New cam chain fitted is very tight

[kendo57]

First i should say hello as its my first post,
I am refreshing a CB550F2 engine as part of a project i picked up a few months ago.
I have split the cases, fitted a new cam chain, piston rings ect and checked everything over.
Now everything was going well untill a fitted the camshaft, i put the camchain over the sprocket
timed up the cam and then tried to put the sprocket on the cam. I could not get it on by hand
but had to use a screwdriver to slightly lever the sprocket up and slip it onto to cam.
This leaves the cam chain very tight even with the tensioner backed of.

I have checked the cam chain [DID 219T 88 link]  the front guide is in correct with the 'up' pointing
up and the tensioner is fully backed off.
I am at a loss now,  i can only think the head/base gaskets could be too thick [unlikely] .

I could leave it and run the engine for a short while then strip it to see if the chain has bed in and stretched a little but i am a bit woried about.
The gasket set i used was a NP aftermarket set .
Any ideas of something silly a may be missing

T

[Bryanj]

They are tight when new, if you got it onto the cam then it has to be right as with anything fitted wrong it simply won't fit!!

[z1100r]

What I always do is poke long thin screwdriver down and push the tensioner right back and lock it up with its lock nut. Ie tensioner fully compressed. It should fall on then. I can easily take sprocket on and off to move round a couple of teeth to get the timing right then.

[Yoshi823]

Is the front/fixed tensioner around the right way? I seem to remember it has to go in back to front otherwise the cam chain is too tight.

[kendo57]

I have manually pushed the tensioner back with a long screwdriver and locked it fully back.
The front guide is running on the inside of the chain with the 'up' stamp at the top as it looks
in the parts manual.
When i lift the sprocket with the chain attatched it gets a fraction short of sliding onto the cam so i need to put a screwdriver through the sprocket and lever it up at the same time push it onto the cam.
The chain is then under tension even with the tensioner fully back.
I am worried this will put a strain on the chain and cam bearings, although i think the chain will stretch slightly when first run and also expand a little when hot.

[mickwinf]

hi, i too had this problem, and spent many days trying to solve it, in the end i did what you did and levered it on with a screwdriver! Once fitted it now seems to run fine, so hopefully yours will be ok (mine had to come off as the previous owner had set the valve timing wrong resulting in a bent valve, see my thread 3 cyl 550 )Good luck with your rebuild, regards,Mick

[kendo57]

Hi, thanks Mick , its good to hear i am not the only one with a tight fitting chain.
I will leave it as is and check it after its first run. Maybe a while as have lots to do on the rest
of the bike.