has anyone out there (other than Spencer with his no longer available triton) used a custom frame on their original schlumpf hub?
If so, who made it? Anyone had a Hunter built with the schlumpf torque arm fixing? Or drilled a nimbus II or similar to fit it?
Basically I could really do with something that isn’t flexy, and has magura mounts (or is steel so I can get them fitted myself), but fits a Schlumpf hub. The hub has 90mm bearing spacing, so the KH frame (and other aluminium 100m spaced frames) is a no go for frame hacking.
(Bearing in mind my experience of Schlumpf hubs is a couple of rides on gkmac’s 29er and Mike Penton’s KH24…)
It seems to me that a steel Nimbus frame would be a pretty easy (and cheap) starting point. Bending it in 10mm shouldn’t do any harm (my 36er frame has been bent out to fit a super-wide hub, then back in again for my new normal-width hub with no ill effects). You’d probably need to make up some sort of spacer between the fork and the torque arm, but that wouldn’t be hard. And weld on brake mounts if you want to fit maggies. Got to be way cheaper than getting a custom frame made up, and probably just as good. I think Nimbus frames have machined bearing holders as well now.
Or are you after something that looks cooler? (nothing wrong with that). I think the multi-tube Blizzard/Hunter/N36 designs look nice, but Tue reckons his N36 is bendier than his old coker frame (not to mention heavier). That’s only from talking to him just after he swapped it over though - I haven’t seen him since he came back from RTL, so it’s possible he’s got to like it in the meantime.
grind off inner edge of bearing holder on torque arm side (you need this as the bearing holder has to not have an inner lip)
drill holes for torque arm bolt thingy. I think I may be able to use the schlumpf spacer / bolt parts if I am lucky, otherwise I have some similar parts hanging around from an old futon frame which might just do the job.
get brake mounts welded on (cost me a fiver last time)
The machined bearing holder version of the nimbus is 42mm not 40mm bearings, so I think I’m stuck with non-machined ones (or using a shim, but that’s probably just as bad? )
I actually have a nimbus 29" frame at home to try this on, I’m just slightly worried about using the non-machined bearing holders on the Schlumpf. Do you think there might be a problem with them, or should I be okay?
I forgot about needing to grind the flange a bit (ooer missus).
I would have thought machined 42mm holders with a properly fitting shim would be better for the bearings than the cheap pressed ones. On the other hand, I’ve done oodles of miles on my cheap frame (and I know you’ve done even more) with no bearing problems. With the old Schlumpf hub like yours it’s not as if the bearing holders need to be reamed up tight like they do for the KH ones - the bearings are just like normal unicycle bearings aren’t they?
I don’t think you’ve got anything to lose by using that Nimbus frame you’ve got, as long as you make sure the torque arm is spaced correctly and firmly attached so it’s not under any weird stresses, and that nothing rubs on anything. But, as I said before, I can’t say I’ve tried it myself and it’s not my £700 hub
BTW - I thought Roger built you a new frame to fit your hub after the Schlumpf frame broke, didn’t he?
Joe – you’ve failed to mention what size frame/wheel you want to use it in!
My recommendation:
The 36 Nimbus frame will fit the old-schlumpf hub, but it isn’t really wide enough. I recommend waiting for the KH 36 frame and getting the KH hub.
I used the 36 Nimbus frame with hand-ground bearing holders from 40mm to 42mm – DO NOT do this. It destroys the bearings due to the size being not 100% perfect. I’m waiting for a KH frame and not riding the 36’er anymore.
It is good to know that some of the hub failures were related to #2, it makes me feel a little safer about my hub. Is that what happened to Beau’s hub while he was training as well?
I plan on returning it for the beefier parts, but not for a while, and I guess as long as I don’t try to stop myself with one pedal rotation for the time being I will be fine.
Yes; we worked with florian, and figured out that the not 100% bearing holder was the common cause of our troubles. Also, having too tight a grip on the bearings will also cause trouble.
But note that Kevin’s 29’er had adequate (not too much) pressure on the bearings with his KH 29 frame, and his bearings (the smaller, older ones with the bad planetary carrier) failed. On the last day of the race they were starting to make some noise and become stiff when he turned the wheel. The new beefier bearings should solve this problem.
I think it’ll be fine - the bearing holder issue is only for the new hubs without the torque arm. If there was a torque arm on the new hub Corbin et al probably wouldn’t have had the problem… (insert long legal disclaimer here)
Joe’s Schlumpf wheel is a 29er, and he mentioned using a Nimbus 29er frame he’s got spare, so sounds like he’s probably not planning on changing it to a 36.
I had Rick Hunter modify a frame for me to use with my Harper-hubbed 36er. I imagine it would be pretty simple for him (or another frame builder) to mod for a Schlumpf.
When I first got my Schlumpf I was looking at putting it in to my Blizzard (Joe Rowing) frame. I think that could be done without any need to drill or even modify the frame itself; Use a triangular wedge of aluminium with concave edges that sits snugly in the V formed between the two legs. Once the torque arm is bolted in it wouldn’t go anywhere, and would be strong enough to take the forces applied. It’d look real neat too.
I’m sure you could mackle something up for your Nimbus frame though with a couple of jubilee clips and a piece of suitably bent metal. It’d be easy enough to test out, and if it works fine, then look at getting the Mag mounts brazed on.
Hey Joe, Rick Hunter made one for me a month before RTL. He made my handle too. I had ordered it in January but . . . no, I won’t go there. Really, it is a beautiful frame with 42 mm bearing holders (so, I feel pretty safe re: the bearing destruction issue). Of course, this was built for the Holm/Schlumpf guni/muni hub.
The frame was US$425 and though we talked about the handle price being between US$100 and US$150, he didn’t actually charge me for it because of the lateness of receipt of the order. Since it worked so well at RTL though, I’ve resolved to send him US$100 for the handle anyway.
I have a (very nice) frame top part that roger made, but it still has the bendy aluminium legs and brake mounts that twist out when you apply any braking force beneath it. With all the magura mounting gubbins it isn’t so bad, but it’d be nice not to have to run on standard mounts - it’s a big old hack. It also only really works on mine with the maguras on the mounts at an angle because the funny brake mounts don’t have a back in the same place as normal ones.
I was thinking drill two holes, same as on the proper frame, one big on the outside, one small on the inside - rather than hose clips - I seem to remember Dave tried hose clamps with no much success.
