CAM Chain Problems

[estagor]

I was riding my GS750E 1981 (54,000km) the other night and then all of a sudden as I was geering up I felt the engine drop power and feel something give way in the engine.. I got the bike off the road as I lost power and it would not start...lots of juice not nothing turning. I have the valve cover off and the ignition coils out of the way and looking down the engine, the cam chain is off and bent as far as I can see.... So dumb question but am I looking at taking the engine appart to fix this latest challenge?

[Steve]

Yes.

.

[Nessism]

The chain can be changed by breaking a link, hooking old chain up to new chain, and then threading the new chain through. Once it's around the crank, you need a rivet tool to peen over the joining link. Of course, this assumes the chain is the only thing that's wrong...and that's unlikely. Only thing I can suggest is for you to check out the tensioner shoes, and all the other parts are carefully as possible before going after the chain.

[67fire]

Don't forget to look for bent valves.

Eric

[estagor]

Thanks for the feedback guys I think the best thing to do is start taking the engine appart...I don't want to risk a quick fix then end up going through it all over again...

[flyingace]

The chain can be changed by breaking a link, hooking old chain up to new chain, and then threading the new chain through. Once it's around the crank, you need a rivet tool to peen over the joining link. Of course, this assumes the chain is the only thing that's wrong...and that's unlikely. Only thing I can suggest is for you to check out the tensioner shoes, and all the other parts are carefully as possible before going after the chain.

I would follow this procedure before I took the engine apart. You can always take it apart, but you may find replacing the chain and some tensioner components is all you need to do.
To me, taking an engine apart is time consuming and expensive and should be last resort, not the first. Just IMO.

[Kerry]

Nice to see other GSers in the National Capital Region! I don't know how many are on the GSR forums, but I do see a few GS's around here (Aylmer). Keep an eye out for me and The Flame!

[rcp]

I'm in Ottawa and have a chain tool and some used parts, including cam chain and valves (not sure if 1000 sizes are the same). Sending PM with contact details.

- Richard

[estagor]

Thanks Richard.. I'm in Orleans my email is estagor@rogers.com 613-824-8618 home or cell 613-795-8618... I would have to check if the parts would work...

Update!!!
I have pulled the engine appart it looked bad so it was best thing to do as the crankshaft would not move to get the chain out... it's my first time doing this so my cherry has been popped.. The chain is broken in two spots and the second part is jammed at the bottom of the crankcase.. which will not move in either direction...any suggestions? Do I have to take the engine out of the bike to remove the crankshaft so I can free up the rest of the chain.. I had one valve that is questionable.. and the pistons seem ok but I will post a picture for comments... my compression was low 120 or so...but I will take measurements to see if I need to do more....

Any thoughts on the removing the rest of the chain would be appreciated...

Ottawa GS riders we need to get on an email list so we can have weekend rides up in Calabogie!!!!

[blowerbike]

food for thought.
atleast in the states the 80-82 GS750 engines are cheap to buy.
sometimes you can buy a parts bike for about the same money as an engine.
good luck with your project.

[Big T]

Yes, you need to pull the motor out and split the cases to get the cranks out

You'll have to assess whether it's better to repair or replace the motor from there

You may be lucky and just need a new chain and guides along with some valve lapping and fresh valve stem seals

54,000km is a relatively low mile motor. It should have gone twice that far before needing that level of work

Pictures,please

[estagor]

Here is a look down in the crankcase where the chain is broken I have a limit of one photo so I will be uploading the valve pictures when I can

[estagor]

Under side of the valve

[estagor]

other set....

[estagor]

Top side of valves where the other bite of damage I can see