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Singlespeed & Fixed Gear "I still feel that variable gears are only for people over forty-five. Isn't it better to triumph by the strength of your muscles than by the artifice of a derailer? We are getting soft...As for me, give me a fixed gear!"-- Henri Desgrange (31 January 1865 - 16 August 1940)

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Old 01-01-07, 03:29 PM   #1
genericbikedude
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flexing while skidding

I ride a fixed gear bike in the city, and sometimes perform "hockey stops" as a braking method. This involves locking the rear wheel, and throwing the rear end of the bike sideways so that the bike is more or less perpendicular to the momentum vector. Hence the name "hockey stop."

Anyway, when I do this, I notice a lot of flex in the rear end. I can't tell while doing it if its from the stays, the wheel, or maybe the tire. The frame is a Soma Rush, 631 tubes. The wheel is a suzue promax laced 28h 2x, built by me. Tight spokes. The tires change, but are always around 100-140 psi.

Any hits on where the flex might be? Is it an issue of a wheel that is not laterally stiff, or would it be more likely that this is coming from the stays?
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Old 01-01-07, 03:31 PM   #2
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My money's on the wheel.
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Old 01-01-07, 03:33 PM   #3
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My money's on the wheel.
yeah, probably. but what atributes of the wheel would emiminate this? stiffer rim? more spokes? tighter spokes? more crosses?
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Old 01-01-07, 03:37 PM   #4
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You are feeling a combination of everything flexing. Cranks, BB spindle, frame, wheel...that can add up to a lot of flex. Bike parts are not generally built to withstand tons of lateral force, which is what you are exerting on them when hockey stopping.
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Old 01-01-07, 04:25 PM   #5
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i was really hoping that this was a thread about flexing one's muscles whilst skidding. i really was. and i wanted pixx.
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Old 01-01-07, 06:56 PM   #6
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i was really hoping that this was a thread about flexing one's muscles whilst skidding. i really was. and i wanted pixx.
i was severely disappointed as well.
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Old 01-01-07, 07:00 PM   #7
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This is the best I could find.
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Old 01-01-07, 08:50 PM   #8
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i was severely disappointed as well.
I though this was about 'flexin'...gettin' big...manning up...flossin'...etc.
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Old 01-01-07, 10:28 PM   #9
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One thing you could check... stand next to your bike, put the pedal/crank in the 6 o'clock position and push on it with your foot, watch to see how/if the bottom bracket moves latterally (frame flexes) or how/if the wheel flexes, or both. I have a bombproof rear wheel and flexy frame, you can really tell by using this method.
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Old 01-02-07, 12:03 AM   #10
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I ride a 631 Rush. It's not a super-stiff frame. I'm not sure the rear triangle is 631 but I doubt it.

Anyway... umm... best of luck?
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Old 01-02-07, 12:16 AM   #11
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it is probably you wheel more or less I am also surprised you havent destroyed your hub yet doing this a wheel with as little whole count with as little crosses as you have is not necessarily built to withstand the forces your are putting on it neither are anny bicycle wheels

1. learn how to ride your bike properly or put a brake on it you should never skid to stop
you skid to show off skidding is inefficient and expensive

2. this is very expensive because most hubs are not warranteed for anything less than three cross
and should your wheel fly apart like it eventually will imagine the hospital bill

3. have fun and enjoy riding your bike within you skill level and expertise
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Old 01-02-07, 12:19 AM   #12
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631 doesn't come in rear triangle material. Only the main tubes are 631.
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Old 01-02-07, 08:09 AM   #13
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Quote:
Originally Posted by Retem
it is probably you wheel more or less I am also surprised you havent destroyed your hub yet doing this a wheel with as little whole count with as little crosses as you have is not necessarily built to withstand the forces your are putting on it neither are anny bicycle wheels

1. learn how to ride your bike properly or put a brake on it you should never skid to stop
you skid to show off skidding is inefficient and expensive

2. this is very expensive because most hubs are not warranteed for anything less than three cross
and should your wheel fly apart like it eventually will imagine the hospital bill

3. have fun and enjoy riding your bike within you skill level and expertise
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Old 01-02-07, 08:14 AM   #14
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I get this sometimes also. Only when I throw hockey stops also. I'm attributing it to the rear wheel just flexing a bite. I built my wheels myself, so I'm sure they could be done better by a pro. I'm planning on getting my next set built by a pro and seeing if this still occurs.
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Old 01-02-07, 08:16 AM   #15
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Here's Andy flexing just for you
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Old 01-02-07, 08:18 AM   #16
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by the way I'm on a 32 hole rim laced 3x.
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Old 01-03-07, 03:21 AM   #17
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Quote:
Originally Posted by killsurfcity
yeah I know I am a geek but I know what I am talking about
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