Broken/Lost gear IRD 11-32
 

Was out for a ride with my daughter yesterday and at some point lost a gear. At 16 of 23 miles taking off from a stop light we suddenly found ourselves spinning free. Pulled over and on initial review it looked as if the lock ring on the cassette had come loose. Tightened it down as best I could by hand, moved us to the middle of the cassette and babied it home.

When we got back home I inspected the cassette, initially saw nothing, and went to put it back together and tighten it with the right tools. When it would not tighten I pulled it all back apart and inspected it as well as the hub again. This time i noticed a crack on the 21 tooth but that would not account for the looseness. Finally I went to the simplest question and counted the rings, whoops, only 9! At some point during the ride we lost the entire 13 tooth ring off of the cassette :eek:

So I ask, am I asking too much of the cassette? I ride with multiple stokers but most often my daughter. Normal Team weight varies from #403 on the low end to #455 however I do also ride with the Blind Stokers Club as a sub captain a few times a year and with this months stoker we topped out at #535 . The bike is about a year and a half old and has just shy of 1600 miles/50,000ft elevation. I checked the chain after the last ride and it showed just under 1/16 in stretch so I have ordered a replacement. Should I steer clear of the IRD cassette? Is there a good alternative wide range cassette if so?

Who installed the cassette? I never let a bike shop install my cassettes since having 2 lock-rings come loose. They frequently don't use a torque wrench and 40NM is a heck of a lot of torque. Or if they do, at least put a torque wrench on it yourself!

This was the factory cassette so installed by Cannondale. For the time being I installed an Ultegra 11-28 that I had on hand and made sure to torque it!

That's just COOL! Ripped the gear right out of the sucker.

IMO it's not the team weight but the power output that would damage the cassette. That being said, destroying the 13 [and 21 from what it sounds like] sounds like a manufacturer defect. There is far less torque on the smaller cogs than the larger (I think this is why the largest cogs are often attached together on a carrier). Are either the 13 or the 21 the first single cog? Certainly a new cassette and chain should be in order, and an inspection of the freehub body for gouges. Both SRAM and Shimano make a variety of wide-range cassettes and replacing/expanding upon your old one shouldn't be an issue.

As a blind stoker on a personal note, thank you for your support of your local blind stokers club, if it weren't for individuals like yourself many of us would never get the chance to ride.

Pedal on you powerhouse.
LKW

Thanks for all the input.

I imagine that the ease we experience is 20% easier gearing and 80% hopeful expectation.

Here's some pics of that which I am referrring to.

http://s29.postimg.org/4ao9j5wbb/photo_62.jpg
upload an image



http://s22.postimg.org/3rwnbytm9/photo_64.jpg
These Ultegra FC-6603 chainrings are forged, look great, shift great. The inner chainring is still a TA. I've got to find some black inner chainring bolts, because the silver ones are out of place (also, they are not flush). It'd also be nice to have a muted inner chainring that matches the other rings. Silver sticks out, and no one wants granny on display.

http://s29.postimg.org/nh6ijgj4n/photo_67.jpg
Finally was able to get rid of the Shimano FD, and use the Campagnolo Athena 11-speed triple FD, which looks a lot better, and shifts better too. The FSA tandem FD clamp pushes the FD out an additional 5 mm, and makes up for the difference in chainline between Athena (43.7 mm) and my Lightning (48 mm).

http://s30.postimg.org/xaj4idiz5/photo_65.jpg
The Shimano Ultegra 11-32 11-speed cassette. The Athena RD shifts it just the same as the Campy. It is nice having all that range on the cassette, and partly thanks to the 11-speed, jumps that aren't that big. The Athena triple RD has the long cage that takes up the slack.

I've heard of this once before. A friend, who is 150 lbs but pretty powerful, managed to break the 15-tooth cog on his Campy Record 11-speed cassette into two pieces. He was able to stop safely and pick the pieces up off of the road. The cassette was only a few months old, so he actually got it replaced by having the LBS send it back to the local distributor.