Skyline Chili wrote:
lanierb wrote:
Thomas Gerlach wrote:
teddygram wrote:
I was told that they would have a failure every 6 weeks with the OEM bolts.I would love to see a video of this person installing their bar. Something doesn't make sense if they are needing a new pair every 6 weeks.
+1. I'm 180lbs and I bomb down potholed roads in the aerobars at 45mph with no problems, and I've also moved my front end around countless times. No way those bolts should fail every 6 weeks. My guess is their torque wrench is off, if they're using one. Same thing with the seatpost bolts BTW. I'm even more sure that people shearing the seatpost bolts are overtightening them.
Despite the fact that you’re sure, you’re still wrong. Torqued properly, I had two shear on two different Gen 2 speed concepts. I’m 6’2” and very near the minimum insert which places the maximum pressure on the OEM nickel plated bolts.
Edit: I decided to rewrite my response. The Gen 2 SC has been around for four years and there have been tons of big dudes riding them without shearing anything, so sorry but that means your problem is either (a) you overtorqued the bolts, or (b) your SC is messed up -- out of spec or cracked seat tube.
Overtorque can happy lots of ways so that's a real possibility, especially since you managed to do it twice. You realize those bolts are only 5Nm right? They are like stem bolts.
Also, sorry but minimum insertion has nothing to do with it (if its within spec and not cracked or anything). The seat tube holds the post. The clamp keeps it from slipping down. The clamp is supported by the seat tube assembly and takes the sideways load. The screws merely provide clamping force and take no sideways load, even at minimum insertion, again unless there's a problem. Again, they are like stem bolts. If you're breaking them there's something wrong.