Home made MTB tandem - It made it to the pub! - Pics page 4

[legrandefromage]

you need some sort of eccentric BB to get the chain tension right

 

[hirosawa]

Good work!

Some tandems just have a roller on an adjustable mount to keep chain tension, easy to fabricate and a lot cheaper than an EBB. Possibly not good enough for off road use though?

 

[legrandefromage]

Good work!

Some tandems just have a roller on an adjustable mount to keep chain tension, easy to fabricate and a lot cheaper than an EBB. Possibly not good enough for off road use though?

Need to construct some sort of bracket and keep it away from feet when pedaling

Another home brew:

http://dirkb.dnsalias.net/tandem.html

 

[s1monf]

Chain tensioner

Yeah, I was thinking of making something similar with a jockey wheel under the chain on a pivoting arm so that I can attach a spring.
Sheldon suggested putting a floating bigger chain ring in the middle so I just set it up as pictured and snapped the sync chain within 200 yards!

 

[bonkersbuilder]

nice job !!

I would give a half link chain a go they it would take some slack out and they are strong enough for bmx racing so should be less liable to snap.

on the tensioner front pashley trikes all come with a spring loaded tensioner arm that should be easy enough to source or copy.

 

[MiniNinjaRob]

Go retro with a DCD!!

 

[MikeD]

I was going to suggest the floating chainring, but I'll keep quiet about that now

Some sort of BB-mounted roller guide on the front chainset?

If it's only cost £26 so far you could sell the tyres and be into profit

 

[dinger]

Isn't the rear top tube lengrh going to be 6-8 inches shorter than it should be to mount the bars behind where the headtube was?

 

[MikeD]

Aye, ideally you'd extend the back end like the one LGF posted

 

[s1monf]

Length

The top tube length on the rear was pretty long in the first instance and whilst I,ve probably lost 150mm over conventional bars, it feels pretty comfy.
With a layback post and a long railed saddle the riding position feels spot on.
Much longer and I'd be spending all day looking at a pair of buttocks.

The weight, by the way, with the components fitted is only 36.5lb! :shock: