info on...





Tod

[Silent]

What year FJ motor did that ome from? I've been thinking about changing my CCT recently anyway.

[dbeardslee]

Tod - I modified a stock tensioner and got rid of the spring assembly. This setup doesn't leak, and doesn't slip. I adjust it to finger tight, and have verified with the valve cover off that this yields correct tension on the chain (1/4" vertical chain movement). I measured it against the stock adjuster and found that, when I've got 1 1/8" of thread left (measured from the locking nut to the end of the thread, it's time for a new chain. The picture is of my first attempt - I have since added a longer carriage bolt with a locking nut. I also added a thick neoprene washer JB Welded to the end of it, but I don't think that was necessary - but you get the idea. It's a cheap, easy mod that works real good. Still have to adjust it periodically, though.

[FJ111200]

What year FJ motor did that ome from? I've been thinking about changing my CCT recently anyway.

FJ cam chain tensioners are all the same no matter what year, from FJ1100 through the 1200's and on through the XJR1200 and 1300's.

[psycoreefer]

I just did an e-bay search and I thought it was kind of funny that the first result is a APE manual cam chain tensioner for FJ's. Looks a lot like Dbeardslee's solution. IF the FJ tensioners do fit and anyone wants a manual one with building it themselves there are these APE ones that should work I guess.

[trbig]

Yeah, I saw that modification you had done, but you still have to pull the sidecover, turn the crank to the "C" and do the adjusting. This one is completely automatic and hands free.

I will be doing this mod though to my XJ since the FJ adjuster won't work for me. With the adjuster tightened to spec, under hard riding and high RPM, my adjuster gets pushed out and I have to re-adjust it in the middle of a ride. How do you keep the oil from chasing up (Down) the threads of that carriage bolt and leaking?


Tod

[dbeardslee]

Tod - how do you know when your chain needs to be replaced? You sure you don't like the FJ mod 'cause it makes your bike look like the John Holmes of XS's?

[trbig]

LOL. Honestly, I would do that FJ mod if I could, but you can't do it to the XJ with the way the frame is designed. You'd know the chain needed replaced when you starting hearing a lot of chain/cam noise... meaning the adjuster can't adjust any more.

And besides.. what sticks out the front isn't nearly as important as the huge balls these motors have! (You know.. as in ball bearings.. yeah that's what I meant..)


Tod

[Guy_b_g]

I just looked at an FJ1200 cam chain tensioner on Ebay..didn't look in that good of shape and there was only 1.

Then I looked at the APE manual adjuster...too much money...but it lists several other bikes that the APE adjuster also fits...including certain years of the R1, and R6...and if the FJ tensioner fits...and the APE is a replacement to the FJ, R1 and R6...it follows that an R6 tensioner should work too.

Here's the list of applications for the Ape adjuster:

YAMAHA:

YZF600 R6 1999-2005
FZR600 1989-1998
YZF750 1994-1998
FZR1000 1987-1996
YZF1000 1996-1997
YZF1000 R1 1998-2003
FJ1100/1200 1984-1993

I just bought an R6 tensioner on Ebay for $20...they are plentiful, as are the R1 tensioners.

The R6 tensioner doesn't look as long as an FJ tensioner in the photos...maybe it'll work for those with XJs also?....

I will let you know how it works out upon installation.

[Guy_b_g]

FZR600 tensioners look promising too...and are even more plentiful and cheaper...but appear longer than the R1 and R6 tensioners (at least in the photos)....maybe someone here will try one.

[Yahman]

Guy_b_g,

Please take some measurements before you install it.

Larry

[Guy_b_g]

LOL...I'm not gonna just shove it in there and hope it works! Of course I'll measure and compare and if necessary modify.

[tarzan]

Schwiiing!

[Dragon Tamer]

Tod,
Thanks for the idea and the picture. Looking at the picture motivated me out of my chair and into the shed for a looksee. The tensioner on my 650 Maxim looks to be the same thing but possibly a touch shorter. As I have a parts 650 sitting around here somewhere that one will come out today and I will try it on one of my 1100's to see if it fits.
I will keep you posted as I, like you, am just a bit weary of the parking lot chain adjuster dance.

[oldnortonrider]

Yeah, I saw that modification you had done, but you still have to pull the sidecover, turn the crank to the "C" and do the adjusting. This one is completely automatic and hands free.

I will be doing this mod though to my XJ since the FJ adjuster won't work for me. With the adjuster tightened to spec, under hard riding and high RPM, my adjuster gets pushed out and I have to re-adjust it in the middle of a ride. How do you keep the oil from chasing up (Down) the threads of that carriage bolt and leaking?


Tod

'Trbig'~~I made this same setup, like 'dbeardslee's mod, a few years and about 20K miles back. To not have a problem with oil leak, you can fashion a pretty good gasket/grommet from a piece of fuel line that slips down over threaded end of bolt sticking out from end of housing, and will fit fairly nicely down inside of the housing. Add some kind of flat fiber or nylon washer between the flat metal washer and end of housing. Not long ago, I did quit using the "fuel line" part, because I ran onto some kind of neoprene grommet that did fit snug down around the threaded shank part of the bolt and flared out wide enough to get a good seal when the flat metal washer was pushed down tight with the hex nut against housing end. Just like any O-ring material type that's up against hot metal, usually a good idea to replace this "flex-gasket" setup fairly regularly. The nut doesn't hold anything, except to be there to clinch down the 'oil seal'. Lock bolt on the side does fine to hold the bolt; doesn't take much to lock down against the 'threaded' shank. The nut screwed down on washer(s)~~tighten it down just enough to put a good squeeze between the metal and "soft" washer setup.