[toyman]

Riding local trails yesterday and went over a log crossing. It was about 30" high and when I crested it, I sat back in the seat pretty hard (accidentally) and heard a sharp crack. I stopped on the other side of the log crossing to see if what broke. I checked over all the welds from the head tube to the bottom bracket and around the seat tube. Everything looked ok. I removed the rear wheel and squeezed the rear of the frame where the wheel mounts, and there was a lot more flex than I expected. I could easily squeeze the distance between the wheel mount by about an inch on both sides (2" total I guess?) I remounted the wheel and it seemed ok. Then as I was riding, my rear brake started hanging up. I stopped and readjusted it, but it still wasn't spinning 100% free? Then a litte further in the ride, 2nd gear was searching. I made an adjustment on that and finished the ride. My confidence in the bike was a little shaken. I haven't had a chance to clean it up real good and go over all the welds yet, but it's on my list this week.

Should the rear of the frame be that flexy? Any other areas to look closely at aside from the welds? I'm driving about 2 hours for a ride this weekend and don't know if I'll bring this bike, unless I figure out what happened.

 

[HamfisT]

Sounds like an awful lot of flex to me...

Clean it up good and go over it with a magnifier... not worth getting hurt from a catastrophic failure.

 

[Dark_Rider]

I would check for cracks at the top tube/seat tube/seat stay junction. Both at the top tube gusset and in your situation the seat stay welds.

At this point, if I was in your shoes, I would send in the frame for a "crash" replacement and ask for one of the Moto frames instead. The replacement cost of the frame should be the same. Though seat tube diameters and headset type of the two frames are different.

 

[TwoHeadsBrewing]

I'd sit on it and have someone else look at the frame closely with it under load. If there was a crack, then it might be hard to spot unless there is weight on it. Do this before the next ride because you don't want to find out while going 20mph through a rock garden.

 

[toyman]

It sucks because I'm riding at Raystown PA, about 2 hours away on Saturday. I guess I'll be taking my Scott Vertigo. Not that I mind riding the Scott, but the 29er is a blast on the trails there. I'll be cleaning her up real well and going over everything in bright light to see if I can find out what happened. Thanks for the feedback.

 

[toyman]

So, I cleaned up the bike real well, got out the magnifying glass and went over all the welds. From where the rear wheel mounts to the seat stays to the seat tube, head tube, and bottom bracket. Everything looks good. I even sat on the bike and had my wife take a look to see if there was any movement. The rear brake isn't dragging and it's shifting well again. The flex on the rear triangle is left to right, none up and down. I also tightend up the deraillier hanger. I quickly checked over the spokes and happily/concerned, I came up with nothing? I took it out and rode it hard on some 'rip wrap' (big drainage rocks) on the side of my road. It didn't make any noises or get squirrely. Did a few bunny hops and it seems all is well? I guess I could have kicked something up that hit the frame to make the noise, but I have no idea why I had the issue with the brakes/rear deraillier. I'm still on the shelf if I'm going to take it to Raystown tomorrow. I guess it will be an early morning decision!

 

[TwoHeadsBrewing]

Is it possible your skewer was loose and that was causing the weird feeling and dragging brake? Out of nowhere my front wheel had some play in it, and I though for a bit it was the hub going out. Turns out my skewer had loosened up for whatever reason, so I tightened it and everything has been fine for several rides.