Engine Mounting Bolts

[Vek]

Hi All, Newbie here.
I am in the process of refreshing/rebuilding my TRX which I bought last year as a project. However when putting the engine back into it's freshly powder coated frame I managed to snap the top rear engine mounting bolt . I didn't get anywhere near the torque setting before the thread stretched and then the bolt snapped on the thread.
My question is - Have any of you used stainless steel replacements if so where did you get them from and how much? I can get some OEM replacements from a dealer but was wondering if any of you had used anything better? I intend to replace both the top and bottom rear mounting bolts.
Kev.

[cobbadiggabuddyblooo]

My choice would be an OEM bolt from Yamaha or find one at a wreckers.

[bagmaker]

Stainless would not be the bolt of choice there Vec, it will work harden and snap.
See if you cannot find a plated one from somewhere and double check your torque wrench

[Vek]

Thanks for the advice guys. Guess I'll order the OEM ones from yamaha.

[cobbadiggabuddyblooo]

Follow the torque specs too from the manual.
.. it can be downloaded online from here..

[Vek]

Are they different from those in the Haynes manual?

[cobbadiggabuddyblooo]

No, they should be the same...

[Satoru]

Hi Vek,
A couple of years ago I did tear away the thread on the lower bolt of the rear shock absorber of my TRX, and I was not using really a lot of force.
Just a couple of months ago I did snap the bolt of the rear brake of the CBR (while removing it!) in a way similar to what happened to you: it stretched first (diameter of the thread in the stretched area was 7.30mm vs 7.80mm elsewhere) and then snapped.

In the latter case I did a mistake I will avoid in the future: I did not use Svitol before force application.

I discussed with a friend that is into metalworking and in his opinion the bolt had the risk of snapping during normal use anyway.
He's kind of an extremist: in his opinion after so many years (20)and miles (50k+) nuts and bolts should all be replaced with new ones for safety reasons because we don't see with the eye the metal fatigue, but is there nonetheless.