Transmission for an old Tourer

[RELIC]

I have an old Evans Tourer [1973]. The frame and wheels are OK, but the transmission is worn out.

Having spent lots on a Raven, my funds are limited, but I would like to get it back on the road, I understand that many parts may be hard to get. The BB is the square type, but the rear mech is the screw on, rather than the modern one which I think is splined.  To add complication I would like low gearing.  Any idea's?

[Chris Land]

I assume that you mean the rear block, rather than mech, is screw-on.  Is it a 5 speed?  5 and 7 speed screw-on blocks are still available new and are pretty cheap.  You should be able to get a cheap, sealed unit BB for less than £10. Front chain-rings shouldn't be a problem, just work out the diameter of the circle made by joining the centre of all the bolts together and, with the number of arms, a good shop should be able to find you something to fit.  Low gearing won't be a problem, just make sure the chain and derailleur arm are the right length to cope.

[rhebarker]

SJS did a wonderful job on my friend Paul's '80s Raleigh Carlton which needed much the same.  It's given it a new lease of life and it (amazingly) looks incredibly cool.  Give 'em a call - that's if they can get you a slot in the workshop - they looked pretty busy when I called in to collect a new frame lastr weekend.

[daveireland]

I have a 1976 Rory O Brien which I restored some time ago. I remember asking a reputable bike shop about the largest blocks available and was told 13-28 tooth blocks had the largest sprocket for touring. I fitted this and it isn't really low enough for hills in West Cornwall. I've since seen, but cannot remember where I saw 13-32 blocks advertised. Does anyone out there know?

For your Evans, Relic, I would start slowly with a frame blast and respray to see if the frame is still intact before splashing out on a new transmission and maybe consider getting Bob Jackson to widen the space between the rear stays to 135mm (assuming yours, like mine are 125mm, or similar). This would enable you to fit a modern block, although it would also mean a new rear wheel, Oh go on, splash out for Gawd's sake!