How do you pump up high pressure tyres?
10-01-11, 05:55 PM
#26
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The Lezyne CNC pump gauge goes to 220 psi too. I've successfully achieved 200 psi with it and I weigh 160 lbs. The 200 psi was used to pressure test a barbed tube fitting (it held), not for my bike tires.
10-02-11, 09:35 AM
#27
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I also ride at pressures much higher than most. I've found that if I ride at 140 + I have no issues with pinch flats. I weigh 200 Lbs riding 700x23 tires. If he is heavier than that, and or using a skinnier tire, he may need a higher pressure to avoid pinch flats as he alluded to. I also living in the midwest there aern't many switchbacks to be concerned with. Pinch flats however were a constant problem at 120 PSI.
Timtak- I have also found that a suspended seat post helps. I use a Thudbuster ST, it helps to minimize pinch flats too. Since using the Thudbuster and 140 PSI in my tires, I haven't had a pinch flat in MONTHS.
Timtak- I have also found that a suspended seat post helps. I use a Thudbuster ST, it helps to minimize pinch flats too. Since using the Thudbuster and 140 PSI in my tires, I haven't had a pinch flat in MONTHS.
10-02-11, 04:07 PM
#28
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I also ride at pressures much higher than most. I've found that if I ride at 140 + I have no issues with pinch flats. I weigh 200 Lbs riding 700x23 tires. If he is heavier than that, and or using a skinnier tire, he may need a higher pressure to avoid pinch flats as he alluded to. I also living in the midwest there aern't many switchbacks to be concerned with. Pinch flats however were a constant problem at 120 PSI.
Timtak- I have also found that a suspended seat post helps. I use a Thudbuster ST, it helps to minimize pinch flats too. Since using the Thudbuster and 140 PSI in my tires, I haven't had a pinch flat in MONTHS.
Timtak- I have also found that a suspended seat post helps. I use a Thudbuster ST, it helps to minimize pinch flats too. Since using the Thudbuster and 140 PSI in my tires, I haven't had a pinch flat in MONTHS.
10-02-11, 04:22 PM
#29
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When a tire hits a 1" high bump at 20mph, the bike has roughly 1/50th of a second to lift over it, or at least high enough for the rim to clear. That involves serious G-force. The force difference between lifting the bike and rider sitting on the saddle, vs. just the bicycle with the rider using his legs as shock absorbers to let the bike alone rise below him is something close to 10:1.
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An ounce of diagnosis is worth a pound of cure.
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“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
Last edited by FBinNY; 10-02-11 at 09:01 PM.
10-02-11, 08:25 PM
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While tire section and pressure are factors in rim dents or pinch flats, so are road conditions. But by far the biggest factor is rider habits. Some riders never get pinch flats or dented rims, and others always seem to even riding similar equipment on the same roads.
When a tire hits a 1" high bump at 20mph, the bike has roughly 1/50th of a second to lift over it, or at least high ehough for the rim to clear. that involves serious G-force. The difference between lifting the bike and rider sitting on the saddle, vs. just the bicycle with the rider using his legs as shock absorbers to let the bike alone rise below him is something close to 10:1.
When a tire hits a 1" high bump at 20mph, the bike has roughly 1/50th of a second to lift over it, or at least high ehough for the rim to clear. that involves serious G-force. The difference between lifting the bike and rider sitting on the saddle, vs. just the bicycle with the rider using his legs as shock absorbers to let the bike alone rise below him is something close to 10:1.
Last edited by dahut; 10-02-11 at 08:29 PM.
10-02-11, 08:48 PM
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Can you post a picture of the sidewall of the tire? That PSI seems extreme for a tire.
Maybe that's a typo on the website?
Maybe that's a typo on the website?
10-03-11, 03:44 AM
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220psi + Cheap Unbranded Carbon Rims form ebay + Dollar store glue = ?
I don't know what to say. The tyres are at about 150 psi now because it is really difficult to get them up any higher. When they were at 160psi it did not cause me any grief at all. What is the problem? My (almost unbranded) carbon frame seems to smooth out minor bumps pretty well and I ride on pretty smooth roads.
I have never been to a velodrome. I am a novice.
I weigh 160lbs but I don't think that the article that you were so kind as to share is divinely authored. Whatever the article says, I am speaking from my experience - I like the ride at 160 psi. I see no reason why the tyre and rim should explode.
bang.
