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Discussion Starter · #1 ·
In reference to my earlier thread I started to strip out my cam shafts to replace some valve shims using the advice given by some of you yesterday.
I had my son make me up some pins in his workshop to lock the gears in tension. After checking all the clearances I found that I would have to remove both cams. My problem is the gears as they are fitted are not under tension and the holes do no line up. The bike was bought for me as a birthday project present from my wife and has only been ridden a couple of times before I started work on it. I can only assume that the previous owner removed the cams without locking pins and just replaced them as such.
After I remove the cams is there an easy way of getting the gears back in tension without doing damage?

A couple of picks to show you what I mean.

http://i590.photobucket.com/albums/ss350/FrankW_album/Leftsideinlet.jpg

http://i590.photobucket.com/albums/ss350/FrankW_album/Leftsideexhaust.jpg

FrankW
 

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When you pull the cam shafts out, you can wind the anti backlash gear back up. Triumph sell a special tool for this (it comes with the locking pins). It is basically a large stamped out wrench with two pins, so that you can hold the cam shaft and then wind the tension up, then insert a locking pin. The manual should tell you how to do it - I'm afraid I have never done that particular adjustment, but I think that is how it goes. You have to pull the camshafts out to do it, which it sounds like you will have to anyway.
 

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Discussion Starter · #3 ·
I have the locking pins and know about the special tool.

If I have to wait for my local dealer to get the tool I will be a lot older and have a long grey beard.

I was wondering if it could be done without it. The Haynes says you can, but the explanation is not very clear.

FrankW
 

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Well I'm thinking it should be possible, I don't see why you can't bend a piece of rod to make a U shape that fits into the two appropriate holes, and wind it up using that.

I'm sort of thinking out loud and going off memory of the cams, but something along those lines should work.
 

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IT can be done with a flat screw driver in the gear teeth its a pain but can be done.One thing as a warning dont turn the motor after you take the cams out unless you can find tdc with the alt. marks.You dont need to pull the alt cover if you get the marks lined up right on the cams and dont turn the motor over.
 

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There is no real "winding up" to be done.
All you're doing is tensioning the spring (a glorified circlip type thing) which sits between the backlash-gear and the drive wheel.
This only moves a max of about the pitch of one tooth.

The two holes which line up are of two differing diameters.
Any home-made tool which which is roughly the dia of the bigger hole,
and ground down at the end to the dia of the smaller hole will do.

Just push this in to align the holes, which in turn aligns the teeth, and the jobs done!

Good luck!!

(NB..... I cant see from the photos, but the two holes should only be about half a hole out of alignment when the tension is off the spring.
If they are more than this, or nowhere near together, it probably means a previous owner forgot to put the springs (circlip things) back in after having it all apart!)


V.
 

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Discussion Starter · #7 ·

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My wife has her finger on the gear above the hole on the other side.
Frank, if the two holes are misaligned by more than the dia of one hole then there is a problem there I think.

You'll need to remove the camshaft and disassemble it.
All there is is an external circlip and a thin wavy washer holding the backlash gear to the drive gear wheel.
You should see the C-spring in there, in the gap between the wheels.
Fairly easy to see where it locates. A spigot is what pushes against the spring to give the slight pretension.
Either that or maybe you'll find there's nothing in there at all!!
If so, blame the previous owner!!

It wont have done any harm if you've been running without a backlash spring, but it does make for a bit of a rattly engine!

Good luck!!

V.
 

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the ones i have seen if you dont use the pins when you pull the cams the holes will be about closed up.
 

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Oh yea Ventura the 360 motors are alot worst to deal with cause when one valve is closed the other is open .You 270 guys got it easyer there lol.
 

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Discussion Starter · #12 ·
Thanks for all the help and suggestions guys. I got the gears back under tension using a small screwdriver and I made some pins out of old allen keys. Ground them down to the right size they work just fine. Spent 3 hours going around all the local bike dealers getting the right size shims (Local Triumph dealer had none, which is the usual story) which I got finally from the Kawasaki dealer. They charged me A$9 each to exchange them, its a good job I only needed 3. As they say beggars can't be choosers. Started the bike up and it sounds fantastic, instead of like an old lawnmower. No valve noise, no gear noise, it just purrs.:D

Thanks again guys.(Until next time)

FrankW
 
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