Thursday, May 19, 2011


After ordering a new frameset on 14/Feb... I'm about to take delivery. But it's not the frame I ordered. That builder apparently can not even come close to filling their orders. And in fact, stopped taking orders for 2011 in MARCH. I've stubbornly hung on. Waiting. Because I feel the ordered bike is perfect for me. Test riding it was enlightening and elating. But even if it is perfect... it does me no good if I can't get my paws on it. Right now... I'm worried about getting the bike for fall! Delivery slipped from March... then April... then May... now June...

My dealer made me an tempting offer on another frameset. A bike I've don't have the opportunity to test ride. Will the offered frame work for me? All I have is the geometry charts and some engineering knowlege. My goal... to relate frame geometry to handling charachteristics of my Stumpy, Tarmac, the ordered frame, the offered bike, and bikes I test rode but hated.

Yes... I built a spreadsheet...and learned a lot.

Trying to determine the effect of frame dimensions and their effect on handling is difficult. Complicating the process is comparing 26-inch wheeled bikes to 29-inch wheeled bikes. Things like headtube angle don't translate. You have to convert to mm- of trail, a dimension most bike manufacturers don't show in their charts. This is where the spreadsheet came in!

The exercise was worthwhile. I found trail is a excellent predictor of handling. The bikes I liked v. disliked consistantly had similar trail dimensions. Other dimensions weren't consistant. For example: i liked a bike that had an unusually long top tube, and also one that had a unusually short top tube. But both of those bikes shared an equivalent amount of trail. Why don't manufacturers publish this dimension?

The result... I took the offered frame. It's got a trail in my preferred range, a slack HTA, it's light, and I'm getting a great deal on it cost-wise. Some stock photos...

It's a bit of a compromise. It's a bit of risk. But as Lee McCormick puts it... the best bike in the world is the bike you are riding!