The tyres (or at least one of them see addendum below), from a very reputable manufacturer, say that they are happy with 220 psi. I am under the impression that higher pressure in these tires reduce the probability of any type of flat. More than one reviewer has suggested that this is the case. There is also less rolling resistance. So all other things being equal - I was thinking of blowing them up to 170psi which is the middle of the range of one of the tires and within the range of the other.
All other things are not equal because the Lenz (thank you :-) and the SKS are alas over 120 USD where I am. The Lenz is even more expensive than the SKS. So....I have not made my purchase yet.
The rims did have a serial number on them when I took the tyres off. I googled the number and it was one of the OEM rims made in China. They look identical to those below, and were listed on the same site but they are lighter (if the guy that sold them to me can be believed).
https://ja.aliexpress.com/product-gs/...olesalers.html
If I new their numbers I'd recommend them because they make me very happy. I'll post a picture if I get time, showing the dollar store glue:-).
Addendum: The guy that sold them to me said that they were S3 tires. I got a flat in one and bought "another" S3 tyre but in fact that they were S33 on the bike at first, so I have a S33 on the back and an S3 on the front. The S33 have a 175psi limit.
Here we go, full disclosure (of my identity, though not the dollar store glue yet)
Tyres on bike
https://www.flickr.com/photos/nihonbu...n/photostream/
The photos from ebay
https://www.flickr.com/photos/nihonbunka/6207226996/
https://www.flickr.com/photos/nihonbunka/6206712279/
I was not keen on the strange floral design but now....It has grown on me.
Thank you for the seat post recommendation. I use an areobar and a very high seat post position. This means that I want to get as much forward offset as I can. Hence I use a USE Sumo seatpost with the saddle at the furthest forward extension it will go. I doubt that I would be able to find a suspended seat post with such a big forward offset. I will try to use my legs when going over bumps. Bang.
Last edited by timtak; 10-03-11 at 04:11 AM. Reason: pictures
10-03-11, 08:35 AM
#33
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What you need is a shock absorber pump they are schrader and a presta to schrader to adapter. A shock pump will go to 300 pounds and it has a gauge. It is possible to blow up a rim at these pressures so it is best to save the higest pressures for tubular rims.
10-03-11, 03:27 PM
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Thank you, but I am not seeing 300psi shock absorber pumps advertised/for sale. Can you recommend a brand name? My tyres/rims are tubular.
10-03-11, 03:56 PM
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Go to the Topeak site among others for shock pumps. Or do an internet search for Bicycle Shock Pump.
I have a number of Topeak models, and would have no problem shipping to japan at a decent net cost, but I don't think that's the answer. Shock pumps have extremely small cylinders, usually about 1cm in diameter, so while they can develop high pressure vs handle force, they aren't suited for filling anything larger than a shock, and you'd be pumping forever trying to fill even a narrow tire.
Possibly the best bet is to use CO2 inflators. If you first bring the tire up to a high interim pressure with a pump, you can top it off very effectively with CO2. The only issue is that you'll need some trial and error to figure what starting pressure will yield the desired final pressure for a given cartridge size. Ideally you'l like to use 12g non threaded cartridges because these are far less expensive than the threaded type, and can be had at low prices in volume at sporting goods stores as paintball gun cartridges.
I have a number of Topeak models, and would have no problem shipping to japan at a decent net cost, but I don't think that's the answer. Shock pumps have extremely small cylinders, usually about 1cm in diameter, so while they can develop high pressure vs handle force, they aren't suited for filling anything larger than a shock, and you'd be pumping forever trying to fill even a narrow tire.
Possibly the best bet is to use CO2 inflators. If you first bring the tire up to a high interim pressure with a pump, you can top it off very effectively with CO2. The only issue is that you'll need some trial and error to figure what starting pressure will yield the desired final pressure for a given cartridge size. Ideally you'l like to use 12g non threaded cartridges because these are far less expensive than the threaded type, and can be had at low prices in volume at sporting goods stores as paintball gun cartridges.
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Just because I'm tired of arguing, doesn't mean you're right.
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WARNING, I'm from New York. Thin skinned people should maintain safe distance.
10-03-11, 03:56 PM
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While tire section and pressure are factors in rim dents or pinch flats, so are road conditions. But by far the biggest factor is rider habits. Some riders never get pinch flats or dented rims, and others always seem to even riding similar equipment on the same roads.
When a tire hits a 1" high bump at 20mph, the bike has roughly 1/50th of a second to lift over it, or at least high enough for the rim to clear. That involves serious G-force. The force difference between lifting the bike and rider sitting on the saddle, vs. just the bicycle with the rider using his legs as shock absorbers to let the bike alone rise below him is something close to 10:1.
