Tandems of the forum

Just the ticket. Look really smart. There’s even a bit of a colour match there.
New page fail - rollercam look good @Skülly

Funnily enough I love the brake so much I've been rethinking repaint colour.

Use a pair of Mt200s on our thorn...

Its personal preference, experience and how your going to ride the bike.

I should get some photos of our John Atkins/Lee Cooper one done soon.

htbry?

Hi all
Want to ask a general question about crossover cranks... what’s the wisdom of making these have generally small chainrings? The stronglight Left pair of cranks I’m re-using have 34t rings, the wear is pretty heavy and I was thinking about using much bigger rings. Is it a strength thing, i.e. bigger rings more likely to fail under the various combined forces of two riders?

what’s the wisdom of making these have generally small chainrings?

There's no wisdom, just tradition and a desire to save a little money and weight. The primary drive rings, whether crossover or straight through, take no more load than those on a solo.

The limit is going to be chainstay clearance, up to that point going bigger is a good thing for smoother drive and slower wear.

Thanks. Of course, stays clearance is something to bear in mind, I was excited to see some 52s in the obselete PCD of the cranks I have, but needing a mahoosive BB spindle and large Q factor for the stoker is probably worth avoiding.

needing a mahoosive BB spindle and large Q factor

In a symmetrical set up, there should be no effect on spindle length and Q from using primary drive rings the same size as your largest final drive ring.

Ta again.

Picked this up today. Very good price, fits me and the kid and in great condition.

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extremely rad!

110% wup wup!

Just picked this up for me and my 9yr old daughter, had a quick check over and all working well.

As it has disc mounts I was thinking of building up the dynamo disc hub I have, this is 36h but the wheel on there is 48 spokes- is the 48 overkill or will the front wheel fold with only 36 spokes?

(noob to the joys of tandeming)

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36h will be fine!

is the 48 overkill

Yes, with a child on the back 36 will be fine for the front, it's barely taking any more load than your solos.

Where's the limit? I'm looking at building new wheels for the Trek posted a bit further up. It's on some tatty 36/36 Linus wheels atm and I was looking at building a set of 36/36 Sputnik/Novatec/Alpine III. 100 kg captain and 35 kg stoker plus a few bags on weekend trips.

We had a crew weight of 170+ on 36/36 Rodi Airline to Shimano hubs with symmetrical lacing. Many racing crews in the ~150kg range use even lower spoke counts without trouble.

The 48H tradition is likely to be a hangover from family camping trips in the days when spokes had nowhere near the fatigue limit of modern stainless steel ones.

I'll go ahead then. And if I just lose weight at the same speed my son gains it, it'll be ok for a while.

Our kiddy back has been on 32h, no issues to date, built for 70kg plus kiddo (currently 14kg) im over 100kg currently and riding it most of the time, but, 2" tyres at 50-60psi

Thanks all, just need a 26in 36h rim now!

Andra 30/40 are bombproof! And cheap.

We have halo white line on a number of bikes, including tandem/two touring bikes, and can’t complain

Wish I’d read all this^ spoke talk before hunting out 48h stuff. Ah well. Done now.

Hello! Found this thread after finding the other one where they restored a Dawes super galaxy and went round France and Spain on it.

My girlfriend and I picked up a second hand super galaxy last year in Bristol, I restored it and fitted it out for touring then we took it round India for a month. It was a pretty special trip, incredible and terrifying in equal measure... we’ve got loads of pics and a diary, we should really get them online some time!

Anyway, I came here to ask about chains. Our timing chain is stretched and worn out and needs replacing, what do you guys go for? I was thinking KMC S1 or Z1, two of them linked together? Cheers

Oh, also one of the front canti brake bosses sheared off the fork when I got it home while taking the brakes off for a clean/service. It must have got stressed/weakened in India or possibly took a knock on the plane. Thank f*ck they didn’t break out there is all I can say!

Suggestions for a fix? Can either get a new fork, get a new boss brazed back on (Argas frame builders in Bristol, about £40-60 I reckon) or just get a nutted caliper brake and fit that as the fork crown is already drilled. We’ve got canti at the back and a drum brake too so I’m not too worried about stopping power