Chappy LB50 crank binds when I put on right crankcase cover

John Lusignan /

So my crank binds when I put on right crankcase cover. is that suypposed to happen? I took the motor aprt last year and it sat for a while. I vaguley remember taking a 2x4 block and a sledge to get the crank out of the right case? Could I have mushroomed the end of the crank? It doesnt want to go into the locator hole (?) in the right crak case cover. When I put calipers on the crank shaft it reads abround 11.00mm at the tip. Just slightly lower it reads 10.95mm. To the eye I don't believe I can see any mushrooming.

I was able to line up the cover and using a criss cross pattern tighten the crankcase cover screws until the cover was flush with the case. I know this is not recommended. When I did this I was unable to move the piston rod in or out. If the crankcase cover is off everything moves freely. The cases are sealed and everything lines up perfectly. I didn't think that the crank was supposed to bind up when that cover was on. Am I wrong?

Is there anything I can use to take a bit of material off the tip of the crankshaft?

I've been using some 400 grit sandpaper but I feel like that hasn't really done anything and I'm not sure if I'm doing the wrong thing.

Any help is appreciated. Thanks in advance.

-John

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Re: Chappy LB50 crank binds when I put on right crankcase cover

take a file to it.

Re: Chappy LB50 crank binds when I put on right crankcase cover

Can you use more then one gasket?

Re: Chappy LB50 crank binds when I put on right crankcase cover

are you using ANY gasket? you absolutely need one for proper clearance.

I can measure the stub of my crankshaft but it might take me a day or two.

Re: Chappy LB50 crank binds when I put on right crankcase cover

> John Lusignan Wrote:

> -------------------------------------------------------

> It doesnt want to go into the locator hole (?) in the right crak

> case cover. When I put calipers on the crank shaft it reads abround

> 11.00mm at the tip. Just slightly lower it reads 10.95mm.

That section of the shaft should be the same diameter , tip to shoulder .

Sand paper or file the tip circumference to conform with the inner measurement .

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