SRAM E1 vs. D1

Tire boots, TPU tubes, cornering, parking brakes

Regarding last week’s post on my multiple punctures:

Dear Lennard,

Regards your recent post, whatever happened to the dollar bill or credit card as a shim for a sidewall or large puncture? I guess I'm dating myself.

Michael

Dear Michael,

Thanks for pointing that out, and far from dating yourself, that’s still a valid fix. I forgot to mention it, but indeed, we did put in an empty energy gel package as a tire boot inside the sidewall against the hole out of which I had pulled the Stan’s Dart. Here’s that gel packet, still curved from being squished between the tube and tire.

Just to clarify, though, a tire boot like that would not have sufficed in a tubeless scenario unless you could figure out a way to get it to stay in place with all that slippery sealant sloshing around. A tire plug can plug a hole without removing the tire bead from the rim, but if there are a bunch of casing threads cut creating a bulge in the tire, it (or the multiple plugs required for a bigger hole) does nothing to reinforce that area. With an inner tube, a boot stays in place and is a great thing when multiple cords in the casing are severed. It prevents the inner tube from sticking out of the hole and either bursting or getting abraded or punctured.

Even with that gel-packet boot in there, I still didn’t have the confidence to air the tire up hard enough to get it to seat properly to finish the Zinn Fondo. Happily, it made it back to the shop and home okay, albeit creating a bit of a bumpy ride at speed on smooth pavement. I did one more ride to the shop and back on it before I stopped pushing my luck and finally put on the Challenge Gravine that I had intended to mount before that ride.

― Lennard

Dear Lennard,

I think we mechanics are often guilty of living by the classic motto...

“Do as I say, not as I do.”

I’ve definitely found myself in the same boat... Taking off on a ride with tires I would’ve insisted a customer replace, or heading out for a ride missing a piece of gear I’d never let a rider leave without.

Really enjoyed the article as it hit home in all the best (and slightly humbling) ways.

Tom

Dear Lennard,

I have a question for your column. Do the older SRAM 12-speed cassettes and chains work with the new E1 systems? Also, are the D2 and D1 derailleurs compatible with the new E1 shifters?

Nick

Dear Nick,