When a tire hits a 1" high bump at 20mph, the bike has roughly 1/50th of a second to lift over it, or at least high enough for the rim to clear. That involves serious G-force. The force difference between lifting the bike and rider sitting on the saddle, vs. just the bicycle with the rider using his legs as shock absorbers to let the bike alone rise below him is something close to 10:1.
10-03-11, 04:05 PM
#37
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It bears repeating that weight alone isn't critical, but how you ride and use your legs and body as shock absorbers.
Years ago I had 2 riding buddies, a 105# ballerina, and a 260# linebacker (not really, just built like one). Guess who was death on her wheels. My 260# friend would pick a line around potholes, hop what he couldn't get around, or lift out of the saddle to let the bike float through rough sections. The ballerina rode like she was driving a car, you could hear the bike crash through everything, and as a result she was constantly denting rims.
Years ago I had 2 riding buddies, a 105# ballerina, and a 260# linebacker (not really, just built like one). Guess who was death on her wheels. My 260# friend would pick a line around potholes, hop what he couldn't get around, or lift out of the saddle to let the bike float through rough sections. The ballerina rode like she was driving a car, you could hear the bike crash through everything, and as a result she was constantly denting rims.
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An ounce of diagnosis is worth a pound of cure.
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WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FB
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An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
10-03-11, 05:33 PM
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I also ride at pressures much higher than most. I've found that if I ride at 140 + I have no issues with pinch flats. I weigh 200 Lbs riding 700x23 tires. If he is heavier than that, and or using a skinnier tire, he may need a higher pressure to avoid pinch flats as he alluded to. I also living in the midwest there aern't many switchbacks to be concerned with. Pinch flats however were a constant problem at 120 PSI.
Timtak- I have also found that a suspended seat post helps. I use a Thudbuster ST, it helps to minimize pinch flats too. Since using the Thudbuster and 140 PSI in my tires, I haven't had a pinch flat in MONTHS.
Timtak- I have also found that a suspended seat post helps. I use a Thudbuster ST, it helps to minimize pinch flats too. Since using the Thudbuster and 140 PSI in my tires, I haven't had a pinch flat in MONTHS.
And guess what? As you ride, every time you brake you wear away that rim a little bit.
10-03-11, 05:43 PM
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LOL. Perhaps I'll get that headcam.
I don't know what to say. The tyres are at about 150 psi now because it is really difficult to get them up any higher. When they were at 160psi it did not cause me any grief at all. What is the problem? My (almost unbranded) carbon frame seems to smooth out minor bumps pretty well and I ride on pretty smooth roads.
I have never been to a velodrome. I am a novice.
I weigh 160lbs but I don't think that the article that you were so kind as to share is divinely authored. Whatever the article says, I am speaking from my experience - I like the ride at 160 psi. I see no reason why the tyre and rim should explode.
bang.
The tyres (or at least one of them see addendum below), from a very reputable manufacturer, say that they are happy with 220 psi. I am under the impression that higher pressure in these tires reduce the probability of any type of flat. More than one reviewer has suggested that this is the case. There is also less rolling resistance. So all other things being equal - I was thinking of blowing them up to 170psi which is the middle of the range of one of the tires and within the range of the other.
All other things are not equal because the Lenz (thank you :-) and the SKS are alas over 120 USD where I am. The Lenz is even more expensive than the SKS. So....I have not made my purchase yet.
The rims did have a serial number on them when I took the tyres off. I googled the number and it was one of the OEM rims made in China. They look identical to those below, and were listed on the same site but they are lighter (if the guy that sold them to me can be believed).
https://ja.aliexpress.com/product-gs/...olesalers.html
If I new their numbers I'd recommend them because they make me very happy. I'll post a picture if I get time, showing the dollar store glue:-).
Addendum: The guy that sold them to me said that they were S3 tires. I got a flat in one and bought "another" S3 tyre but in fact that they were S33 on the bike at first, so I have a S33 on the back and an S3 on the front. The S33 have a 175psi limit.
Here we go, full disclosure (of my identity, though not the dollar store glue yet)
Tyres on bike
https://www.flickr.com/photos/nihonbu...n/photostream/
The photos from ebay
https://www.flickr.com/photos/nihonbunka/6207226996/
https://www.flickr.com/photos/nihonbunka/6206712279/
I was not keen on the strange floral design but now....It has grown on me.
