|Fixed gear fiends.......||Len J|
Jun 18, 2003 10:00 AM
|could I ask the pleasure of your response to a query I made on the Fixed gear forum. There does not appear to be much traffic on that board & I would really like the benefit of everyone's experience.
Link to the Questions is:
Thanks In advance
|re: Fixed gear fiends.......||Ray Sachs|
Jun 18, 2003 10:30 AM
|I'll take a shot:
1.) To get to those speeds at those RPMs, you need a pretty low gear. A "standard" fixie used to be about 63-65 gear inches. That would be very slightly high for you, but I wouldn't go much lower.
2.) I've always heard that bigger chainrings and cogs are slightly more efficient, but I don't know if its by enough to matter. I've ridden the same gear with a 42x18 and 40x17 and can't tell a difference.
3.)You generally want the freewheel to be lower for bail out situations and since you can coast on that side. But you can't to to more than a slightly larger cog without using up the range in the horizontal dropouts (I assume you're using horizontals). Usually 2-3 teeth is as much as you can do. You'll probably have to experiment a bit.
4.)Just remember not to coast and all will be well :) And when you do forget (everyone does at some point), try to remember again REALLY REALLY FAST! Seriously, its a revelation, but there's no way to prepare for it other than to just do it. You should probably start off on quiet streets or in a parking lot, but you'll probably want to get out on the road within a few minutes of getting used to clipping in and out. Just go do it and don't worry about it - everyone blows it at some point, but most of us live to tell about it :)
Jun 18, 2003 12:05 PM
|bigger cogs create less friction than smaller cogs. On the surface, one would think thats 'more efficient'. However, when you factor the rotational weight of bigger gears, thats questionable.
Imperceptable gains (or losses), IMO.
Also, 60-65 may be perfect for urban riders or hill riders, but is undergeared for flatlanders or racers.
Best suggestion I can think of toy around gears while you still have a derailluer and cassette (you're not REQUIRED to shift, after all). When you get your FG, just duplicate your preferred gearing.
Last word of advice: patience is a virtue.
|? on friction.||dzrider|
Jun 18, 2003 12:34 PM
|I'd been led to believe that the amount of friction was not changed by the number of teeth on the gears but that larger gears distributed the friction over more teeth resulting in longer wear. Have I been full of $hit all these years?|
Jun 18, 2003 1:07 PM
|The larger the gear the wider the distribution of forces on it. Smaller gears will wear faster than larger ones. This is why many Ti cassettes only use Ti for the larger rings. Steel is used for the smaller gears to increase durability.
I'd say this is only noticeable on really small gears. The difference in wear between a 39 and a 53 would be insignificant IMO. If you have to replace one, due to wear, the other needs to go too.
|re: Fixed gear fiends.......||MShaw|
Jun 19, 2003 9:41 AM
|Looking at point #4, I'm reminded of all the people I've told about racing at the track. Rule #1: Never, Ever, stop pedaling.
If you do stop pedaling, don't lock out your knee. If you let it "collapse" as the crank comes across the top of the stroke, you won't go over the bars. Every once in awhile, I used to forget rule #1... Good thing I can remember not to lock out my knees.
When commuting on my fixed gear in the DC area (from Alexandria to Fairfax) I used to have to go over some pretty good sized hills. I was riding a 42x17 on my fixed gear, and running 39x23 on my road bikes, it always amazed me what you can climb in a pretty good sized gear if you don't have a choice.
|re: Fixed gear fiends.......||KEN2|
Jun 18, 2003 11:05 AM
|I like to spin too (92-96), and I prefer a 72" gear, which on my fixie is a 46x17. I admit that I usually choose the flatter routes, because rolling hills are not great with this gear, but then my experience is they're just not great with any FG since you need a reasonable gear to climb, which gets you all spun out descending. With the 72" I've spun to around 150 rpm downhill, which translates into 32 mph.
You should go 1-2 teeth bigger for the freewheel... I agree, though, that you may never actually use the freewheel once you ride fixed. One thing that doesn't seem to get much attention is the efficiency of FG--not just the friction savings over derailleur equipment, which I think is minimal, but rather the fact that the momentum of the fixed drive wheel propels you along, returning energy--there are no dead spots. I can easily average faster on my FG than my road bike.
Biggest problem I have had fixed riding is not cornering, etc. but rather the more "unconscious" stuff: adjusting shorts, and crossing RR tracks. On more than one occasion I've tried to stop pedaling for one of those and gotten a rude kick in the butt from the bike!
|Posted my $.02 worth (nm)||Humma Hah|
Jun 18, 2003 1:09 PM
|Thanks All! nm||Len J|
Jun 19, 2003 3:19 AM