Valve Timing Question gs450

[friedshrooms]

I was wondering how I time my 1981 Suzuki GS 450. I tore apart the top end because the exhaust bolts broke off in the head, got the head machined, cylinder media blasted, and all new gaskets. After all that I do not know how to time it so any information would be appreciated. A picture of the magneto side is provided because I did not see a TD TF mark on the timing advance, and I don't see one here... Also I have a GS 550 manual and was wondering if I could use that as a reference for the timing chain connecting to the valves? Theres a diagram in the book I could probably understand if it's worth it.

 

[Nessism]

The timing marks are under the signal generators on the other side of the engine. Align the 1-4 T mark, set the 1-- mark level with the cam cover surface, and then count the pins between the 2 and 3 mark (only I don't know how many pins to count - 18 maybe). Please find a manual or search the archives since I'm sure it's there.

 

[Mekanix]

On the right side of the motor pull the timing cover off. ( thats the little one with 3 bolts)

Look through one of the holes and you will see L, R, F, T....

you want to turn the crank until you see the R and then just a little more until you align up the T mark with the line near the top left screw.


Then set the cam's so that the two notches point towards eachother.

release the tensioner and rotate it to see if they stayed where they were supposed to or try again until they do.

If it ever binds, even slightly, Stop, and backup. NEVER use the starter to crank it for this stuff,

a plain wrench is best because when the cam's move they sometime make the crank jump a bit , So no rachet either.


You can download the manual for the 400-450's from Basscliff's site


http://members.dslextreme.com/users/bikecliff/


And probably end up spending the next couple of hours going through all the stuff on there

Good luck

 

[Charlie G]

If you haven't figured it out yet check my thread "Lost a nut!". I'm working through it now.

cg

 

[friedshrooms]

Yeah I figured it out with my GS 550 manual and its running okay now. Thank you for the advice, I did use a wrench and take my time. If I touched that starter it would have likely destroyed something because the timing chain kept jamming up. Though I am curious would my local motorcycle shop have shims? Or would I have to figure out what specific shims I need and order them from Suzuki?

 

[spwalker09]

ask your local shop if they have shims. Mine did. Otherwise order from Z1 Enterprises or a similar site. I remember Z1 being one of the cheaper ones.

To figure out what shims you need, take a feeler gauge and determine your clearance to see which valves need re-shimming. On the ones that don't meet spec (under .03mm or over .08mm) take a look at the marking on the shim...that's the size. They may be on the bottom, so you might have to take the shim out. For valves under clearance (.03 or under) go down a size (they run in .05mm increments). For over clearance go up a size, but if you're at around .08, I'd probably stay there to avoid having too little clearance.

 

[Steve]

Though I am curious would my local motorcycle shop have shims? Or would I have to figure out what specific shims I need and order them from Suzuki?

Order them from Suzuki if you have lots of money. :-\\\

New shims are in the $12-15 range. New shims from Z1 are $5.28.

However, check with your dealer's service department. Sometimes they will swap shims with you for a modest fee. I have heard of some even doing it for free. :clap:

You can guess what shims you will need, but I offer a tool in the form of a spreadsheet that will help you determine what you need. Look at the end of my sig for information.

.