Field Cycles custom disc road build

I have now had an initial geometry drawing back from Harry with some comments from him (below):

1. Tubing sizes will be: Down tube - 34.9 (oversized but not massive), Top tube 31.8, Seat tube is a 28.6 tube with an i.s.p top (Ritchey 25mm set back - Di2 battery to be fitted in the top) and 44 mm i.d head tube.
   
2. Chainstays are the flattened (and shaped a bit more by Field) Dedacciai ones.
   
3. Forks are Enve 43 rake tapered either 1.5” or 1 1/4” (thinking 1 1/4” as they look better with a 44 i.d head tube).
   
4. Stem is an Enve (he has stated that it is 90mm long as the 120mm is too long for the saddle tip - handlebar reach, N.B. there are 3mm of spacers under the stem at present).
   
5. Seatpost top is a Ritchey one with a 25mm set back with a Fabric ALM in the middle of the rails at the correct setback with a seat tube angle of 74.5.
   
6. He will make sure 28mm tyres fit in there (for any (very slight) off roading).
   
   

My thoughts are that it is a good starting point. I'm not entirely convinced on the 90mm stem point though - surely the geometry can be altered to allow for more stem and, accordingly, a little less potential twitchiness?

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