Schlumpf hubs: general discussion.

[munirocks]

As the lucky owner of two Schlumpf hubs I must say they are a very significant addition to my riding. The geared 26 is a monster that can handle all kinds of terrain. When in high gear it has the speed of a 36er and in low gear it can deal with technical muni conditions. I really miss it now (it had the bearing thing again) and I'm waiting for the replacement hub every day... But I have learned by now that I have to be patient with Schlumpf and that it can take quite a long time until I finally get the hub back...
So at the moment I ride the geared 36 mostly. It's a blast too. I built that wheel myself with the instructions from John Foss in Uni magazine (not sure which edition) and with Roger Davis' spoke length calculator. When the other hub comes home I will build the 26" wheel myself too. I'm really looking forward to that, because that means I can finally ride the longer mtb trails that are further away from my house again.
For really steep and technical things I still prefer my ungeared KH24. It is definitely more maneuverable than the geared 26.

[siafirede]

Originally Posted by corbin

I think UDC will sell the complete uni with the hub built in.

I learned how to wheel build mainly because of the schlumpf hubs. My first build was with Chuck helping me out, but without a tension gauge it yielded a weak build, and I broke a lot of spokes.

Two of my friends, Ken Adelman and Bronson Silva, ultimately showed me how to build a proper wheel. Ken built a few wheels for me (ungeared and geared), and Bronson did one. Each time they built it I watched and learned how to do it. I then bought a tension gauge and started doing it myself. I usually follow the lacing pattern of another wheel as a guide, and use a frame as a truing stand.

corbin

Is there a certain point where after you break X amount of spokes you should just completely rebuild the wheel with all new spokes? I hadn't broken a spoke on my geared 36 for the first 700 miles or so, but now I have broke 4-5 spokes and keep getting it trued. I also just got my first flat tire EVER in my many years of riding a 36er =[. I wonder if it had to do with overtightening one of the spokes or something.

[corbin]

Originally Posted by siafirede

Is there a certain point where after you break X amount of spokes you should just completely rebuild the wheel with all new spokes? I hadn't broken a spoke on my geared 36 for the first 700 miles or so, but now I have broke 4-5 spokes and keep getting it trued. I also just got my first flat tire EVER in my many years of riding a 36er =[. I wonder if it had to do with overtightening one of the spokes or something.

Ken said it is best to *always* use a new set of spokes when building a wheel. They build internal stresses that can't be seen when the wheel is built.

Was your wheel built with a tension meter, or just by truing?

FWIW, my wheel that I built with Chuck (without a tension meter) lasted quite a while before I started popping spokes. Eventually the hub failed, and I rebuilt it with a new set of spokes.

But, I don't really know the answer to your question.

corbin

[MT High]

Originally Posted by siafirede

Is there a certain point where after you break X amount of spokes you should just completely rebuild the wheel with all new spokes? I hadn't broken a spoke on my geared 36 for the first 700 miles or so, but now I have broke 4-5 spokes and keep getting it trued. I also just got my first flat tire EVER in my many years of riding a 36er =[. I wonder if it had to do with overtightening one of the spokes or something.

If you broke the 4 -5 spokes all in a short period of time (am I reading this right?) I would consider rebuilding the whole wheel with new spokes.

When I bought my 36'er I had 3 spokes fail not long after I bought it. Shortly after I replaced them another 3 broke so I had the whole wheel rebuilt by someone who knew what they were doing. It was 12 months before the next spoke broke and then 6 months before a second spoke broke.

Good quality spokes help too.

(What am I doing in a Schlumpf thread?)

[Jeremy1981]

Originally Posted by siafirede

Is there a certain point where after you break X amount of spokes you should just completely rebuild the wheel with all new spokes? I hadn't broken a spoke on my geared 36 for the first 700 miles or so, but now I have broke 4-5 spokes and keep getting it trued. I also just got my first flat tire EVER in my many years of riding a 36er =[. I wonder if it had to do with overtightening one of the spokes or something.

