Thursday, September 13, 2007

Path Racer Trial

As noted in the previous post, yesterday was trial day for the Path Racer. So how did it go? Generally quite well.

It's hard to over emphasize how big a 700Cx35x38 tire is. Someone who had seen the tires on the shelf, felt the need to comment on their size after seeing them on the bike. They aren't as wide as an old Schwinn, but they're tall. And with my weight on the bike, the bottom squishes way out. So much so, that I went back to the Berto chart of suggested pressure for tire size and bike/rider weight. All was correct so I pushed off.

As I've gotten older, my hands have gotten more and more sensitive while riding - to the point I can now claim to have Cyclists Palsey. The tingly/numbness can last for hours after a ride. On the black track bike (which can be seen at www.CyclesNoir.com), I've switched to upright bars, and then had to add Oury grips to give me a cushioned perch. Otherwise, a 30 minute ride left my hands tingly for a couple of hours.

On the PR (Path Racer) shake down ride, I had some stiff Nitto drop bars. They weren't taped, but had a set of Oury's on the bottom for just-in-case. Generally, the bars are a bit slippery without tape and require a tight grip which can lead to cramping and exacerbate Cyclists Palsey. After two hours, my hands were fine. I felt like a young man again.

The PR's frame is 531 standard gauge in a 1.0/0.7/1.0 profile - so it's not light. And, while it isn't the stiffest frame I've ever ridden, it's not a slouch either. Those heavy wall tubes do their job. Combining these tubes with the tires (which I estimate at between 700 and 800 grams each) and you end up with a pretty heavy bike.

The heavy tires are felt under acceleration. The PR doesn't sprint as well as my road bike - not that I expected it to. But otherwise, it doesn't feel heavy under the saddle. The tires roll pretty well, considering that they aren't performance tires. Coasting isn't a problem, nor is maintaining a steady speed. And in some circumstances, its possible to go a little faster than usual because of the cushioning provided by the tires. So far - so good.

Handling is interesting - which isn't bad, just not quite what I expected. The tires provide a significant amount of stability. It can change direction quickly, that's not an issue, but it's as if the steering has a dampener in many circumstances. I need to decide whether to further rake the fork (and reduce trail), or leave it with the assumption that the next set of tires will be a little smaller/lighter.

Rolling down the road, the PR feels like its on rails. And this impression rises quickly with speed. Nonetheless, it's easy to turn the bars and this registers as an immediate reaction from the bike. Going around corners, the size of tire makes everything seem very planted. Lean angles that normally would feel 'at the limit' don't. But it is possible to steer to a tighter or looser line. On the other hand, leaning the bike takes more effort. Some of this may be due to the overall weight, and some to the increased centrifugal force from the big tires. The effect isn't unpleasent, just different.

Climbing was also interesting. I consider low-speed climbs to be a good test of effective bicycle geometries. Poor designs, tend to wander all over the road. The want to fall off of their line, and need a little burst of speed to be pointed back uphill. The path racer doesn't do this at all - so good. But, when standing, as the bike swings back and forth, the front wheel steers from side to side, about six inches either way from the center line. There is no loss of control - the wheel returns to straight ahead easily as the bike returns to vertical. But it doesn't want to track a perfectly straight line while standing. It may be that, with a loaded handlebar bag, this behavior will be dampened out. Time will tell.

Meanwhile, I have to mount that rear brake bridge and a couple of rear fender fittings, give it a final file and sand everything down. Tuesday evening it's scheduled to go to Duane's for some new paint. I'm still thinking about colors - so you'll just have to wait and see what we come up with.

Cheers

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