Dawes Impulse, Reynolds 531, Shimergo

Here's a comfortable ride that I recently acquired via an internet sale:

And here is what it looked like on purchase, before I sorted out the handlebars, changed the front wheel, and fettled the brakes:

Here are extracts from 1990 Dawes catalogue:

And some blurb and data:

Rest of the catalogue data:

In my sample, it seems that quite a few parts have been changed. However, I think the original chainset Exage Biopace 52/42T 170 and brake levers were still on. The gearing was a bit insane, with a Shimano Uniglide 6 speed hub, and lowest gear of 42-21T (53"). But, it shifted well. So, I changed the bottom bracket from the cone and axle cotterless to a sealed cartridge Shimano 110mm unit, and the chainset to a 46/36T 175. This gave much more manageable gears with a low of 36-21T (45").

And here's a photo of it today, with the new chainset, saddle, seatpost, tyres and the as purchased front wheel back on:

Next step is to get rid of the DT shifters in the most convenient way possible. I love DT shifters, but one has to admit that bar-mounted shifters are better. The rims are grey anodised Mavic-MA40 and are virtually new - definitely not what was on the machine as shipped by Dawes. These rims have been rather nicely laced on to decent refurbed hubs - Campagnolo in front and Shimano FH-RM50 ND (6 spd Uniglide) at rear. Not only that, the 6 speed system is shifting well, so I'm minded to leave it as is.

I measured the pitch (distance between sprocket centres) as best I can, and made it 5.5mm. Consulting references on Shimergo - btw, I'm really annoyed with the CTC and their shoddy reproduction of Chris Juden's article on the subject - tables are chopped-up/wrong/missing! - I'm minded to try simply fitting second hand Campagnolo 8 speed Ergo shifters. The undoctored chart (Table 4) indicates that with the 'hubbub' rear mech clamp tweak, there would be ~0.03mm discrepancy in cog pitch, so it ought to work.  I have some DT stops already in my bike bits. The 1990s 8 speed Campagnolo shifters that I've seen for sale often have splits in the brake hoods. I'll probably have to get new hoods, but that's not a big deal. Even if I'd not bothered with a Shimergo mod, I'd have had to buy replacements for the current tatty and discoloured gummy ones. They are supposed to be white, but they've disintegrated to beige.

However, the rear mech does not appear to have a hubbub-able cable clamp! That said, old style Campagnolo 9 speed shifters give a pitch of 5.49mm, whereas the new style ones of same speed provide 5.26mm. This is going to be interesting...

Excited to try this and blog about it later.