Honda CBR 600RR Forum banner

1 - 7 of 7 Posts

·
Registered
Joined
·
311 Posts
Discussion Starter · #1 ·
So here goes:

While reinstalling my stator cover after painting it I was installing the four allen bolts that hold the stator to the cover. Well I was torquing them to spec (10 lbf-ft) and one just kept on turning. After a few turns I figured the threads were stripped and I removed it to find out that it had been stretching! I guess maybe because there was oil on the threads or I was turning too hard, even though I was using a torque wrench..

But anyway, one of them stretched a little bit. I reinstalled all four and was able to get the streched one pretty tight, but is this safe?

Am I ok leaving the stretched bolt in there or is there a bigger chance of it loosening up and falling out, or just breaking from the vibration and falling into the crank?

Also, when reinstalling the wire cover I accidentally used a painted bolt from the exterior of the biik instead of the proper one that was originally in there. It was clean though, so I think I should be ok.

Can anyone let me know if that bolt should be ok or should I just buy new ones and take the whole thing apart again and put the new one in? Thanks
 

·
Registered
Joined
·
836 Posts
u should replace that bolt....if its "stretching" that means the bolts weakened! prob do to heating. oild wouldnt cause that...also when u were torquing it, did it ever reach the required torque then u kept going cause it kept moving? cause if so force is what stretched the bolt. FYI if you are torguing something and u reach the final torque...STOP! if its still turns thats fine...the only time i would worry bout torque if i reach my final torque and a fastener continuted to move, is if i were torguing a nut to a stud...cause that could possibly mean stud rotation, which is bad...anyhow, change out the damaged bolt and you should be good!
Cheers,
Flent
 

·
Registered
Joined
·
311 Posts
Discussion Starter · #3 ·
I didn't reach the torque I wanted, so no I didn't keep turning after the point.

Also, it stretched due to force. It stretched BECAUSE I kept turning, even though it never reached the torque. I really want to ride tomorrow and won't have the bolt for a few days at least. I think it should be ok as long as I change it relatively soon.

The reason I think it should be ok for a little while is stretching happens at plastic deformation, or when the yield stress of the material is reached. The only way to stretch it more is to apply the same stress. Once plastic deformation is reached the yield stress of the material doesn't change, it just doesn't bounce back to the original shape (that would be elastic deformation). But once you bring a material past the yield stress it becomes harder, but also more brittle. I don't want it to crack off in there, because that would be very very bad. I'm going to buy a new bolt, but I really want to ride at least for a little bit before I can get it, unless the dealer has it in stock and then I'll go tomorrow and get it.
 

·
Registered
Joined
·
836 Posts
im sorry, i misspoke...what i meant to say was galling...not "Force" i.e. something blocking movement across the threads, causing excess friction, causing heat to build up, therefore causing your bolt to deform in a plastic manner.

ok so u know a lil bout plastic deformation! but that means u know that now that u have succeeded at stretching (plastically deforming), u have also succeeded at weakening the bolt. and while u will not be turning it anymore, that doesn't mean the force stops...its for the most part of a motorcycle engine! meaning every second you run the engine vibrational force acts on the bolt. and depending on how close u got it to its tensile strength limit, your only moves closer to its brittle fracture limit and will snap if left unchecked! not saying its gonna dislodge and cause damage to your stator winding...but the next time u have to take it out it may snap and u get a whole other headache trying to get the left over bolt out of its female end! and i happen to know that is a headache that u don't want. I've had to extract sheared bolts out of tons of things, and couldn't imagine doing it with something on my bike!
 

·
Registered
Joined
·
311 Posts
Discussion Starter · #5 · (Edited)
Yeah....looks like I'll be getting a new one before I start it up. Right now it is already put back on and tightened, but I won't start it.

I just don't get why it kept on turning without getting tight. Oh well, **** happens.

I also already filled the bike with oil. If I just lean it over on its side do you think I'll be able to take the cover off without spilling oil everywhere? And how far on its side will be enough? Thanks for the help

Edit: What if I were just to run with the three of them until I got a new one?
 

·
Registered
Joined
·
2,120 Posts
No need to tip the bike if you have a stand. The oil level will be below that stator cover. And If you HAVE to ride, I would go with 3 bolts cause I wouldn't want the bad on to break and end up in the motor somewhere you don't want to find it.
 
1 - 7 of 7 Posts
Top