Geared 36 accident

I have been running my radial TA on my non-geared N36 for a while now between 45-50 psi with no problems but today on my geared 36 I aired the tire up to 45 psi and took off for a ride but on mile 12 I heard a gunshot like pop and down I went as the tube popped and blew the tire right off the rim.
Fortunately for me I dont ride as fast as some people here and this time I am definetely happy for that since I was in geared mode and at a cruise of 16-17 mph it hurt bad enough.

mmm That makes me think that I should perhaps buy one of those new rims, lighter than my current airfoil and the proper size.

I had my TA pop off my rim the first time I rode it. Not something you want to happen after spending $1000 on a unicycle.

Glad you are OK. 17mph is plenty fast.

I think you just convinced me to spend the extra $100 to get a new rim if I end up getting a geared hub. The Airfoil shall be relegated to Coker MUni.

Glad to hear that you didn’t bail to bad. I’m not sure if it is more reassuring that it was your equipments fault- and not your own skill. I had my first genuine UPD at speed on my N36 this morning. Was on a long gentle downhill section and my cadence got a little out of control- i came off when i hit a bit of a lump in the road and lost my left foot from the pedal. It was strange because i managed to do the one footer thing for a few revs but as i tried to get it back on i came off for good. The possibility of crashing off a G36r makes me shudder though.

saskatchewanian- are you planing on using the KH/ISIS or first production shlumpf geared hub for your G36r?

Keep riding, keep safe (no land speed record attempts please!)

Are you sure it’s not the bead or casing that’s broken? Or did it just pop off the rim for no reason?

There were a bunch of Coker tyres that seemed to have some trouble with bad casings or beads. I think the TA tyre might be made in the same factory.

I had a couple of beads and casings break on the Coker tyre. Two were from using Tubeless and I think one from using a tube. I’m using the 1st generation airfoil which I believe is actually bigger than the current bunch of airfoils. It’s hard to get on and hard to get off.


I just figured it was from the over inflation. Not just the tire came off the rim but the tube popped and has a tear in it about 8" long
I know my non geared 36 has the good airfoil rim but the geared 36 is only about 4-5 months old so maybe it has something to do with the rim.

Sorry for the mini-threadjack but I am going to wait for the 2008 “regular” hubs to become available. I plan to put it in a 26" wheel until I feel comfortable with shifting etc then move it to a 36. Hopefully I will be fully comfortable with it by RTL.

Edit: daytripper, I would be willing to bet that you got a rim from the undersized batch. I know I did and I got mine last april.

Does this mean I’m stupid if I run my TA tire / Airfoil rim combo at 70 PSI and plan on getting a geared ISIS hub as a dropin replacement for my current hub?

I’ve run my tire at 50 PSI for three months, and over the past two weeks, have started putting 70 in it after trying 55 and 60 and concluding, ah, what the hecks, may as well try for the 70.

Let me say, though, the TA tire feels AMAZING at 70PSI. So smooth and hard, like my 23c road bike tires at 120, almost. I think a gear and 70 PSI tire will be amazing… I’d just hate to blow out at 25 miles an hour (about like 17 or 18 on an ungeared if you comp up for controllability a little bit) or something obscene like that.

Wow, I run my tire at a little over half that. I never go over 40psi.

That sounds like a waste of a wheel build! Just put it in the 36 from the start! While practicing shifting just practice at a slow speed and you will be fine.

Do you have enough time for that? Any word on when the new “road” hub is coming out?

I’d just put it on the 36er and be done with it (if that’s why you’re planning on using for RTL).

To get back on topic. There was a rash of this same phenomenon happening last year, and I believe the UDC response was that this was due to a batch of bad tubes. Do you have the “x” rim? …I still don’t quite trust those.

edit: I run my non-“x” wheel at 50 psi, and the “x” wheel at 40-45 psi.

I have run my non geared airfoil 36 as high as 60psi with never any problem. Granted this is an airfoil rim from a couple years ago where as the new geared 36 airfoil rim is only a few months old, I have spare 36 tube here so I will change it and will again try to air up to 45-50 and see what happens.
Although I am tempted to order the new night rider tire and maybe try to put a 29er tube in it.

I would probably only have it in a 26" wheel for a week or two. I build my own wheels so really it would only really cost me $10 in spokes more than putting it strait in the 36.

My confidence in my undersized Airfoil is slowly going up and up. The first time I rode it it blew with the recommended 30 PSI. I don’t think the tire was seated properly when I got it and never checked before the ride. Depending on the trail/road and the season I run 20-40 PSI. I tried 50 but felt a bit harsh to me. Maybe it would be good at high pressures where is no frost cracks in the road.

I check to see if my tire is seated properly every time I adjust the air and whenever I bottomed out the tire on a drop. I have had the tire shift on lower pressures but haven’t had any more blow-outs.