Thank you for the seat post recommendation. I use an areobar and a very high seat post position. This means that I want to get as much forward offset as I can. Hence I use a USE Sumo seatpost with the saddle at the furthest forward extension it will go. I doubt that I would be able to find a suspended seat post with such a big forward offset. I will try to use my legs when going over bumps. Bang.
I don't know what to say. The tyres are at about 150 psi now because it is really difficult to get them up any higher. When they were at 160psi it did not cause me any grief at all. What is the problem? My (almost unbranded) carbon frame seems to smooth out minor bumps pretty well and I ride on pretty smooth roads.
I have never been to a velodrome. I am a novice.
I weigh 160lbs but I don't think that the article that you were so kind as to share is divinely authored. Whatever the article says, I am speaking from my experience - I like the ride at 160 psi. I see no reason why the tyre and rim should explode.
bang.
The tyres (or at least one of them see addendum below), from a very reputable manufacturer, say that they are happy with 220 psi. I am under the impression that higher pressure in these tires reduce the probability of any type of flat. More than one reviewer has suggested that this is the case. There is also less rolling resistance. So all other things being equal - I was thinking of blowing them up to 170psi which is the middle of the range of one of the tires and within the range of the other.
All other things are not equal because the Lenz (thank you :-) and the SKS are alas over 120 USD where I am. The Lenz is even more expensive than the SKS. So....I have not made my purchase yet.
The rims did have a serial number on them when I took the tyres off. I googled the number and it was one of the OEM rims made in China. They look identical to those below, and were listed on the same site but they are lighter (if the guy that sold them to me can be believed).
https://ja.aliexpress.com/product-gs/...olesalers.html
If I new their numbers I'd recommend them because they make me very happy. I'll post a picture if I get time, showing the dollar store glue:-).
Addendum: The guy that sold them to me said that they were S3 tires. I got a flat in one and bought "another" S3 tyre but in fact that they were S33 on the bike at first, so I have a S33 on the back and an S3 on the front. The S33 have a 175psi limit.
Here we go, full disclosure (of my identity, though not the dollar store glue yet)
Tyres on bike
https://www.flickr.com/photos/nihonbu...n/photostream/
The photos from ebay
https://www.flickr.com/photos/nihonbunka/6207226996/
https://www.flickr.com/photos/nihonbunka/6206712279/
I was not keen on the strange floral design but now....It has grown on me.
Thank you for the seat post recommendation. I use an areobar and a very high seat post position. This means that I want to get as much forward offset as I can. Hence I use a USE Sumo seatpost with the saddle at the furthest forward extension it will go. I doubt that I would be able to find a suspended seat post with such a big forward offset. I will try to use my legs when going over bumps. Bang.
A tire that is too soft will have more rolling resistance. This is true. A tire that is too hard will also have more rolling resistance, on any surface that is not perfectly smooth. The reason is that small bumps can be absorbed by the tire, rather than moving the entire bike, which takes far more energy than compressing the tire a bit.
https://velonews.competitor.com/2010/...ressure_145969
And here is Zipp directly:
Higher pressure is definitely slower on anything other than perfect surfaces. Think of it in terms of a bunch of 1mm tall bumps in the road. If you have a lower tire pressure, the casing of the tire will deflect over each bump (we'll assume the casing deflects the entire 1mm) converting a small amount of energy into heat as the casing deflects, but the amount of energy necessary to compress the air is almost non-existent. Now at a higher pressure, we will assume that the tire deflects half as much. Now the bike and rider are lifted by 0.5mm and the casing deflects by .5mm, the energy necessary to deflect the casing by .5mm is less than it takes to deflect it by 1mm, but is nothing compared to the amount of energy necessary to lift the bike and rider by 0.5mm, so the end result is that the total energy requirement for the high tire pressure condition is much greater.
The other thing that happens is that on smoother roads, high tire pressures keep the casing from deforming over and into small cracks and crevices and over pebbles, which means that some of the deflection is transferred into the tire tread, which is not as elastic as the casing. Excessive tire wear comes about as the tire rubber begins to fail in shear as it is deformed by the road surface, and this generates heat as well as breaks down the cross-linking within the tread material.... overall, you are using more energy to go slower and you're wearing your tires out faster. The problem is that high tire pressures feel fast as your body perceives all the high frequency vibrations from the road surface as being faster than a smooth ride.
