So I got my 26" oracle frame in the mail today, but as I was assembling it, the hub just wouldn’t match up with the frame. I thought maybe one of the legs was bent a bit. I pulled one leg toward the hub and it fit properly onto the wheel’s Bearings. It seemed to work…then I realized later on that my hub has a 92mm pitch and the oracle calls for a 100mm pitch. Are there any risks to me riding with this set-up? I’m 125 pounds, I can barely hop higher than 6 inches, and I prefer to ride fire roads and easy mtb trails. Will I ruin my frame or hub or both?
I wouldn’t do it.
Aluminum doesn’t like being bent, so don’t try to cold set the frame to fit the hub. The bearings will not be seated squarely in the holders which will cause uneven and premature wear. The outward force on the bearing, caused by the frames desire to go back to its normal position, will pull the bearings out of place on the spindle.
Outside of that, I don’t think there’s any other reason not to run your setup. For me that would be enough to warrant a new hub.
If Torker hubs have a straight spindle without a raised bearing seat, you may be able to pull the bearings, add a 4mm spacer to each side, and seat the bearings against the spacers. This will only work if you have 4mm’s to spare between the crank arms and the bearings.
So I emailed Torker asking what the bearing pitch was on the 26’’ LX. Someone replied with the following:
“They are listed on our spec sheet as 105mm. I believe that is to the center of the cradle, so 100mm is probably right.”
So I guess if my Torker LX hub is actually 100mm, the Nimbus Oracle frame should have fit on the bearings easily. When I initially got the frame in the mail, I thought one of the legs didn’t look centered, but I didn’t think too much about it because this is my first round-crowned frame, and I was blinded by the excitement that it had finally arrived. I didn’t have to pull the leg in TOO much, so I guess if Torker is correct, my frame was slightly “untrue.”
No big deal. It seems to works great now.
I’m going to ping this thread because that’s what I’m about to do for one of my race unis, and just want a few more opinions.
I have various Triton Ti frames that are made for a standard 100mm bearing pitch, but the forks flex enough that a 92mm hub seems to clip in securely.
The issue of the bearing not seated squarely in the holders doesn’t seem to make much sense to me, especially on a larger frame (I’m using a 29’er frame). With 4mm flex on each fork leg, the angle doesn’t change that much.
In terms of the force of the frame forcing the bearings apart, I haven’t ridden it long enough to see if it does occur, but I don’t think there is enough force from the fork legs to do it. It’s also clipped in place and held there by the crank spacer.
Has anyone else used this setup? I’m building up a 700c race uni with an Nimbus Eclipse hub…it’s lighter and will give me a lower q-factor compared to the Nimbus Equinox hub. The whole Uni should come in well under 3kg. I’m currently running the same hub but with a 24" race wheel.
I do have experience going the other way…I used a Coker frame designed for a 92mm Suzue hub with a wider UDC hub. It works fine, and has done so for thousands of kms.
That was in response to using an aluminum frame. Ti is much more flexible than aluminum. I don’t know if it will put as much pressure on the bearings.
There is probably enough slop in the cartridge so that the outer and inner races will be seated correctly, but the races won’t be square to each other. That will lead to uneven wear of the races. It’s probably not a huge deal. It could be mitigated by removing your wheel and reinstalling it to move the wear point sort of like we do for tires. That will probably only help with the outside races though.
Do you have enough space on the crank side to put 4mm spacers behind your bearings? I guess you could move your ISIS spacer between frame and bearings, and use the bearing itself as the crank stop. Of course this only works if the bearings aren’t on a shoulder. If the spindle is constant diameter I think it should work.