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broken bolt


cem

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Hi everyone. While I was installing a remax bellypan I broke the bolt seen in the picture? How long can I ride before I get the bolt out and install a new one?
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18839088_10155349639763996_3426366278328021993_n.jpg
 

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No way of telling may do 100,000 miles or down to the end of your drive,
those bolts hold the crankcases together and it's force from them that
clamp the main bearings among others may be a real pain to get the broken bits out.

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I just have to make 50 miles or so until Monday. Then I will take it to a repair shop. If the engine does not break until then, I am totally fine with it. :-)

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ducttapewd40

If you really have to drive it you might want to put the remainder of the bolt back in and only gently tighten it down. Two or three threads will probably be better than nothing, but I'd still be safe and trailer it.

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If it aint leaking it wont harm it PERIOD. it is going to be a pain in the royal arse to get a drill centered and an easy out in there. As long as it is not seeping any oil you should be fine, however that said, get it fixed asap.

“Laws that forbid the carrying of arms disarm only those who are neither inclined nor determined to commit crimes.” --Thomas Jefferson quoting Cesare Beccaria

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Chances are the remaining threads are still connecting the two parts as well. Although not at full torque, obviously, but better than nothing.
 
It should not have snapped, of course, especially since these are pretty new bikes. But also why using a rattle gun is a good idea on stuck bolts - it's rare to snap anything with a rattle gun set to a reasonable level of torque.

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did it break while removing it or did you over torque it retightening?
 
If it broke while retightening, and assuming the end of the bolt is not bottomed into the case, there might be little to nothing holding the end that's still yup there. If yer really lucky, you might be able to put a screw driver up there, catch an edge, and just unscrew the stub.

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it broke while removing. I assume the rest is still holding the two blocks.
Only the upper case will be threaded - otherwise, the bolt head will never be able to pull the 2 case halves together.  
That bolt was likely faulty or maybe overtightened at the factory and strained.
 
Doesn't look like there's any thread locker on the threads showing. If that's true all the way up, I'm still gonna suggest there's now nothing holding it but the friction from the threads. Spray some PBlaster or whatever penetrant up there and let it soak in. Then reach up with a flat blade screw driver and see if it'll move.
 
got nothing to lose by trying. 
 
 
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given the proximity and the number of bolts placed nearby, this one can probably go unfixed for the remaining life of the bike. Very disappointing that it managed to snap off. I would echo the previous sentiment about threading it back in and letting the remaining 3 threads apply some clamping force. You may need to shim the bolt slightly (thin 6mm? copper washer). If that's a 6mm bolt it's IMO an inexcusable cockup by Yamaha Engine department. Cam covers, sure but not crank cases. The bolt is also IMO bordering on too long for  6mm application. I'm also guessing that occlusions aside, I suspect someone forgot their first year materials class' discussion about galling.
 
The shop manual says 17ft/lb and to lube with engine oil. I'm going to guess it was installed without lube and/or was over-torqued.

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it broke while removing. I assume the rest is still holding the two blocks.
Only the upper case will be threaded - otherwise, the bolt head will never be able to pull the 2 case halves together.  
 
 

You are of course absolutely correct, sir - excuse my previous brain fart  (zzz)
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You have a heck of a lot of corrision on that motor? How are you washing it or maintaining it? are you using a water dispersal or is the bike in a wet humid climate? That bolt may have snapped for other reasons.

“Laws that forbid the carrying of arms disarm only those who are neither inclined nor determined to commit crimes.” --Thomas Jefferson quoting Cesare Beccaria

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The 07's seem to be covered in incorrectly torqued bolts. Think yamaha is useing the new laissez faire approach to engine construction assembly. Too tight and too loose. Mine had a stripped engine bolt from the dealer ( I always check the whole bike when I get them home.)

Go forth and modify my son...go forth and modify...

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