It is possible that with all the messing with your nipples (perv!) the thin rubber band that protects the tube from the inner side of the nipple could have gotten dislodged, twisted, or pinched. You should always take the tire off to do much of anything with the wheels, and if you're doing more than a truing touch-up let the air out of the tire at a minimum- and be sure to double check the protector whenever you have the tire off.

That said, replacing all the spokes and rebuilding the wheel is really more of a comfort thing- as mentioned, use good quality spokes of a large enough gauge, if you're breaking too many you may want to bump up the gauge a step to make them stronger (and heavier). Personally, I go for beefy spokes on my unis, because I'm more concerned about what happens when I take my 36" down a flight of stairs than the extra grams of spoke weight. (I also happen to use extra thick thorn resistant tubes and kevlar thorn protectors on all my unis for peace of mind- they work against glass in the urban jungle too, and I've pulled glass pieces out of tires without flatting before. It weighs more, but it makes me feel better, and I've never gotten a flat while riding that way, not even a snake bite/pinch flat.) If your spokes are too thin gauge, it won't matter how well built your wheels are.

Good luck!

Jeremy

[siafirede]

To respond to the three replies above...

My wheel was originally built by a wheelbuilder back in DC, but I don't believe he had a tension gauge...he did it by feel. It was great for 700 miles. After I broke a spoke, I brought it back to fix it, a quick fix was done and not much more effort was put into it...I immediately broke another spoke on my next ride. I then brought it to a friend who is a great wheel builder and he used a tension gauge to true up the wheel and replace the spoke...and the wheel seemed really nice. After <150 miles I broke another spoke, and had someone fix it up and then I had a flat. So it is very possible that it was overtightened and I had a pinch flat.

I just ordered a few more replacement spokes from UDC with my last order (gonna try out 165mm cranks and the KH T-bar) - so I am now going to bring it to another bike shop to fix up the wheel. If I get ONE more broken spoke...I guess I should give up hope and order a whole new set of spokes and get someone to completely rebuild it.

I have never had any issues with broken spokes on my ungeared 36er, but I am sure that the extra force from the high gear and the fact that I use a brake with my g36 doesn't help. It is getting to the point of being very annoying and I hate it when my ride is not reliable.

Would 4 cross help my situation out? I know most people just use 3 cross, but maybe my wheel would be more reliable with 4?

[Rowan]

Originally Posted by siafirede

I hadn't broken a spoke on my geared 36 for the first 700 miles or so, but now I have broke 4-5 spokes and keep getting it trued.

You probably remember this thread about spokes breaking since you were in it. Where are your spokes breaking? Did you try spoke washers? I've only had one spoke break on my latest wheelbuild with the M3 stainless steel washers so far. I don't suppose you get the same problem with the hole being too big on the geared hub.

[corbin]

Originally Posted by siafirede

To respond to the three replies above...

My wheel was originally built by a wheelbuilder back in DC, but I don't believe he had a tension gauge...he did it by feel. It was great for 700 miles. After I broke a spoke, I brought it back to fix it, a quick fix was done and not much more effort was put into it...I immediately broke another spoke on my next ride. I then brought it to a friend who is a great wheel builder and he used a tension gauge to true up the wheel and replace the spoke...and the wheel seemed really nice. After <150 miles I broke another spoke, and had someone fix it up and then I had a flat. So it is very possible that it was overtightened and I had a pinch flat.

I just ordered a few more replacement spokes from UDC with my last order (gonna try out 165mm cranks and the KH T-bar) - so I am now going to bring it to another bike shop to fix up the wheel. If I get ONE more broken spoke...I guess I should give up hope and order a whole new set of spokes and get someone to completely rebuild it.

I have never had any issues with broken spokes on my ungeared 36er, but I am sure that the extra force from the high gear and the fact that I use a brake with my g36 doesn't help. It is getting to the point of being very annoying and I hate it when my ride is not reliable.

