Sport Bikes banner

1 - 11 of 11 Posts

·
Registered
Joined
·
526 Posts
Discussion Starter #1
So as you all know I was having trouble with the bike accelerating through midrange. Well today I decided to pull off the head cover just for the heck of it. While I was at it I followed the service information to check the timing chain. To my suprise when I checked it against the manual's specs and discovered that my intake cam shaft was 16 Pins from the front sprocket. The service manual says it should only be 15 pins apart to line up the marker. I have made up a drawing that I have attached. What symptoms would this cause? What harm could this have done? Am I missing something? Should I look at it again before adjusting the intake cam one tooth. I am suprised at this because I just had the bike in for a valve adjustment. Could it have been like this since the previous owner put a manual cam chain tensioner on it? How did it even run like it did if the cam was off?

Please help
 

Attachments

·
Registered
Joined
·
25 Posts
Well, it looks like your shop that did the valve adjustment put it together wrong.... They most likely had the cams out of the bike while they were replacing the shims and didn't assemble it properly while going back together. I'd bring it back there and tell them what you found.
 

·
Knuckle Dragger
Joined
·
187 Posts
To answer your other questions....relax...no damage done by being a pin off. Just a little out-of-spec valve timing. If you're so inclined, remove the cam chain tensioner, unbolt the offending cam, rotate it to the correct position and button it back up. (careful when torqing down the cam bearing caps....both bolts at the same time).

If however, the shop did it...let the shop fix it.
 

·
Registered
Joined
·
526 Posts
Discussion Starter #5
I will just do it myself. I am another person who can not stand taking something somewhere to have work done to it. I loosened the cam chain and rotated the cam to the correct pin. Should I really need to replace the head cover gasket if it is not damaged? Also will normal gasket sealer work in place of the Suzuki Bond gasket sealer?

-CBC-
 

·
second chimp in space
Joined
·
3,344 Posts
I'm with you. Why send it back to the people who screwed it up in the first place?

Did the crappy running start with the valve adjustment, btw? if it just randomly started maybe the tensioner is on its way out.

the cover gasket should be ok. Clean off any gunk, though. Be careful with the half moons. I've used normal sealer before, though the guy who wrote "the motorcycle performance handbook" (great book) said the yamaha stuff is the best. He made an argument about how it's safer because of the way it behaves when you use too much and it gets in the oil, but i don't remember what it was at this late hour.
 

·
Registered
Joined
·
526 Posts
Discussion Starter #7
Well it has a manual cam chain tensioner to begin with. So I basically followed the manual to get the cams lined back up properly. If you find out what that stuff was called let me know. I found some Permatex head gasket cover sealer at the local Autozone.

It wasn't running as good after I got it back from the shop but it wasn't running terrible enough to take it back. I guess I didn't recognize it off hand.

Right now when I am aligning the chain with the bottom main sprocket and exhaust sprocket the arrow is suppose to be flush with the gasket surface. I can only get it about 1-2mm above the surface at top dead center in the starter clutch window. Is this because the cam chain has stretched somewhat since it was new? It is only just a hair off and I have the intake and exhaust sprockets 15 pins apart on the marked 2 and 3.
 

·
Knuckle Dragger
Joined
·
187 Posts
It sounds like BOTH cams were off. Both cams AND the timing indicator should all line up.
 

·
Registered
Joined
·
526 Posts
Discussion Starter #9 (Edited)
Okay so I will go skip the exhaust cam forward a tooth to see if I can get them spot on with TDC in the pilot hole.

It really makes me wonder how they did the timing when I couldnt even see that the starter cluch and pilot hole were ever taken off. Well back to work... :)

I do know for fact that the head cover was off thought because those allen bolts were worn.

Here are some pics of what I have. Is this as close as it gets?
 

Attachments

·
second chimp in space
Joined
·
3,344 Posts
That looks ok. But install the cam chain tensioner and see if that affects it. It will also change a bit when you torque down the cams.

sorry, the book is a 20 hour flight away right now.. but i'd think it was the only sealer Yamaha made.
 

·
Registered
Joined
·
526 Posts
Discussion Starter #11
Thats the end result. I did not loosen the cams, the chain tensioner has about 1 1/2 inches of threads left on it at the proper chain defelection of 1/4-3/8ths of an inch between the cam sprockets. Cams are 15 pins apart as the manual.
 
1 - 11 of 11 Posts
Top