Motor mount bolt grade?

Pankz

Member
Mar 9, 2017
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California
What grade should the motor mount bolts be? Anything special aside from this?

I'm in the middle of a new blaster build, my first build ever. I don't even have the original mount bolts to look at. I see yamaha wants like 10.00 for the upper mount bolt. Is this a grade 10.9 bolt or a 12.9, or neither?
 
Let me try to be clearer with my question in case it wasn't.

I'm looking for the grade of steel for these bolts not size or torque specs. Anyone else chime in here?
 
8.8 grade will be fine as the bolt only needs to be torqued to 45Nm.
A 8.8 grade bolt can go to 49 uncoated or 59 for zinc coated.

Look at the torques the bolts are in the service manual for the engine then buy the grade of bolt that can handle that torque.

Just get some 10.9 and be done.
 
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Perfect, now the light registers! I see what you mean. Yes I do have the manual here, thanks to this forum, and could find the size and torque spec. I simply didn't put it all together!

Thanks so much Mark, you cleared things up perfectly!!
 
the thin motor mount bracket would probably break before the bolt does
i bet you could bend the mount, but probably not the bolt:)
 
the thin motor mount bracket would probably break before the bolt does
i bet you could bend the mount, but probably not the bolt:)
Very true! Your right, and I'm probably over thinking things too much. I just want to be sure this bike is safe when put back together!
 
just buy oem if in question:D
i now it is harder but leaves all doubt behind:)
i think #2 is one of them just search internet ...
easier then a hardware store.
i have never heard of a bolt breaking on a blaster,just pistons/chains/cases lol:)

buy these bolts bf.png
 
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just buy oem if in question:D
i now it is harder but leaves all doubt behind:)
i think #2 is one of them

View attachment 30175
Yea I know right? Ive given Yamaha so much money in the last couple months its unreal though, was trying to save a few pennies hah.

BTW, Partzilla.com has been the absolute cheapest place for me to find OEM parts.

Thanks again for all your help you two.