Wednesday 7 November 2012

Genesis Equilibrium Build Log Part 1: The Frame

Genesis Bikes' Equilibrium frame has earned a great reputation. They struck a happy chord with this one, producing by all accounts a comfortable, rewarding and beautifully finished frameset. I had the good fortune to pick up a new example at a bargain price. My intention is to build it up as a commuter as cheaply as possible. That means using as many of my own bits and bobs that I have lying around. So there's a good chance it will end up a bit weird!
This is nominally a 56cm frame, but the Genesis website specifies seat tube (c-t) 550. It has a relatively short effective top tube of 558, suggesting it will have an upright riding position. Head tube is smallish 150, and the seat post is going to be long, given the sloping geometry of the frame. It's made from Reynolds 725 tubing as shown by the classic seat tube sticker (the description of 725 below is from the Reynolds website):

"HEAT-TREATED CHROME-MOLY STEEL
Using an industry standard alloy with mechanical properties similar to our famous 753 brand, Reynolds mandrel butt and heat-treat this alloy so that thinner walls can be used compared to non-heat-treated steels. 725 can be TIG welded and used within our "Designer Select" combinations including 853 and 631 tubes.
Why it works:
UTS: 1080-1280 MPa, density 7.78gm/cc
Based on a 0.3% carbon steel alloy which has been heat-treated and back-tempered for increased ductility. The chromium content promotes hardenability and resistance to oxidation. The molybdenum works in conjunction with the chrome to stabilize the alloy and maintain strength after heat-treatment and in use."
I believe the forks are carbon with alloy steerer (standard headset required, 1 1/8" size), dropouts and brake bushing. Certainly a magnet does not stick to them as it does to the tubing. DT cable guides already fitted, hmm, but am I going single speed? Mudguard eyes (and a paint scratch):
Neat welding and easy on the eye. Seeing the top tube cable ends - reminds me that I always forget to use frame protector cable grommets. Let's see if I remember this time.
BB shell is standard 68. A very sensibly engineered bridge between the chainstays, should make mudguard fitting much easier:
Quite a lot of dust on the frame - needs a spray of frame saver inside and a good clean outside before I start. Seat tube is 28.6 for front mech (if I'm having one, that is!).  
Below, you can see the straight stays and the geometry. Given the short head tube, I'll probably not cut the steerer, but let's see. 
The rear brake bridge (long drop 57) and seat clamp (29.8). Tseat post is 27.2 diameter - I have one of those in my bits box, but will it be long enough?
Stays are quite thin at the tips and the dropouts seem well made. 
Initially I thought that the kink on the inside of the drive side seat stay (below) was a show room dent, but then I looked closely and it's clear that it is deliberate shaping. Quite obvious that the paint was applied after the shaping. The shop told me that other people had queried it, and they'd already clarified with Genesis that this was a deliberate feature. Presumably it's for chain clearance, but some have commented that it is ugly and unnecessary. 
All in all a lovely frame, and I'm feeling quite excited to build her up, as I said, using what I have "in stock". I will need to buy long reach brake calipers though. After the satisfaction and simplicity of my last single speed build, I'm definitely keen to forget completely about gears... 
Well done Genesis. Can't wait to see your new 953 road racing frame for the Madison-Genesis cycling team, Roger Hammond and Co. He's a cyclocrosser too, so I'll be cheering for them!

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