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Old 11-20-09, 05:46 PM   #1
otakux
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Is it normal to for rim to hit ground when going over train tracks?

Hi lately I have been finding myself going over train tracks and hearing the rim hit the ground, and today as i was leaving the driveway i heard my rim hit the ground again as there was a small gap from the drive way to the road, and I got a flat. anyone have suggestions how i should fix this?
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Old 11-20-09, 05:50 PM   #2
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Air up the tires to Max PSI before every ride.
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Old 11-20-09, 06:13 PM   #3
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Well, not necessarily Max PSI, but some pressure a lot higher than you're using. We could help more if we knew
  1. tire size/width
  2. your weight
  3. current tire pressure


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Old 11-20-09, 06:19 PM   #4
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[QUOTE=DMF;10058166]Well, not necessarily Max PSI, but some pressure a lot higher than you're using.


Air them up to Max PSI Everyday.
I do and have never had his problem in 26,000 miles.
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Old 11-20-09, 06:22 PM   #5
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Your rims must be too big.
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Old 11-20-09, 07:17 PM   #6
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  1. tire size/width 700 x 23c
  2. weight 130
  3. duno
I guess i should just pump my tires up more :[
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Old 11-20-09, 07:19 PM   #7
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Air them up to Max PSI Everyday.
I do and have never had his problem in 26,000 miles.
You don't need to use Max PSI. You should use a pressure dictated by your weight and tire width. A lower pressure is often more efficient, to say nothing of the comfort level.

But you're right on airing up before every ride.
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Old 11-20-09, 07:22 PM   #8
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  1. tire size/width 700 x 23c
  2. weight 130
  3. duno
I guess i should just pump my tires up more :[
You're pretty light. I'd say 90 psi is all you need - maybe less. But you must pump up before every ride. A bike tire can lose 5-10 psi overnight.
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Old 11-20-09, 07:22 PM   #9
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You need Max PSI on RR Tracks if you use 700 x 23 tires.

RR Track riding is neither comfort or efficient riding.
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Old 11-20-09, 07:25 PM   #10
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Okay, have it your way.
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Old 11-20-09, 07:31 PM   #11
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You don't need to use Max PSI. You should use a pressure dictated by your weight and tire width. A lower pressure is often more efficient, to say nothing of the comfort level.

But you're right on airing up before every ride.
-10

NO. Lower pressure is absolutely not more efficient with the tires OP says he has.
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Old 11-20-09, 07:46 PM   #12
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<sigh> Please do some research.

Pressure higher than optimum drops rolling resistance a little, but that applies only to a smooth surface. On a real-world surface it causes the tire to bounce, wasting energy as the bike is lifted, and increasing rolling resistance when it comes back down.

http://sheldonbrown.com/tires.html#pressure (though there are better overviews in threads here).
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Old 11-20-09, 09:21 PM   #13
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Originally Posted by otakux View Post
  1. tire size/width 700 x 23c
  2. weight 130
  3. duno
I guess i should just pump my tires up more :[
At your weight I'd say 100 psi in the front and 110 psi in the rear. Pump them up before each ride. Road bike tires lose pressure fairly fast, maybe 10 psi in the first 24 hours. Check to see that your rims are still round.

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Old 11-20-09, 09:25 PM   #14
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Try some tires with more volume?
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Old 11-20-09, 09:27 PM   #15
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Fred's wrong. The tire pressure depends on the total vehical weight. It is higher for the rear than the front. Try 100 psi on the rear and 80psi on the front.
Here's the article from Adventure Cycling. http://www.adventurecycling.org/reso...SIRX_Heine.pdf
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Old 11-20-09, 09:33 PM   #16
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The people that advise you to run low tire pressures are interested in selling you more tires and tubes.
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Old 11-20-09, 10:14 PM   #17
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You're pretty light. I'd say 90 psi is all you need - maybe less. But you must pump up before every ride. A bike tire can lose 5-10 psi overnight.
5-10psi overnight? Holy cow. I'd be questioning the quality of my valves if I were losing that much in 8 hours.
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Old 11-21-09, 12:50 AM   #18
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Learn better technique: Lift your body up off the saddle while crossing bumps and loosen up your joints. Unlike running at max PSI regardless of conditions , this has the benefit of hurting you less, not more.

23mm tires have hardly any air volume in them in relation to the surface area of the tube. Given typical rates of diffusion across the tube, 10psi loss in a day sounds quite normal.
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Old 11-21-09, 12:57 AM   #19
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See what is coming and get ready for it do a small bunny hop if needed.....Plus make sure your tires are at max or close to max PSI.
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Old 11-21-09, 01:09 AM   #20
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When you say you're crossing rr tracks, there can be good places and bad places to cross...are you crossing bare tracks, or where the pavement makes for a nearly smooth surface, or what? In any case, just sounds like you need sufficient air pressure...checking frequently is good.
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Old 11-21-09, 01:12 AM   #21
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Originally Posted by otakux View Post
  1. tire size/width 700 x 23c
  2. weight 130
  3. duno
I guess i should just pump my tires up more :[
do you have a floor pump with gauge?
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Old 11-21-09, 01:17 AM   #22
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do you have a floor pump with gauge?
Nope, Going to buy one this weekend.
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Old 11-21-09, 09:36 AM   #23
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The people that advise you to run low tire pressures are interested in selling you more tires and tubes.
+1

Or just clueless.

**Why am I even responding to this useless thread? Seriously...low pressure is best?? Most insane thread I've come across.

What's next?
-Lower the seat, so that your legs don't have to go up and down as far, so you get better pedaling?
-Loose brakes, so that you have to pull the brake lever harder, which exercises your hand muscles better?
-Loosen the spokes, so that the rim can 'flex' with the terrain of the road?

-
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Old 11-21-09, 09:41 AM   #24
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Originally Posted by 10 Wheels View Post
Air up the tires to Max PSI before every ride.
Quote:
Originally Posted by 10 Wheels View Post
You need Max PSI on RR Tracks if you use 700 x 23 tires.

RR Track riding is neither comfort or efficient riding.
Quote:
Originally Posted by 10 Wheels View Post
The people that advise you to run low tire pressures are interested in selling you more tires and tubes.
Incorrect.
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Old 11-21-09, 09:46 AM   #25
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+1

Or just clueless.

**Why am I even responding to this useless thread? Seriously...low pressure is best?? Most insane thread I've come across.

What's next?
-Lower the seat, so that your legs don't have to go up and down as far, so you get better pedaling?
-Loose brakes, so that you have to pull the brake lever harder, which exercises your hand muscles better?
-Loosen the spokes, so that the rim can 'flex' with the terrain of the road?

-
If this is the most insane thread you've read then welcome to BF. It won't be your last. And do some research before you call others clueless.

BTW, nobody said low pressure is 'best'.
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