Ouch - catastrophic damage - please help

3 replies to this topic
  • Gmo426

Posted October 12, 2005 - 01:03 AM


Hello Everyone,
A sad story to report - Was riding in a remote riverbed Saturday afternoon in Grand Junction, CO when BA-BANG! A noise the likes of which I've never heard B4 and never wish to hear again. I shut her down immediately and discovered a crack and a BB sized hole in my right outer case, and a bottom end siezure.
Took the engine apart tonight - discovered the gear on the clutch basket basically exploded and caused damage to the primary gear. Worse than that it broke off the nipple in the right inner case that holds the dowel for the external shift mech torsion spring.
So I need information please - can that cast aluminum be welded? (it's a clean snap, good welding potential)
Secondly, is there alot of tension on that torsion spring? will a weld be strong enough??
And thirdly, incase, if I do need a new case - do I have to order "Matched Cases" or can I just get the right side and make a good gasket seal?
Thanks for any/all input in this time of need -
And don't worry - my 426 will thump again - harder and stronger than ever!!

  • Daz_426_02

Posted October 12, 2005 - 04:04 AM


I would look on ebay as there are alot of engine parts and it very possible to pick up a good condition case.

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  • MXKyle

Posted October 12, 2005 - 04:12 AM


The cases come as matched sets. I know cause I had to buy a pair myself. You on the other hand shouldn't have much trouble getting yours fixed by welding. It's kind of porous but will still weld satisfactorily.

As far as the tension on the spring post? I once broke off that post on a Honda Ellsinore when I was a kid. I couldn’t get it welded and couldn’t afford new cases so I drilled through and put a countersunk flathead screw in place of the post. It worked great and never gave me any problems and it never broke for the guy I sold the bike to either. I wouldn’t do that these days but it showed that there wasn’t really that much spring tension or the screw wouldn’t have worked.

Good luck,

  • grayracer513

Posted October 12, 2005 - 07:14 AM


I agree. That should be something that a competent welder/machinist ca repair effectively. Provide him the dowel and the shifter, along with photos of what it's supposed to look like if he's not familiar with it.

If you can't find anyone in your neighborhood to trust, there's ED Co.

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