The other thing that happens is that on smoother roads, high tire pressures keep the casing from deforming over and into small cracks and crevices and over pebbles, which means that some of the deflection is transferred into the tire tread, which is not as elastic as the casing. Excessive tire wear comes about as the tire rubber begins to fail in shear as it is deformed by the road surface, and this generates heat as well as breaks down the cross-linking within the tread material.... overall, you are using more energy to go slower and you're wearing your tires out faster. The problem is that high tire pressures feel fast as your body perceives all the high frequency vibrations from the road surface as being faster than a smooth ride.
Last edited by Nerull; 10-03-11 at 05:50 PM.
10-03-11, 06:00 PM
#41
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For a quarter you can go to a gas station and blow those tires right off the rims in a few seconds, with an adaptor.
10-03-11, 07:21 PM
#43
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Thank you. When I removed the keyword "absorber" I found that there are lots of shock pumps. In fact I am pretty sure that my local bike superstore stocks them on their Topeak rack. Amazon Japan also has the GIY41 which is designed to be used as mini tyre pump as well as a shock pump, and comes equipped with a presta adaptor, at about 36USD.
https://www.giyo.com.tw/web/03product/03shock/GS-41.htm
I'd be wary of "trial and error" with CO2 inflators.
I also realise that my "Bontrager TurboCharger" fills the tyres to 160psi and a bit more, a lot easier than my Topeak Joe Blow. I just assumed it would be as difficult due to it having the same maximum pressure guage reading, but the Bontrager TurboCharger has an all important narrower diameter, the significance of which I now know.
What with all the information from Zipp and others, I may stick with 160psi - which I can now reach. I generally only ride about 25km by the way so I don't mind a harsher ride.
The tyres are tubular. Rims, pressures, and dollar store glue:
https://www.flickr.com/photos/nihonbu...s/tufotyrerim/
https://www.giyo.com.tw/web/03product/03shock/GS-41.htm
I'd be wary of "trial and error" with CO2 inflators.
I also realise that my "Bontrager TurboCharger" fills the tyres to 160psi and a bit more, a lot easier than my Topeak Joe Blow. I just assumed it would be as difficult due to it having the same maximum pressure guage reading, but the Bontrager TurboCharger has an all important narrower diameter, the significance of which I now know.
What with all the information from Zipp and others, I may stick with 160psi - which I can now reach. I generally only ride about 25km by the way so I don't mind a harsher ride.
The tyres are tubular. Rims, pressures, and dollar store glue:
https://www.flickr.com/photos/nihonbu...s/tufotyrerim/
10-03-11, 09:46 PM
#44
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I found that there are lots of shock pumps. In fact I am pretty sure that my local bike superstore stocks them on their Topeak rack. Amazon Japan also has the GIY41 which is designed to be used as mini tyre pump as well as a shock pump, and comes equipped with a presta adaptor, at about 36USD.
https://www.giyo.com.tw/web/03product/03shock/GS-41.htm
https://www.giyo.com.tw/web/03product/03shock/GS-41.htm
The Giyo GS-41 is more of a mountain bike pump that eliminates the need for carrying 2 different types of pumps. The pump has 2 chambers and pistons in the body, the large outer piston for pumping tires which contains in it the shock chamber and piston for pumping up suspension. When using it as a 'high pressure low volume' shock pump the tire pump piston locks into place on the outer body, when using it as a 'low pressure high volume' tire pump the tire piston needs to be unlocked from the main body and the handle which attaches to the shock piston needs to click into place on top of the tire piston.
Only one piston/chamber should really be used at a time.
As a tire pump it's low volume because it's only a small pump, it works fine but it can take a while to pump a large volume tire. I think it would be a struggle to put 100psi into a tire with this pump, I've used one and it gets hard to pump around 80psi.
As a shock pump it works fine on shocks and suspension, I've used it to 200psi no problems. I'd never consider using the shock pump part of this pump to inflate a tire it'd take forever.
The fully extended GS-41:
10-03-11, 10:23 PM
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I may save up for the SKS Renncompressor then. I am not sure. If I don't get any flats at 160 psi I may stay at that.
10-03-11, 10:48 PM
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So you're aware, your odds of a pinch flat decrease at a higher pressure, but your odds of a debris caused flat tend to increase. As your contact patch shrinks, the pressure the tire exerts on the road increases, and any little bit of rock or glass is pressed into the tire harder than with a lower PSI or wider tire.
Over inflated tires also wear much faster than properly, or even under inflated tires.
Harsh rides scream increased rolling resistance by the way, it takes A LOT more energy to jiggle your body up an down vs the tire deforming and smoothing the ride out.
