"David Adams" <[email hidden]> wrote in message
"]news:[email hidden]...
Quoted message said:We bought a cheap tandem 6 months ago and in that time we have destroyed
two
Quoted message said:rear tyres due (I think) to the rim overheating on descent.
The bike only has V brakes front and back although there seems to be a spacer on the rear axle
where another brake could be fitted. This would be what I understand is called a drag brake.
The question is - What do I fit?? disc or drum seem to be the obvious choices -- can anyone shed
some light on the pros and cans??
1) Read the archives of tandem@hobbes, accessible via search.bikelist.orgsearch.bikelist.orgOpen ↗. It's a frequently
discussed question.
2) Look at the tandem club discussion board for the same question. www.tandem-club.org.uk.
Summary : Tandems are really hard on drag brakes. Coming down a hill with the brake continuously on
to keep your speed down will generate a _lot_ of heat. Pretty much the only brake that can hack this
is the Arai drum brake.
Avid mechanical discs are not warranted for this use, as they've got plastic bits which could melt.
People have melted the pipes on hydraulic systems.
If you've got a suitable hub (left hand side is threaded), then the arai is pretty easy to fit. If
the frame doesn't have suitable brazeons for the reaction arm, you'll need some form of clamp
arrangement, but this is fairly common.
Your next question is who controls the drag brake. Some say captain, some say stoker. Front
advocates point out that having somebody in charge of a brake who can't see where they are going is
a bad idea, as you could accidentally lock up at an inopportune moment. The traditional cabling for
this is two rims off one hand, and drum off the other. Some rear advocates say the drag brake isn't
strong enough to lock the wheel up anyway, so there's no worry about control. (This is me - I've got
rim brakes for stopping, the drag is just to make hills easier on my hands/tyres).
(If your frame has suitable braze ons, you could try a disc. You can get threaded adaptors to mount
a disc rotor onto a tandem hub where the drum goes. But in this case you would probably want captain
control, as it would be quite easy to lock the wheel with a disk. But I guess since it was a cheap
tandem there won't be any mounts, so this option is really out).
If you don't have a suitable hub (threaded) then don't forget to budget for a new back wheel.
cheers, clive