HEADS UP!!!

Site upgrade in progress... Core site functions are working, but some non-critical features/functions will be temporarily unavailable while we work to restore them over the next couple of weeks.

Please post any bugs you encounter, but before you do, check to see if it's already listed.

Thanks for your patience while we work to improve the community.

Sign in to follow this  
Followers 0
Gerry B

changing timing chain

9 posts in this topic

Hello,

I'm getting ready to change my timing chain. It's slapping around in there pretty loudly so I guess it's time to change it out.

I am going to attempt to do it myself. The service manual doesn't show you how to do it exactly but it doesn't seem like it would be that hard. I figure I just remove the cams on top and remove the bottom side cover and stator. Is there anything else I'm missing? Any suggesstions would be greatly appreciated. Thanks!

Share this post


Link to post
Share on other sites

You'll need a flywheel puller ($10), but you've been wanting one anyway, and it fits almost everything.

You can try just removing the exhaust cam; sometimes you'll be able to lift the chain around the intake without removing it.

You will need to unbolt the lower end of the cam chain tensioner shoe, behind the stator, as well.

Be careful that a "loop" or hanging link doesn't happen at the crank sprocket before you bolt the tensioner back on. The tensioner should prevent one from occurring after that.

Easy job. :naughty:

But: Retorque the cam caps properly...Very Important!

Share this post


Link to post
Share on other sites

Having just done this 2 nights ago I can verify Grayracer's comments. As he said, be carefull when looping the cam chain on the crank so that a link doesn't get hung up the rear guide bracket. You'll find it's a little difficult to move the front guide enough to get the cam chain past it but if you use a large flat blade screwdriver it can be done (at least it worked for me). If you can not get the chain past the guides you'll have to pull the head off in order to remove the front guide and that's not fun cause you'll have to pull the carb and airbox snorkle and I found that to be the most difficult of my whole rebuild. :naughty:

Be sure you back out the cam chain tensioner prior to pulling the cams out. I don't think it's real clear in the manual but just take a small blade flat screwdriver and turn the tensioner (don't remember which direction) until you feel it click and it'll stay in the retracted position. If that doesn't work then just pull the tensioner off by removing the two bolts.

Good luck.

Share this post


Link to post
Share on other sites

How do you get the flywheel off? Do I need to buy the yamaha flywheel puller or is there any other types of pullers I can use instead? Also, what other special tools will I need?

Share this post


Link to post
Share on other sites

I had a 3 jaw puller that I got from either an auto parts store or somewhere and it worked fine. You might check Sears, they've got a few that would work or you can get one from Harbor Freight and have it delivered to your door. Here is an example of the one I used.

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=45977

There is a little lip on the flywheel that the jaws can grab onto.

On second thought, stay away from Sears. :naughty:

http://www.sears.com/sr/javasr/product.do?vertical=TOOL&pid=00946906000&bidsite=&BV_UseBVCookie=Yes

Share this post


Link to post
Share on other sites
I had a 3 jaw puller ....
OMG... :naughty:

Never use a jaw type puller on your flywheel. You might get away with it, but you also just as easily might not. The flywheel was not intended or designed to bear such a load at its edge, and you can distort the flywheel without knowing it, or break it altogether. If it's distorted, you may take out you stator or worse by trying to run it. I have replaced a number of different flywheels where this was done.

The tool that was designed to be used fits nearly every Japanese MC made except a WR, and can be had at any shop you walk into for about $10. Why the hell would you use anything else when the right one is so cheap and works so well?

Share this post


Link to post
Share on other sites
OMG... :naughty:

The tool that was designed to be used fits nearly every Japanese MC made except a WR, and can be had at any shop you walk into for about $10. Why the hell would you use anything else when the right one is so cheap and works so well?

Cause I had one and it was handy and I guess I didn't know any better. Since you say you've replaced some that have been damage I went out and popped it off again and chucked it up in the lath to check the runout. Everything is within a few thou, so I guess in this case no harm no foul. I must have gotten lucky.

I don't know what "shop" you're talking about where you can just walk right in and buy a flywheel puller for $10, but there's not a bike shop around here that carries one. It would have just been another week down the drain.

Share this post


Link to post
Share on other sites

Could be just a matter of a lack of demand for them. But, since you're up the mechanical scale far enough to understand a lathe, you can see why it would work better to pull against the solid steel center, close to the taper itself, than to place that strain on the much lighter stamped steel or aluminum shell of the flywheel.

Order yourself one, and see if it doesn't work better. Once your friends find out you have one, you'll become even more popular than you already are. :naughty: Like I said, it fits 95% of everything Japanese that has an ignition flywheel back into the late 60's.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0