Houston we have a problem! Red Locktite...I mean WTF? Really? I was trying to change the countershaft sprocket to a 15 tooth. The damn bolt broke off inside the countershaft...grrrrr. I was trying to remove counter clockwise. It just snapped...wow! Anyway, it is an M-10-1.50x40mm (Metric), grade 8.8 bolt. Had to drill and use an "easy out". But this time I heated it with a torch. Got it. Now to find a replacement the right thread and length...grrrr An interesting find while working on the bike
Looks like the bolt had actually stretched previously...the thread looks somewhat "cone-shape/ tapered" just short of the breakage point. As for the date stamp...it also might just be the date that the engine cases were manufactured (as the bottom end hasn't changed at all, AFAIK) Good on the Ezy-out to save another day.
I'm thinking the bolt was over torqued at the factory to stretch it out like that. The torque specs for that bolt is 19.0 nm. I barely turned the socket and "Pop". When I got the broken end out it was slathered with red locktite (dumb arses) inside the thread casing.
A good hardened bolt should just shear off, not stretch and twist like playdoh. Do you have a photo of the head markings? When I did my sprocket everything was fine. It may have been a little too easy to break loose.
It was a Grade 8 bolt. It was definitely over torqued as it was stretched and already yielding. This indicative of an over torqued bolt. Reference the following thread: http://www.advrider.com/forums/showpost.php?p=9126666&postcount=1
Heck I didn't even get to ride it. I finished the repair and it started raining and hasn't stopped. Figures right?
OK then, wonder if that is what they intended to put in? I had to look up the 8.8, didn't think it was hardened, and the way it stretched didn't look hardened. This site has a nice chart. http://www.boltdepot.com/fastener-information/materials-and-grades/bolt-grade-chart.aspx
I put a grade 10 bolt in as a replacement. I was just thinking that had that bolt failed at speed I could have been injured badly. What a crock of _ _ _ _! Not cool.
Starting to become obvious now why BMW couldn't flog off Husky soon enough to who ever was game enough to take it on, aye??
I dealt with metric bolts a lot when I was stationed in Europe. A 8.8 is almost identical to a Grade 5, regardless of size. On a side note, it seems as if all our bikes were assembled by very different folks. High turnover rate at the factory, perhaps? My countershaft bolt was easy peasy. However, my upper engine mount bolts were damn near impossible, and were found to be dipped in locktite when removed. Meanwhile, I got a message from a fellow TR owner this weekend because his upper engine mount (factory bolt never touched before) fell out on a ride and he was searching for a replacement.
The reality is you bought a BMW and BMW uses crap hardware. The majority of hardware on our bikes are BMW spec. I have snapped bolts on both my X-Challenge and the Terra trying to torque them.
Huh? Royal Enfield is high quality stuff. You should try a Ural. They are masters of inferior metallurgy. Check this out. What you see in the first photo is how your sidecar axle is supposed to look. This is the wifey's Ural. What you see on bottom is how mine looked after getting back from a 100mi ride (old Ural cargo tub on a Bonneville). That cotter pin saved my life. In all actuality, I don't think quality control is near what it used to be on any vehicle or motorcycle. There was a time when companies manufactured their products almost entirely, down to sometimes the smallest component. Those days are long gone. Multi-source manufacturing has improved some aspects of the motorcycle and auto industries, but often at the expense of others.