Over inflated tires also wear much faster than properly, or even under inflated tires.
Harsh rides scream increased rolling resistance by the way, it takes A LOT more energy to jiggle your body up an down vs the tire deforming and smoothing the ride out.
10-04-11, 01:14 AM
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I am aware that pinch flats decrease at higher pressures, but these are tubular tyres that do not pinch flats, and according to at least one review, I was under the impression that debris cause flats tend to decrease. There is some disagreement about this.
As for the rolling resistance, your comment coincides with the information from Zipp supplied above, but I have written to Tufo to ask them what pressure they recommend.
The Tufo website gives me the impression that higher pressures result in lower rolling resistance: "Our best selling road racing tyre. Very unique properties in this tyre weight category. High inflation pressure, minimal rolling resistance." (those last two phrases seem to be rolled into one) or elsewhere I read, "High max pressure for decreased rolling resistance." So there seems to be some disagreement about this too.
From my novice point of view, I wonder whether my Carbon frame, my saddle, or my bottom, may be absorbing the road irregularities, so there may be no need to jiggle my body up and down. If I added suspension in my seat post would that suddenly result in high pressure tyres having a low rolling resistance I wonder. Somehow it does not seem like a good idea to have suspension at the point of contact with the road since as well as absorbing road irregularities the area of tread and thus the friction with the road will also be affected.
I guess it depends in part on the tyre. Since the tyre I have in mind is rated to 220psi, I was under the (possibly/probably false) impression that 170 psi was not particularly high.
As for the rolling resistance, your comment coincides with the information from Zipp supplied above, but I have written to Tufo to ask them what pressure they recommend.
The Tufo website gives me the impression that higher pressures result in lower rolling resistance: "Our best selling road racing tyre. Very unique properties in this tyre weight category. High inflation pressure, minimal rolling resistance." (those last two phrases seem to be rolled into one) or elsewhere I read, "High max pressure for decreased rolling resistance." So there seems to be some disagreement about this too.
From my novice point of view, I wonder whether my Carbon frame, my saddle, or my bottom, may be absorbing the road irregularities, so there may be no need to jiggle my body up and down. If I added suspension in my seat post would that suddenly result in high pressure tyres having a low rolling resistance I wonder. Somehow it does not seem like a good idea to have suspension at the point of contact with the road since as well as absorbing road irregularities the area of tread and thus the friction with the road will also be affected.
I guess it depends in part on the tyre. Since the tyre I have in mind is rated to 220psi, I was under the (possibly/probably false) impression that 170 psi was not particularly high.
Last edited by timtak; 10-04-11 at 01:29 AM.
10-04-11, 10:35 AM
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With this:
It will only go to 185psi though......
Any higher than that and your should be looking at a screw type compressors.
There are hand pumps that will go that high but your going to be there awhile......They won't move much volume.
It will only go to 185psi though......
Any higher than that and your should be looking at a screw type compressors.
There are hand pumps that will go that high but your going to be there awhile......They won't move much volume.
10-04-11, 10:52 AM
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Like a person can lay on a bed of nails (skillfully) and not get impaled, if he stood on the nails with his feet, they'd likely impale him. A narrow tire at high psi cause objects to force themselves into the tire more easily due to the higher contact pressure between the tire and debris.
It's marketing man. Like siping on road tires, ridiculously high PSI ratings serve no purpose, and can actually reduce performance. If tires where marketed by things that mattered, manufacturers would be paying quite a bit to test each model for rolling resistance, puncture resistance, sidewall durability, wet traction, etc. So they just do what's easy, high TPI, high pressure, and let the marketing people fluff the rest.
Super narrow tires actually have higher rolling resistance, due to the deeper casing deformation (friction losses.) They do have lower wind resistance and weight, which is nice if you regularly ride at 20+mph or uphill all day.
It's marketing man. Like siping on road tires, ridiculously high PSI ratings serve no purpose, and can actually reduce performance. If tires where marketed by things that mattered, manufacturers would be paying quite a bit to test each model for rolling resistance, puncture resistance, sidewall durability, wet traction, etc. So they just do what's easy, high TPI, high pressure, and let the marketing people fluff the rest.
Super narrow tires actually have higher rolling resistance, due to the deeper casing deformation (friction losses.) They do have lower wind resistance and weight, which is nice if you regularly ride at 20+mph or uphill all day.
Last edited by MilitantPotato; 10-04-11 at 11:02 AM.