97-yz125 Crankshaft

Uchytil

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Jun 29, 2003
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#1
Are the plastic horseshoe shaped pieces on the crank replaceable, what are they there for, and why do you suppose one side melted in two small palces? The bottom seized but not the bearing, the plastis piece on the right side broke off on the ends and jammed up the lower end. The cylinder had just been replated at Eric Gorrs and the engine had about 4 hours on it. The lower end had not been done and it was due anyway. I want to rebuilfdthe crank rather than replace it. Any yamaha experts out there? Thanks in advance. P.S. If you are parting out a 97 YZ let me know. My email is JCANDE5@AOL.COM
 

marcusgunby

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Jan 9, 2000
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#2
This is a common problem on the older YZs- when eric does the full engine , he works on the plastic parts to make more room for oil to get to the big end bearing.They tend to melt and run into the crank-its just something they do.