KH Moment Ti Hub

What a thing to notice on Christmas Day :frowning:

Has anyone else done this yet?

I don’t get it.

thats not a regular KH hub, figure it out…

thats crazy, do you have any ideas on how this happened?

I did a trials demo at the end of November, which was the last time I had any time to ride, just looked at my hub and noticed that :frowning:

It wasn’t a particularly extreme demo or anything, didn’t do any overly huge (like 1.5m+) drops.

It hasn’t been ridden a hell of a lot, mainly for street and the occasional bit of trials. No more than like 20 outings :stuck_out_tongue:

oh, have you talked to KH about it?

No I haven’t yet, I only just took the photos today :wink:

oh, that works.

ow damm…
a broken Ti hub :astonished:

It looks like the cracks started at the cutout KH logo.
Those logo’s are overkill and are not good for the strenght of the hub.
The holes in the flanges of K1 or Nimbus hubs are way better, since they are smaller and not to close to the welds.

Still, impresive work :wink:

Ti Hub

Appears to be stress fracture from metal fatigue. You know how a piece of wire bent repeatedly in the same place ultimately breaks? Well this appears to be a “stress fracture” from repetitive “flex” at the weld. Weld was defective to begin with.

Hey,

It looks to me like that hub had a defective weld.

Joe- thanks for the email. I will set you up with a warranty replacement on it.

Kris

Legend :wink:

I suggested this in an earlier thread.

Instead of having the hub like this:

   KH
KH    KH
   KH

To seperate it and put it like this:

  K
H   H
  K

Less metal cutout, and you still get his Ks and Hs on the hub.

Totally.

It does seem like a poor design

Holes save a little weight, and have that nice smooth radius to spread the stress. I like having KH on all the parts, because uni’s are kinda more a mixture of parts, on the high end, then any sort of model. Years down the road, should you want to sell a part to someone who only knows a bit, the KH branding may help show that it is a quality part.

It does seem that the KH hub cut outs have gone a bit to far towards branding, and away from the theoretical perfect design.

It is so cool to have Kris on this thread and dealing with this. He is likely right that this is more of a weld problem. Welders adjust their machine according to how the weld looks to them. On a cold mourning, a few hubs may be made with to cold a welder adjustment, before the welder changes the heat. When I was a commercial welder, I was paid by the hour. We did the best we could, but passed stuff from early in the adjustment process rather then make trouble for myself by saying anything.:o

Kris is great with his warranty, and a small number of failures like this are certain even with the best of design. Welders make mistakes, even a small distraction can cause the welder to slip up in a place. Welders will never admit this, because no one will notice if they say nothing !:wink:

It’s just happened to me too, on my 3 month old 36. Wish I had of seen this thread before getting my 36. I understand now that the hub has been redesigned, but I got an old version hub.

This happened to me while I was going down a very steep inner city carpark driveway. Really wouldn’t want anyone else to go through that dismount. It was the most ungracious fall I have had on a uni. Lucky not to have broken my arm.

I should add that I am still a ravid fan of KH gear. I believe that Kris continually improves his gear, to keep it the best. I just wish I could have bypassed this old style hub.

I love this hubs even they are welded disastrous! the problem is nt the design - in my opinion much better than the new one - the problem is the welding. If you find someone how can weld this professional it won´t frakture any more!
may be you have warrenty…

ti is not harmed at all when welded nor is it weaker after the weld. so welding the area where it was damaged should be fine. :slight_smile:

I agree that this is fixable, but from what I hear it can be hard and/or expensive to find a welder that can do titanium well.

If not done properly it will break either at the weld, or more commonly just after the weld.

A really good quality weld would require heat treating. Normally this would not be necessary but since you would be going over a previous weld I think heat treating the new weld would be required.

I don’t like the idea of trying to weld the old hub. The hubs don’t break while you are ambling along a grass trail. It happened to me going down a steep concrete driveway (office carpark). I was leaning back pulling up hard on the seat to maximise back peddle, when the hub sheared and dropped me instantly on my back. Luckily I had a back pack and helmet so it was only my arm that was injured. I really couldn’t have that happen every 3 months, let alone one more time.

Here is what the new KH ti hub looks like. It appears much much stronger than the old model I had. It’s a credit to KH that the design has been so radically improved.

I don’t do big jumps on my 36, although I am quite large and I do a lot of muni, which would find any weakness in the wheel. If you are very light or don’t do hills, the old hub might be fine for you.

I don’t suppose anyone has had a failure on the new ti hub?