Would 4 cross help my situation out? I know most people just use 3 cross, but maybe my wheel would be more reliable with 4?

A 4 cross wouldn't help.
-corbin

[siafirede]

Originally Posted by corbin

A 4 cross wouldn't help.
-corbin

Why is that? I would trust your judgment more than mine since I have zero wheel building experience, but the Schlumpf has pretty large flanges, and from some brief research online it seems that 4 cross is better suited for large flange hubs.

[corbin]

Originally Posted by siafirede

Why is that? I would trust your judgment more than mine since I have zero wheel building experience, but the Schlumpf has pretty large flanges, and from some brief research online it seems that 4 cross is better suited for large flange hubs.

It is just what I heard from some sources; the extra strength isn't worth it. If you are breaking spokes, it is probably due to the wheel build.

--corbin

[siafirede]

Originally Posted by corbin

It is just what I heard from some sources; the extra strength isn't worth it. If you are breaking spokes, it is probably due to the wheel build.

--corbin

I just got my wheel back from a good wheel builder here in Denver and he also confirmed that 4 cross would not be good for the geared 36er. There was a long explanation. I will be taking a wheel building class sometime soon because I need to learn how to build and true my own wheels.

The wheel feels great now, even tension and true. I can't wait to get back on my g36 and try out my new saddle and KH T-bar and 165mm cranks.

[siafirede]

Originally Posted by siafirede

I just got my wheel back from a good wheel builder here in Denver and he also confirmed that 4 cross would not be good for the geared 36er. There was a long explanation. I will be taking a wheel building class sometime soon because I need to learn how to build and true my own wheels.

The wheel feels great now, even tension and true. I can't wait to get back on my g36 and try out my new saddle and KH T-bar and 165mm cranks.

Just wanted to update this...165mm cranks on the geared 36 feel awesome. It is noticeably slower in low gear but high gear feels great, and shifting is actually very easy (I think I was just having problems with 165s bc Roland's pedal/shift button set up is different).

Once it gets a little warmer I will tackle some mountains out here and see how the set up works. I think 165s will handle long mountain climbs in colorado better than 150s.

The T-bar is pretty cool as well, it feels nice having the handle in a comfy position a little bit further out than a T7, but I do miss the control and acceleration I got with the shorter handles on my GB4.

I love my kh/schlumpf!

[From the Woods]

Last week I ordered a KH26x3, 137/165 dual moments and a Schlumpf hub. I can't wait to ride it but since I often ride on muddy trails I wanted to know if the dirt can be much of an issue. Do you clean the hub and cranks everytime it gets dirty?

And another concern is about shifting by accident. Does this happen often or never? I am thinking of riding technical XC/downhill trails where bumps may cause your foot to move on the pedal and then you shift... and... UPD

[hugo]

Originally Posted by From the Woods

And another concern is about shifting by accident. Does this happen often or never? I am thinking of riding technical XC/downhill trails where bumps may cause your foot to move on the pedal and then you shift... and... UPD

So far, I never shifted by accident, but: I do not ride on really rough terrain with my KH29. I would say that it can happen if you are really unlucky, but it should not be a big issue. My guess is that it will happen much less frequent than UPDs for other reasons.

[siafirede]

Originally Posted by From the Woods

Last week I ordered a KH26x3, 137/165 dual moments and a Schlumpf hub. I can't wait to ride it but since I often ride on muddy trails I wanted to know if the dirt can be much of an issue. Do you clean the hub and cranks everytime it gets dirty?

And another concern is about shifting by accident. Does this happen often or never? I am thinking of riding technical XC/downhill trails where bumps may cause your foot to move on the pedal and then you shift... and... UPD

I haven't really ridden in really muddy conditions with the schlumpf but I'm sure it will be just fine.

I have never accidentally shifted and you shouldn't have any accidental shifts with those long 165s.