Cam bolt removal - help please

[monkeyboy]

I'm biting the bullet and removing the head on my GSA to investigate the loose cam chain. This will means I have to take the exhaust off, which means the cheese bolts on both exhaust connections will break, which means I'll have to remove BOTH heads and get the buggered studs out and replaced

Anyway - problem No.1 is I can't get the bolt off the end of the cam - ie the timing chain sprocket. The engine turns and I can't lock it. I've tried using the 16mm on the front of the engine to pull against but unfortunately IT comes undone rather than the cam bolt.

What's the best way of doing this please? The manuals obviously assume the engine is out and locked at the flywheel.

Thanks

 

[iftikartaxis]

bolt

have you tried putting the bike in gear usually works

 

[ChrisH Kerry]

According to Haynes you can "put a steel rod at least 100mm long into the hole in clutch housing on left hand side of engine. There are corresponding holes in flywheel and the rear of the crankcase. locate the rod through all holes, thereby locking flywheel and hence engine"
Never done it but that what it says...

 

[monkeyboy]

I did put it in gear and got the wife to stand on the rear brake but all the cam gear was loose at the time and it didn't look happy. I'll pop all the bolts on and try again - next weekend

As for the rod trick - didn't know that one. Where are the crankcase holes though? Not where you can see the flywheel I would guess. That would sound like a good scheme if I can locate the holes

ta

 

[helitrooper]

Take off the plastic cover which is over the starter motor, left side near foot peg, it has the electrical socket on it, you will see the hole where you have to put the locking pin, I used a coach bolt about 4 or 5 inches long, I ground off the thread and made it fit, engine needs to be at TDC. Once you have loosened the nut on the cam a little, cable tie the chain to the cog wheel so that you dont mess up the timing.

 

[monkeyboy]

Take off the plastic cover which is over the starter motor, left side near foot peg, it has the electrical socket on it, you will see the hole where you have to put the locking pin, I used a coach bolt about 4 or 5 inches long, I ground off the thread and made it fit, engine needs to be at TDC. Once you have loosened the nut on the cam a little, cable tie the chain to the cog wheel so that you dont mess up the timing.

Excellent - thanks for that. Any rough idea of the diameter? Coach bolt so maybe 10mm? I'll get it off and take a look in the week.

Thanks again

 

[helitrooper]

have a look here

http://users.rcn.com/dehager/

the third line is the one you want

 

[MattW]

In gear, stand on the brake pedal and a longish socket wrench. You can do it on your own with a bit of thought abut how you position yourself and the tool. It's a high torque fastener so it needs a bit of leaning on - it usually let's go with a heart stopping crack

Don't be tempted to use an impact wrench / rattle gun - I've read of people shattering the cam chain tensioner blades with one...

 

[Ady00]

These bolts are put in with thread lock so get a blow torch on the head of the bolt only and when a dab of spit sizzles on it thats hot enuff this makes it alot easier to remove...thats the advice I was given when I changed my cams and it needed nothing more than putting in gear and using the back break....job done....Ady

 

[Ady00]

Oh and cable tie the sprocket to the chain that way you will keep it all timed up correctly......Ady

 

[monkeyboy]

I found the lock hole, inserted a long M6 and the cam bolt came undone fine.

So I'm on to the next problem

The left side is rattling very badly and it certainly sounds like chain noise to me. I've recently replaced the tensioner with a brand new one - one of the upgrade ones with the captive tensioner instead of the separate spring and shim arrangement. The noise only seems to have got worse since I changed the tensioner. I've got the valve gear off and can see properly down the timing chain void. I want to avoid having to remove the head and bore if I possibly can obviously! I can see both the top and bottom chain guides and they are both in one piece and complete so it's not a snapped guide.

So - could I possibly have been give the wrong tensioner, or do the chains stretch? Or...what else could it be that is causing the chain to run slack? The valve gear is all nice and tight. When I opened the cam chain inspection hole after stopping the engine, the chain did seem to just be dropping off the cog at the bottom and look alarmingly slack.

Obviously, on the left, the 'pull' is from the bottom and on the right it is from the top which is why the tensioners are where they are but the fact it looked so slack on the 'bottom' on the left seems weird - like the tension just wasn't being kept up on the top.

The new tensioner has a much reduced range of operation but is a lot stiffer, even though it is shorter than the old one at rest.

I dunno - I might just have to put it all back together and take it to an expert cos I just can't see anything obviously wrong or broken

 

[slaphead GSER]

This sounds exactly like mine, I have recently taken the L/H head and barrel of and found everything as good as new. Now we are thinking perhaps low oil pressure causing the tensioner to not work the way it should. Mine is 03 twin spark with 60,000 miles !