HelluvaStella

Crosspost from Utility Cycling and Commuting forums:

Hello,

I'm building a rear wheel for my Schwinn Twinn tandem. I researched several internally geared hubs and decided on the SRAM Spectro 7 with drum brake. After much searching, I found a few websites that listed them, but all have told me they were not in stock. The company I placed my order with told me they were waiting for QBP to get them from SRAM, the 2008 shipment of them has not left Germany.

Does anyone know if this is the case? Any tips on an LBS somewhere that might have one of these lying around?

jgedwa

Good luck. QBP optimistically lists all the hubs and many parts (shifters and whatnot), but they do not seem to actually have the hubs.

Try a couple of things: call bike stores and see who might have an old dusty one laying around, and save a search on Ebay and wait with your credit card handy.

I have one of the hubs on my girlfriend's bike. (Actually, an older Sachs. But it is exactly the same.) It is a nice hub that has been utterly reliable so far. But I constantly worry about that big plastic clickbox hanging off the side of the frame. Even though there is a protective steel bar to shield it, it is just a matter of time before something smacks it. Or it gets cold and the plastic housing cracks. Or it just wears out. I set up an Ebay saved search for the clickbox to see if I could find a backup, and have not had a hit in about 2 months. I will feel better when I know I have the spare clickbox ready to go. I got a good deal on it NOS, so I am not out too much money if I have to go in another direction. But if I had to do it again, I would have gone with the Nexus.

jim

HelluvaStella

Thanks. After speaking with the customer service rep from the place I ordered it from, I bagged the SRAM and switched to a Shimano Nexus Inter-8 with roller brake. He gave me the same price and I'll get everything on Friday. So sweet to get all the parts for a wheelbuild session in time for the weekend. I tried to calculate the required spoke lengths for the new hub (I already bought them thinking I'd have the SRAM), hopefully they'll be ok. SpokeCalc told me they would be 1mm off.

jgedwa

Great. I really like the idea of the SRAM hub, but other than easier wheel changes, I am not sure what advantage they have. I would guess that spokes that are 1mm too long will not be a problem. Make some sort of offering to the wheelbuilding gods before you start so that they might show you mercy.

jim

Batavus

That nexus 8 is definately not tandem spec'd. You will ride it into the ground in no time. The Sram S-7 is definately more reliable, but the older, Sachs made, spectro 7 hub is much stronger. When Sram took over Sachs, the hubs became of a more questionable quality, except for the Cargo spec'd P-5, which still has the older, stronger internals.

HelluvaStella

My search for an appropriate internally geared hub had these requirements:
5 or more speeds
Not coaster brake (or no brake i.e. rim brake compatible) so that left drum or roller brake
The P-5 is not available with drum brake as far as I could find. The S7 was difficult to find in stock. Someone from the Utility Bikes forum suggested ebikestop, which I did not find during my initial search for the S7. Even after being guided to ebikestop, I saw they have the highest prices and anyway I didn't call to see if they had the right one in stock.

I respect your opinion regarding the non-tandem rating of the Inter-8, but none of these hubs are tandem rated. Going by that, and the type of riding that it will be used for (infrequent picnic rides in the park, very easy cruising, mild inclines), I decided on the Shimano. In addition, I may want to put this hub on a standard bike in the future if it doesn't get used too extensively in tandem duty.

It may be a stretch Batavus, but do you know of a source for the older Sachs 7 speed hub? I see you're across the ocean, would it be prohibitively expensive to get one to the States from Europe, taking into account exchange rates and shipping costs? As an example, I spent $250 for the Shimano hub, roller brake and shifter/brake lever assembly. So somewhere near 175 EUR.

Thanks for your input,
Luke

wroomwroomoops

This is in Germany, but the seller might ship to USA if you ask them nicely. It's new and comes with all the other necessary bits and pieces.

wroomwroomoops

The question is, would a SPECTRO s7 be a suitable hub gear for a tandem? I am not sure, it might not be robust enough. SRAM makes a version of the P5 which is, however, designed for tandems. Check it out.

wroomwroomoops

My ex-GF and I used to tandem a lot and never switched gears, although we have a fairly hilly environment. She loved it, as for a stoker it's challenging to follow the speed shifting of the capitan, sometimes. And since we are both in good shape, going with singlespeed wasn't an issue, especially after a while. Singlespeed is definitely the strongest kind of rear hub you can imagine.

Maybe you could consider this option?

Batavus

I think I was overreacting,

if you are going to use the tandem for light recreational use, it will probably be fine. It's just that at the shop where I work we have tandem riders who pound the living daylight out of their tandems and sometimes manage to ruin a 48 spoke tandem hub.

I come across the older Sachs hub sometimes. I could pick it up used for probably 50 euros. But these were fitted with either a drum brake, no brake or coaster brake. Drum brakes suck, even on normal bikes and you don't want a coaster brake, which leaves the brakeless version and that one is a bit harder to find.

The new Sram can be bought with Sram's updated drumbrake: i-brake, which is a definate improvement, but they have had to recall a huge batch of them due to faulty friction pads which caused them to squeek.

On top of that they have had to recall a different batch of i-brakes to replace the bolts that were used to attach the brake drum to the hub. In addition, they also have had to recall the Force road brake calipers for a faulty bolt or nut or something. Sram definately have a problem with quality control, they need to step up their game if they are going to compete seriously with shimano.



Ps. Shimano rollerbrakes are very good indeed. Oh and shipping would be around 23 euros to the US

HelluvaStella

Based partly on your reply, I'll stick with the Shimano. It's already ordered, so if nothing else I'll build it up, try it out on the tandem and see how it goes. Barring any catastophic failure, I'll have a fine wheel built up on a usefull multi-speed hub that can be the basis of some other bike in the future. You say the roller brake is very good, that's what I'm after. The frame has no rear brake bridge since it was made for a single speed coaster rear, so that leaves me with the choices of drum/roller or coaster. Being the first tandem we have, I'd rather be able to backpedal as with a freewheel rather than be limited by the mechanics of a coaster.


I appreciate your replies, they've added to my growing understanding of a subject I've always been interested in. I love the low maintenance of an internally geared system and I hope to expand my fleet of them in the future.

mtnbiker4791

etting the multi speed sram hubs in the US is a difficult one as tey dont import much if any at all because there is not a big calling for them here. They are much more popular in Europe where they have no problem selling through them quickly. I was helping work with one of the africa bike projects and we talked to one of the higher ups at SRAM and were able to get them to ship one from Europe for us, a P5 non cargo we wanted the cargo but they didnt have any in stock anywhere.

wroomwroomoops

I agree. I think they are excellent, even though not the best choice for stopping a tandem - in theory. In practice, they make for great rear brakes even on tandems.

HelluvaStella

Just built it up. Cables to be sized and installed next week. Link to pictures

Batavus

Looking great! I like the combination of modern technology and a classic bike. What rim is that you're using?

HelluvaStella

Thanks! I used Sun Rhyno Lite rims front and rear. Once the cables are fitted I want to get it out to take some proper pictures in the sunlight. Soon...