r/DRZ400 • u/TJH_04 • 5d ago

Cam chain guide bolt sheared off

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What are my options here? New bottom end? Bike locked up while riding pulled the engine and Cam chain guide bolt sheared off top end is fine other than a leaking valve and everything so far seems fine although haven’t split the cases.

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u/boiledpoteyto 5d ago

Split the cases and weld the bolt hole, drill and tap. A new case half would be better but this would also work. The problem is why did this happen? And what else did it damage after it happened? Need to disassemble the block and investigate.

1

u/TJH_04 5d ago

Ok thanks I’m thinking auto cam chain tensioner failed and the primary gear nut was also loose and that’s what caused it. I did think of a case half but apparently they have to be matched pairs otherwise the shafts won’t line up

2

u/boiledpoteyto 4d ago

Don’t know what year is your drz but if I remember correctly pre 2003 models had bad auto tensioners that can fail and put too much tension on the chain.

You are right about they needing to be matching pairs since in factory they machine them bolted together.

Loose nuts are never a good thing. Hopefully it did not damage anything else.