How do I safely split my 850 engine cases

Ron L

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Go slow, avoid wedging a screwdriver in the seam, make sure you have all bolts and screws removed.

I use a length of wood dowel and a light hammer and tap gently around the circumference and LIGHTLY on the crank until the joint splits. The 850 has roller bearings, so this will not impede the separation.

I personally don't recommend the pullers that Old Britts sell as I am concerned that too much pressure can warp the cases or strip the threads for the primary case.

YMMV
 
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The factory service manual has an illustration showing how to safely drift the cases apart using a piece of wood.

The 850 motor I just did had heavy corrosion on both dowel pins and needed a bit more than "gentle" tapping. It put up a good fight every mm of the way but finally yielded.

Debby
 
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Case splitting

Thanks for the tips--Which factory service manual?? I have the haynes. Where do you get the factory manual??
 
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Re: Case splitting

Mark Cigainero said:
Thanks for the tips--Which factory service manual?? I have the haynes. Where do you get the factory manual??

The one I'm referring to is the manual published by Norton Motorcycles (a subsidiary of NVT Ltd) back in the day. It's been reprinted and new copies are available from any good Norton parts dealer. Definitely worth having in your library.

Debby
 
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