[Edgar Plascencia]

I can’t tighten my chain to the right specification on my 2003 Honda 400ex, if I try to tighten it my axle bearing carrier won’t let the back axle rotate. I don’t know what to do

 

[SlammedRanger]

Sounds like the bearings in the carrier are either seized or completely destroyed. This is what happens when either of those are the case. Tightening the chain pulls on the axle and puts it in a bind. Show us a few pictures of the axle right where the sprocket hub goes into the carrier.
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