|   result of reducing rotational weight? | puppet
Apr 2, 2002 5:43 PM | | I think I went over-kill on my wheelset and tires. I can probably drop 2 pounds by switching wheelsets and using lighter tires and tubes.
Where would I notice improved performance? I do mostly XC with lots of climbs and I've felt very sluggish. It's probably just me - but the sluggish feeling has come at the same time that I tried the new (heavier) setup.
Thanks |
| it depends............. | heff®
Apr 2, 2002 6:00 PM | | .......on where the weight is located on the wheel.
In general, a heavier rim is harder to push than a light one, as the added mass is farther out on the wheel. On the other hand, a heavy hub isn't much different than a really light one, other than on the scale.
It also depends on your riding. For my terrain, style (or lack of), and weight, I run rather heavy wheels (Rhyno Lites/XT disk hubs), but switch to lighter tires when the need arises. I'd much rather have the mild potential of a pinch flat than the much greater potential of a damaged rim or hub. If you don't have one solid rock garden for a trail, though, and weigh less than me (not hard to do, I go 235 now), a lighter rim will definitely make a difference.
What wheels and tires do you have now?
heff® |
| my setup | puppet
Apr 3, 2002 4:31 AM | | I'm 185 pounds and I'm on Rynolites w/XT disc hubs. I'm using 2.4 motoraptors front and rear . . . about 800 grams each.
Thanks |
| This is my exact set up | Mr Magoo
Apr 3, 2002 5:50 AM | | Rolls over stuff like a monster truck, but stalls a bit climbing the steeps. These tires are about 780 grams. Try a lighter set. I use serfas which are about 550 grams. feels like helium going over hops and jumps, quick accelerations. Also find a steep climb that you can just barely make or have to push some. I always climb better here than on the bigger tires. Then go back to the big tires and climb the same spot. You'll probably stall lower on the hill.
Honestly, I favor sure footed over light. I end up going even heavier than moto raptors with 1000 gram kujos. Tires are always a compromise. |
| re: result of reducing rotational weight? | BCRider
Apr 2, 2002 7:38 PM | | Heavy wheels will only be noticed during acceleration. If you vary your speed a lot during the climbs then you'll tend to feel this more.
More likely is that if you've gone to some jumping type extra wide tires you're just feeling the drag of all that tread.
Certainly loosing a couple of pounds will make a difference but by itself a couple of pounds doesn't add up to much when you consider the weight of the bike and you put together. |
| re: result of reducing rotational weight? | Yeti_Rider
Apr 2, 2002 8:02 PM | | Rotational weight is 1 1/2 times more than stationary weight. And, the further it is from the center of rotation then the harder it is to get moving. So, losing a pound off your wheels will be like losing 1 1/2 pounds in another area of the bike. Heavier wheels will be harder to accelerate, but once they are up to speed they will actually want to stay rotating more easily than lighter ones which will aid in cornering.
Michael |
| re: result of reducing rotational weight? | zacho
Apr 3, 2002 4:18 AM | | it has to do with something called a moment of inertia...which is basically a property of a rotating body that describes the distribution of mass about the rotational axis...basically...the weight is counted once...and the distance is squared...so it's better to lose 1 gram off your rims...than 4 off your cassette...remember that next time you got to decide whether or not to spring for that ti cassette in the xtr line :-) ... light rims accelerate...but heavier rims are easier to keep going...if you do lots of climbing...i'd get some light weight wheels...if you were doing time trials on the road or something like that where you didn't have to worry about variation in speed...heavier rims might make a dif...but for xc...the lighter the better
zach |
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