WARNING 07 KH ISIS crank removal

The ISIS spec allows for the use of either M12 or M15 cranks bolts. Koxx and KH both use M12 crank bolts that have a 1.0mm pitch. So you need a 12mm x 1.0mm pitch tap.

Truvativ sells a M12 self extracting CroMo crank bolt set that I used to convert my Koxx cranks to a self extracting setup. I got this idea from using a set of Truvativ ISIS cranks on my Koxx hub (see my avatar). These should fit the KH cranks to make them self extracting.

So Truvativ cranks fit the koxx hub? My god, will this Isis or not Isis ever stop?

Hah the same thing happened to me. I kept on turning it and I was like, why the hell is my crank not coming off. Then I tried to pull the crank puller off and found that it was screwed in, man did I ever feel dumb :P.

From what I have read some Koxx hubs are within the ISIS spec and some are not. I guess I got lucky to have one that was within the ISIS spec. I have also read that a hub and set of cranks can both meet the ISIS spec but if the hub is on one end of the spec range and the cranks are on the other, they may not fit together.

So it may be that Koxx and Truvativ are just on one end of the spec and KH is on the other.

I highly doubt there were some hubs that are isis and some that arn’t, I bet there were some people that own the koxx hub that are dumasses, and some that arn’t. Resulting it different reports on its being isis or not isis. Truvativ is a pretty common Isis crank in the bike world, If that fits…Hmm…I’d say most would. Someone needs to go to a bike shop that carrys tons of isis cranks and see which fit and which dont.

I did try to mount the Truvativ cranks on my Koxx Red Devil just to see if they would fit. The Truvativ cranks fit but they would not tighten up against the spacer. There was a 1/4" gap between the spacer and the crank (there is no gap when I mount the Truvativ cranks on my muni). So it looks like the hub on my Red Devil is a little bit bigger than the one on my muni.

I think it was one of Roland’s post on the German forum that talked about the variances in the Koxx hub.

But the splines sink into the crank properly right? I suspect Yoggi will fix the slight variation in the 07 koxx hubs after reading all these koxx no isis threads.

Yes, the splines fit correctly. My guess is that the hub on my Red Devil has a flute taper (the milled out portion) which is too steep so it does not allow the crank to slide completely onto the hub. My Koxx cranks fit fine with no gap. It would be interesting to know if this is defined as an incompatible ISIS hub.

I wish Yoggi would give us a detailed explanation about the Koxx ISIS problem and if it will be addressed in future Koxx hubs/cranks. This would help keep down the number of “incompatible Koxx ISIS” threads.

im thinking about buying a kh isis cranks and hub
you guys know if it fit in the nimbus frame ?

Nimbus II frame?

I am not sure about the regular, rounded Nimbus frame, but if I remember right, you ordered the Nimbus Hoppley, and that comes with the Nimbus II frame, so I hope your using that one. lol

Anyways, because the Nimbus II frames bearing holders arent machined and perfect like on a kH frame, they will hold the 42mm bearings from KH. =p

The KH ISIS hub has 42mm bearings and I think most nimbus frames take 40mm bearings. The KH ISIS hub does not have the option of installing the Torker DX 40mm bearings to make it fit in 40mm bearing housing frames.

If you search the forum you will find two answers:

“Yes you can with no problems, I have done it for years.”


“No, it will cause your bearings to fail.”

I have not run a 42mm bearing in a 40mm bearing housing frame for more than a few hours. So I can say
yes it will fit but I am not sure about the long term durability of the bearings.

If you do order a KH ISIS hub and cranks and plan to put them in a nimbus frame, I would order a spare set of bearings because the KH ISIS bearings (made by Qu-ax) are 42mm x 24mm and are not a standard bearing size.


Thanks for the tap size info

Help pleaese!

I’ve done the same anybody know how I can fix it?

Just order a M12 tap and a new bolt and you will be fine

dw fixed (well planned weekerning/ hammer) :wink:

I did do it for years (KH 03 hub in nimbus II frame), it runs no problems.

Hell even if they do fail after two years, new bearings are about £6 or something, lot cheaper than getting a 42mm frame.

i remember reading a tip somewher that said you put a penny or something in before the crank extractor. can anyone confirm this?

Evan, if you’re going to be acerbic, you really should stick to topics you know something about.

ISIS is a standard. If the cranks you manufacture are the only ones that fit properly on your hub, you’re not following the standard. “Slight variation” is not acceptable.

Koxx-One is not offering two hubs, one using M12 bolts and one using M15. ISIS cranks require ISIS crank arm remover. Square taper crank remover has much smaller area to push on spindle…hence it getting stuck inside ISIS spindle threads… no fun as a couple of you have found out. Any bike shop should have ISIS crank arm removal tool.

Per K1 cranks on other spindles. Last week I tried the standard K1 crank that comes on Devil 19s etc…) on 4 other brands of ISIS spindles. They fit well. Next week or so I will be getting in the LIGHT and STREET cranks in and I will try them on other ISIS spindles. Let me know if anyone is interested in my findings.

Per crank installation. I have found the best way to get good seating of cranks to spindle is with a rubber mallet. Lay the UNI/bike on its side so that the downside is touching ground/wood (place towel in between so as not to scratch up your cranks/spindle), place crank on upside… hit forcefully 3 or 4 wacks with rubber mallet. This seats the crank onto the spindle well and greatly reduces odds of them loosening up quickly. Though you should always check crank bolt tightness numerous times after installing cranks (particularly new ones).