Tandems of the forum

Based on the above, I've decided to go for a "Zenith 8/9 Spd Rear Tandem Cassette Hub for Arai - 145mm - 40 Hole" from SJS Cycles. Unfortunately, it's 145mm spaced; - my tandem is 140mm. My intention is to try and fit it in and if not, to get a shop to increase the spacing between the dropouts (according to Sheldon Brown spacing discrepancies of 4mm were standard at the introduction of larger rear cassettes). - Has anyone had any experience 'stretching' rear triangles 5mm to fit hubs (without cold setting)?

I've had a look for 140mm spaced hubs and all are NOS/ aged and take screw-on freewheels which I want to move away from.

@Hovis - It transpires that the rear drum brake was riveted on... I'll send you a PM re your Arai

It looks like your hub was a Maxi-Car one. They're quite sought after if you're into that kinda thing - worth advertising it somewhere!
Check out DCR wheels too, he has a few tandem specific hubs that you can get in different OLDs, as do JD tandems (they'll get the axle machined down). @mdcc_tester will undoubtedly suggest you make a friend of a local machinist and do it yourself!

A Maxi-Car is exactly what it is... With flippin' 9mm nuts which I didn't realise until I tried to fix a puncture with an 8mm spanner, to the tune of: "If you fail to prepare, you prepare to fail"!

The mechanic at the LBS was convinced it was in made in someone's shed.

The Maxi-Car/ Arai fittings look kind of the same so I'm sure the Arai will fit like a glove (!)

It was top of the line in the 50s! Fittings should be identical, and nothing a spare bit of metal, a hacksaw and a file won't fix. I had to do something similar for mine when I got the new hubs.

Hi All,

I know that this isn't a "Current Projects" thread but I thought I'd let you know how this went, since you all provided such useful feedback. Recap - Busted rear axle w. 32-630 wheel size

I originally intended to use the existing rim with a new hub and rear drum brake, so bought a hub from DCR wheels and this screw-on drum brake from SJS: https://www.sjscycles.co.uk/brakes/karasawa-screw-on-tandem-drum-brake-replaces-arai/

My local bike shop then discovered that they had an appropriately spaced, rear tandem wheel with threads to take a screw-on drum brake (and a freehub), so the rear hub went back to DCR wheels (who were very accommodating); - the rim size of the newly discovered wheel was 700cc... However when matched with a 35c tyre, the floor to axle height is exactly the same as the larger front wheel with narrower tyres (35cm). As per the below picture, the stoker's rear calliper brake is a bit tight (but it will be used in the case of a rear drum brake failure only). Finally, I was able to move up from a 6 speed cassette at the back to a 7 speed cassette.

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For those interested, here's a fitted picture of the "Karasawa Screw on Tandem Drum Brake Replaces Arai"; - I was unable to find any others online. It fit perfectly to the existing fittings...

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And a quick picture of the offending 32-630 front and 700cc rear. The stoker's handlebar position is yet to be defined.

My intentions are to have a few pootles around London and see how I feel about the different sized wheels.

As an aside, the LBS has said that they'll have a go machining a new axle so if that's a success I'll attempt to put the old maxi-car back together.

Any comments welcome!

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My grandparents with their 1930s Freddie Grubb tandem in about 1940. My aunt pushing the sidecar.

In about 1992 my brother and i enthusiastically took it apart with the intention of restoring it... but got bored as teenagers do and it's languished in a damp cellar. Until today... will start a thread in current projects!

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As it looks today :/

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Great idea, I look forward to seeing it back to it's former glory!

Oh wow, amazing, looking forward to seeing your thread on this. I'm getting a sidecar for my tandem for my new family member for adventures this summer.

Thanks- it'll be a long slog. I think the only parts missing are the gear controls, but the old resilion cantilevers will be a bit of a headache to sort...

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It will look magnificent when finished.
Post over in the pre 50's thread if you get stuck. Lots of knowledgeable characters.

https://www.lfgss.com/conversations/238801/

Lovely project!

Just saw this, and thought someone should consider buying it... Haven't read description, just liked the pictures...

http://m.ebay.co.uk/itm/Cycle-Gitane-Tandem-Bike-Cycling-15-Speed-Racer-Racing-Bike-/332138159767?hash=item4d54fa1e97%3Ag%3AafwAAOSw%7EAVYsXCT&_trkparms=pageci%253A9962c54b-ff12-11e6-a6e5-74dbd18071f9%257Cparentrq%253A8dbc280a15a0a6a4a6a0d9e5ffe4ec69%257Ciid%253A13

What a bonkers looking drivetrain.

I feel like it would skip and jump around on even little bumps?

Probably yeah. Not sure whats stopping the owner from swapping the two crank arms front and back over and having it like every other tandem in the world?

According to Sheldon:
"Front drive has much to recommend it...It puts less torsional stress on the crossover bottom bracket. A front-drive setup will usually provide better front shifting, and you never have to worry about cross-chaining, since the chain run is so long that all gears may be used without concern for the chain angle "

According to John Allen:
"Stresses on the bottom brackets and the frame are lower than with rear crossover drive"

I haven't done the maths, but I have a feeling that front drive tries to bend the drain pipe less, which would probably be a good thing on a frame with no diagonal tubes.

All sounds good on paper, but then why are the vast majority or tandems set up with the drive being at the rear?

The main disadvantages I can think of are weight and chain slap (perhaps mitigated by the roller set up on the Gitane above, but that leads to more resistance in the system). Any chain suck or dropped chains could become more interesting too with such a long length of chain and two riders to think about.

http://m.ebay.co.uk/itm/Time-Trial-Racing-Tandem-/122362329861?hash=item1c7d5cfb05%3Ag%3Ao2IAAOSwB-1Yqc2b&_trkparms=pageci%253Ac17d733b-03fe-11e7-94b9-74dbd1807e7f%257Cparentrq%253Aadfeb81d15a0a7854620c7ccfffe2712%257Ciid%253A22

Hi, does anybody know of a used track tandem selling in the UK? Finding it hard to get a newer frameset with the geometry we are looking for!

That looks so mega!

Track tandems aren't that easy to come by, unless you get lucky with eBay:
Dolan do a track tandem for £600, which split with your stoker is only £300 each!

We are doing our best to get lucky! We are going with the Dolan to get us going before upgrading unless a better used option shows up. Thanks