WaitUpForMe

Has anyone had an issue with 1/8" EAI cogs on fixed/fixed IRO hubs? Specifically, the lockring won't thread completely onto the hub before bottoming out against the cog. Perhaps the EAI cog is simply too wide?

My plan (until I build a new wheelset someday) is to use a 3/32" 17T Soma cog with one bike, and flip the hub to a 1/8" 18T EAI cog for my other fixed-gear. I have a Campy lockring for the 1/8" side.

I'll probably try some more troubleshooting tomorrow, but I'd appreciate any thoughts until then. And in case you're wondering, the 1/8"-chain bike has tubular rims and tires, and I want to use my clincher rims for both bikes. Or maybe I should just start carrying around a tube of sealant and use the tubulars . . .

r0cket-

Erm. I'm pretty sure you shouldn't use a Campy lockring w/ that hub.

Anyway, my 1/8" Soma fits fine, and according to the info on sheldonbrown.com, the EAI is actually thinner than the Soma, so you shouldn't have problems, but who knows how accurate those figure are anymore.

Also, you can run a 3/32" cog w/ a 1/8" chain w/out problem, so unless the 17t gives you too step a gear on the other bike, you can just use it that way.

Lucky-Charms

Campy lockrings should be 1.32" x 24 TPI whereas durace are 1.29" x 24 tpi. I know that a durace lockring fits snugly on my IRO hub, so I'm not quite sure how you are putting a campy lockring on.

Like r0cket-, according to sheldon my durace 1/8 is thicker than an EAI 1/8, specifically my durace has a total thickness of 8.58 vs the EAI at 8.24. It seems improbable that your EAI cog is thinner than my durace, and r0cket-'s 1/8 soma, yet is still too thick for the IRO hubs.

I also partially agree with r0cket- about the 17t 3/32 on a 1/8" drive train. It can be done, without much of a problem, but it will be noiser. If stealth is your bag, you may just want to look into getting a new lockring, because that's where I believe your problem is.

heebro

[QUOTE=WaitUpForMe]Has anyone had an issue with 1/8" EAI cogs on fixed/fixed IRO hubs? Specifically, the lockring won't thread completely onto the hub before bottoming out against the cog. Perhaps the EAI cog is simply too wide?

EAI 15t on the track side of an IRO flip flop. Works fine. Dura Ace lockring. Campy is a different thread anyway as already stated.

12XU

This thread title scared me, as I'm almost ready to put my 1/8" drivetrain using an EAI cog on my IRO hubs...

WaitUpForMe

I'll pick up a Dura-Ace lockring on my next trip to the shop, then. I do like a silent drivetrain.

Thanks, everyone.

orange

Hey all, I just built up a wheel, Phil Wood hub, EAI 1/8" cog, same problem... the stock Phil Wood lockring is only maybe halfway threaded on when it's snug against the cog. Any advice?

thanks

bostontrevor

WaitUpForme, have you already threaded the Campy lockring onto that hub? If so, look carefully at the lockring threads and make sure that you haven't crossthreaded and destroyed them.

46x17

I have been running EAI cog with DA lockring on an IRO hub for about a year now.
The setup works perfectly well since the thread pitches are the same.
I know two other people that run the same setup and have not reported any problems.
Campy lockring on an IRO hub is a bad idea, since the thread pitches are not the same. If your lockring does not thread on quite all the way, but still fits snuggly against the cog, you should be fine as long as it is not sticking out too far. Around 80% thread engagedment should cut it. What really hurts your hub is when you can tighten the lockring all the way and there still remains a gap betw. lockring and cog.

WaitUpForMe

I did start to thread the Campy lockring on the IRO hub, but it didn't seem right, so I took it back off. I certainly didn't try riding with it. I found a small shaving when I removed it, but the lockring spun right back on the Campy hub with no problem. Thanks.

Campy/Phil Wood lockrings are 1.32" (33.5 mm) by 24 TPI, and Shimano-compatibles are 1.29" by 24 TPI -- they're very close. Close won't cut it with a lockring, of course.

bostontrevor

The lockring will spin right back on the Campy hub. That's because the ring is steel and the hubs are aluminum. You need to inspect the threads on the IRO hub to make sure that they're not too badly damaged.

WaitUpForMe

And now for my next trick . . .

Here's what I did this afternoon. I removed the wheel with the IRO hub, and then removed the Soma lockring from it. I threaded the lockring onto the other side of the IRO hub. It took a couple tries to get it started, and it felt just a little rough in a couple places. I worked the lockring back and forth and everything smoothed out. In my judgment as a prior helicopter mechanic, I'm signing it off safe for flight.

Then I put the 1/8" EAI cog on and tightened the Soma cog over it. There was a slight amount of lockring overhang off the edge of the hub threads, which I gather is fine, as stated in one of the posts above (the "80 percent rule" ). Then I removed the EAI cog and reassembled the other side and replaced the wheel, because I still haven't got my Dura-Ace lockring yet!

I tried using a chain whip to remove the 3/32" cog from the hub, and that sucker is on there but good. When I have to remove it, I'm going to have to reach into a bag of tricks.

It's all good. Thanks again.