reply to richa
Hi Rich -
- I got the extended slider from the fine people at Cruzbike (support@cruzbike.com). Costs $50+ shipping, and is identical to the standard but is 5 inches longer. Numbered markings go to 17 inches instead of 12.
- With this mod, adjusting it will be a problem, for two reasons:
1) it's very tight (has to be tight to do the job) so adjusting it would be a pain. I got the slipperiest plastic I could find, so it does slide, but not easily.
2) The new slider extends almost all the way down the boom, so you wouldn't be able to shorten the length very much. For my legs, the last visible number is 6.75 inches; at that setting there is only about another 1-2 inches before it hits bottom.
- I got the plastic sheet from our local Tap Plastics shop, which has many kinds of retail plastic. I make a lot of things out of plastic so it's a piece I had sitting around. This is gray polyethylene sheet, 1/16 inch. It's quite flexible and naturally somewhat rounded, so I just cut to length, beveled the top edge so the slider would push it out of the way, and slid it down the boom. I think I paid about $5 for a much larger sheet than I needed for this.
But this is really the beta version. 1/16 inch is too think if it goes around the whole way, so this just goes on one side. That's not ideal, although it does the job. I think this really needs about 1/32 inch all the way around, but it's hard to imagine how one would get that down the boom and still have the slider able to be inserted into it. I think it would take making a (wood?) insert in the slider that made it pointy: then it would push the plastic out to the sides evenly as it went down. Experiment required! Will post results when I get a chance to try this.
One problem is that I can't think of how to measure the inner diameter of the wide boom tube through the narrower opening at the top! That's necessary to do this right. Anyone got an idea of how to do this? How do you (accurately!) measure something thick through a thinner tube?
It's hard to quantify how much difference it makes climbing, but it definitely feels more rigid, so less energy is being lost. I did a few miles of riding with my test setup (earlier post), and get about half the deflection measured before, but the setup is not super-accurate for small deflections so I'm hesitant to say more than "about half". But now it's cold and raining and I need the fairing, so had to remove the test bar. The fairing - attached to the handlebar ends and the BB - is a sensitive if non-quantitative indicator of flex, and it flexes noticeably much less in hill-climbing.
BK