Author Topic: Orbit Superlight  (Read 1498 times)

Orbit Superlight
« on: March 05, 2017, 01:58:59 am »
Dear YACF Tandem folk -

We have an Orbit tandem that we bought off of ebay a couple of winters ago for a few quid, and am now thinking about upgrading it. The model is unknown, the frame is unpainted aluminium with Superlight stamped near the headset. It has 8 speed XT and 26" Alex dh22's on XT hubs. My 8 year old daughter loves to ride stoker and now wants to do some time trials and longer faster routes. The rear set up appears to allow both 26" and 700c wheels (it has the option of V, canti or disc brakes). So my question is - would we benefit from converting to 700c? I already have a carbon fork and Alex G6000 that would work on the front, and I could use the rear hub (36h) to build up a 700c rear wheel on another G6000 rim (on the assumption that the rear needs to be 135mm?). Thanks in advance for any suggestions.

Re: Orbit Superlight
« Reply #1 on: March 05, 2017, 04:03:07 pm »
Orbit tandems are sold by JD Tandems in Gargrave, Lancashire (www.tandems.co.uk) I'm sure if you call them, they will happily give you any information you need on your particular tandem.


So my question is - would we benefit from converting to 700c?

Some folks believe 700c wheels are inherently faster, others believe the contrary. My view is that the sort of tyre that you use probably makes a greater difference in rolling resistance than the size of the rim.

(on the assumption that the rear needs to be 135mm?)

Are you sure? Most recent tandems are 145mm wide, not 135mm.

Re: Orbit Superlight
« Reply #2 on: March 06, 2017, 02:25:52 pm »
I don't know if this helps, but long ago I had a touring bike built up on 26" wheels (back then there was a brief fashion for this sort of thing). After a number of comparative tests with its predecessor (same material and geometry, but 700c), including a few club time trials, I decided it was about 2% slower overall. Acceleration was better, but I think it lacked the flywheel effect that the larger rim diameter gave.

For a tandem, though, I'm not sure that it will make so much difference. I must admit that I've only ridden tandems with 26" wheels, so I haven't got any direct comparison, but the extra weight will compensate somewhat for the reduced angular momentum of the wheels, and with my 8 year old on the back I need every bit of help I can get with acceleration.

For a time trial 2% is important, but just for a fast ride it probably isn't going to make a noticeable difference. I probably wouldn't bother changing the wheels, as it would be a lot of work for little gain. My son is a bit of a speed freak, and I find the best way to satisfy him is to descend one of our local hills.

clarion

  • Tyke
Re: Orbit Superlight
« Reply #3 on: March 06, 2017, 04:43:56 pm »
I've ridden tandems with 20", 26", and 700c wheels, and they suit different purposes.  I would say that for a tandem, it doesn't make as much difference as tyre choice etc
Getting there...

Re: Orbit Superlight
« Reply #4 on: March 15, 2017, 01:59:21 pm »
Thanks for the replies. The rear hub is 135mm, so for £50 I can get a 700c rear wheel (and use existing parts to convert the front to 700c with carbon forks with some 28mm durano's i have). Or use the same £50 to buy a pair of durano's or gators for the 26" wheels?

Re: Orbit Superlight
« Reply #5 on: March 16, 2017, 04:29:00 pm »
Our first tandem has a 135, actaully it may even be a 130 (it's Sora branded) hub and it has been fine even with some off roading.  We don't do heavy though.

Re: Orbit Superlight
« Reply #6 on: May 05, 2017, 12:24:27 pm »
Here's an update (if anyone is even remotely interested?!) -

I got some 26" durano tyres (28mm front, 35mm rear) dirt cheap so fitted them to the wheels and installed the carbon forks and front 105 brake (also installed a new headset I had lying around). I then fitted some drops and and some 8 speed STI shifters and new cables. It looks goods, rides really nicely (need a shorter stem though), and is smooth and fast. The only issue is that the front crank arm now sits only 7cm above the ground; as opposed to around 11-12cm before, and I have to be careful over any bumps or on the trails that i don't catch it. So maybe I will have to make one final change to the 700's after all?

Will take a photo later.

Re: Orbit Superlight
« Reply #7 on: May 07, 2017, 10:48:34 am »
How do I add a photo?

Re: Orbit Superlight
« Reply #8 on: May 10, 2017, 02:50:57 pm »