turning the engine over with the cams out.

[Matt Lund]

Not meaning to tell anyone their business but any newbies (me included) will benefit from a quick word of advice. If for any reason you need to turn the engine while the cams are out or the head is off pull up on the camchain to keep it taut. If it is slack while the engine is rotated it will bunch up on the crank sprocket and a previous owner has done just this with my 850 engine. this causes carnage inside the engine, i have a shattered guide holder and the mount has sheared off plus a small lug has broken off the upper crankcase slipper blade support. Worse is this numbskull put the top end back on and ran the bike for god knows how long resulting in the camchain acting like a chainsaw on the broken parts and my engine sump plate was full of aluminium shards many stuck to the oil strainer screen. This has given me a huge headache and just found my slipper blade is bent too. Keep an eye out for this and has anyone known this to happen if adjustment of the camchain tension is overlooked or is it just my bad luck that i got a very neglected project bike?

[Big T]

Since the cam chain tensioner is automatic, it takes an neglected or abused engine to get the type of damage you have.

That's a sad PO story

If you were closer, I'd offer the spare motor

[tom203]

Seems like tensioner was installed wrong or frozen so chain slack couldn't be taken up and guides were chewed up by "chainsaw" action. Probably made unpleasant noise- any sign of valves hitting pistons?
The camchain tensioner is so simple, lots of folks seem confused by it.

[Steve]

The camchain tensioner is so simple, lots of folks seem confused by it.

The hardest part of the tensioner is installing it correctly.

It's rather simple, but too many people don't bother to read the last line of the instructions.

Here is my version of the instructions:
1. Rotate the crank slightly, just to ensure the front of the chain is tight and the back has all the slack.
2. Loosen the locknut and setscrew on the tensioner.
3. Rotate the large knob and push plunger all the way in.
4. Tighten the setscrew to hold plunger.
5. Install tensioner to engine.
6. Loosen setscrew to allow plunger to take up slack in chain.
7. Turn setscrew in until it stops.
8. Turn setscrew out 1/4 to 1/2 turn and lock in place with locknut.

Too many times, the tensioner will be installed with the setscrew rammed all the way in and locked in place,
which does not allow the plunger to move as necessary to take up any slack.

.

[Nessism]

You can turn over the engine without the cams installed as long as the cam chain is held up. In fact, you can turn over the engine by pulling up on the chain itself. I always to this before installing the cams to make sure the rings are properly seated in their grooves and not binding.

[Matt Lund]

Thanks for the replies. No sign of a valve-piston liason but the pistons need a thourough decoke to get rid of the layer of burnt silicone the previous idiot had covered the head gasket in which has added a warped head to my list, it's at the machine shop having a skim. Ever feel you're playing against a stacked deck? When my mate said he had an ideal project bike to keep my mind occupied after we lost our baby boy i had no idea jusy how much it would keep me occupied! £71 for a new slipper blade! Am i right in assuming the 750 blade is the same as the 850?
Cheers