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Cylinder Is Off And The Piston Is Free! Whats Next?

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  • Author
You just have to turn things upside down, like bars and rear support tripod!

Agree the top looks very usable!

You see, if the bottom roller balls have siezed due to water, this will certainly pit and score them. After that, it is just a matter of time usually, as they will beat themselves to death on the pitting like a cobbstone! The time only depends upon the severity and the stress imposed thereafter! And it varies. :thumbup:

And that, of course, means splitting the crankcase?? Which would mean removing the motor?? So I should just do that to start with. . . no?

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Just an idea but remove the left hand cover to reveal the flywheel and try and move the crank by turning the flywheel, next I would drain the gearbox oil and remove the clutch cover and have a look at the gear on the end of the crank and then try and turn the flywheel checking how it mesh with the clutch gear,if the gear is removed from the end of the crank then there should be nothing to stop it turning if the crank is not seized.

Obviously protect the crank since the piston is off so it doesn't bang into the engine case.

  • Author

So I finally got the flywheel cover off!! I had to drill the screw heads off! (why would they use a screw and not a bolt?? :thumbup:) And there is NO rust ANYWHERE to be seen. BUT!! But it is all white?? Is it suppose to be white? I can turn it though, not a bit. What I can say, is there is VERY little free play on the crank and the flywheel. So thats a good sign??

So I finally got the flywheel cover off!! I had to drill the screw heads off! (why would they use a screw and not a bolt?? :thumbup:) And there is NO rust ANYWHERE to be seen. BUT!! But it is all white?? Is it suppose to be white? I can turn it though, not a bit. What I can say, is there is VERY little free play on the crank and the flywheel. So thats a good sign??

The white is either mould or aluminium corrosion product and both are quite normal for a bike that has been stored damp. The white stuff is the least of your problems. Can you clarify what you mean by "I can turn it though, not a bit"?

Edited by feetupfun

So I finally got the flywheel cover off!! I had to drill the screw heads off! (why would they use a screw and not a bolt??

So you don't have to carry a socket set in your backpack to get the cover off if you need to while out riding

  • Author
The white is either mould or aluminium corrosion product and both are quite normal for a bike that has been stored damp. The white stuff is the least of your problems. Can you clarify what you mean by "I can turn it though, not a bit"?

Sorry, i meant to type "I cant turn it, not a bit" There is a very small amount of play, like less than a 1000th or so

Edited by trialsnewby

You next step is to work out why you can't turn the crankshaft.

As Andy.T said, drain the gearbox oil and take off the primary drive/clutch cover so you can take the gear off the end of the crankshaft and see if the problem is with the crankshaft bearings or with something else.

  • Author
You next step is to work out why you can't turn the crankshaft.

As Andy.T said, drain the gearbox oil and take off the primary drive/clutch cover so you can take the gear off the end of the crankshaft and see if the problem is with the crankshaft bearings or with something else.

So when I take off the cover and remove the gear from the crankshaft, what am I looking for?? How will I decide if its a pronlem with the bearings or with something else??? Or is just kind of a wait and see thing?

I'll just do it and take pics. . .

Edited by trialsnewby

Now when you come to take the clutch cover off, that too will most likely have phillips screws which can either burr or snap off. You can use an impact wrench to loosen them or using a phillips of the correct size, with a vice grip attached to the shaft of the screwdriver, ONE firm tap with the Hide Hammer on the end of the driver, then a sharp tap on the vice grip while maintaining inward force on the driver. When you rebuild I would use allen bolts.

Tony

If the engine wont turn with the gear removed then the bearings are seized, if it does turn then the problem could be further in the engine, perhaps the gearbox.

Get an impact wrench if you can, every tool box should have one. And remember to take the slack out before you hit it, works much better.

  • Author
Get an impact wrench if you can, every tool box should have one. And remember to take the slack out before you hit it, works much better.

Sorry if this sounds stupid, but take the slack out of what?

I think what B40RT is trying to tell you is to compress the inpact wrench with a twist of the body so that when you hit it this wil remove some of the bounce that you get with this type of wrench, if your goiing to use one on the crank gear then there could be some slack between the gears that you could remove also by a slight twist of the gear. if the crank is siezed as you mention then the nut on the end of the gear will come off with a socket and wrench.

  • Author
I think what B40RT is trying to tell you is to compress the inpact wrench with a twist of the body so that when you hit it this wil remove some of the bounce that you get with this type of wrench, if your goiing to use one on the crank gear then there could be some slack between the gears that you could remove also by a slight twist of the gear. if the crank is siezed as you mention then the nut on the end of the gear will come off with a socket and wrench.

AHHHH. . . I get it!! Thank you. Good advice, I wouldn't have done that.

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