potentially idiotic inner tube question
Discussion
I have that sick feeling i'm about to ask something stupid.. but here goes:
My road bike tyres have "700 x 25c" written on them. I'm looking for some spare inner tubes. The ones i've found on Wiggle which seem to be popular and have good reviews (http://www.wiggle.co.uk/vittoria-road-inner-tube/#buyitem) are marked as "700 x 19-23". So this falls a couple short of my "25c" tyres. Would this be an issue?
My road bike tyres have "700 x 25c" written on them. I'm looking for some spare inner tubes. The ones i've found on Wiggle which seem to be popular and have good reviews (http://www.wiggle.co.uk/vittoria-road-inner-tube/#buyitem) are marked as "700 x 19-23". So this falls a couple short of my "25c" tyres. Would this be an issue?
oh god and just to add to the confusion. i have now found two more inner tubes with the following descriptions:
700x18-25 Race 28
700x25-35 Cross 28
So is it better to go for the one where "25" is at the max range or where it is at the min range. And what's the difference between Race and Cross. And what in the name of holy krunk is the number 28 at the end supposed to mean?
Arrrrrgh
700x18-25 Race 28
700x25-35 Cross 28
So is it better to go for the one where "25" is at the max range or where it is at the min range. And what's the difference between Race and Cross. And what in the name of holy krunk is the number 28 at the end supposed to mean?
Arrrrrgh
You should be fine. They'll be a litte undersized but it shouldn't be a problem. I've run 1.9 inner tubes on my mtb without any problems if i've run out of the bigger sized ones. This was on 2.3 dh tyres too, so they get a hammering.
Eta race will be thinner/lighter so easier to puncture.
Eta race will be thinner/lighter so easier to puncture.
Both will fit, but the smaller tubes will be thinner.
If you want to go very light and no risk of punctures, then the thinner tubes will be fine.
If punctures is an issue, go for the right size. Don't go too fat though (28c), as you won't get them inside the tyre without pinching the tube.
The 28 is possibly the valve length. Check the depth of your rims, you might need a longer valve.
If you want to go very light and no risk of punctures, then the thinner tubes will be fine.
If punctures is an issue, go for the right size. Don't go too fat though (28c), as you won't get them inside the tyre without pinching the tube.
The 28 is possibly the valve length. Check the depth of your rims, you might need a longer valve.
rhinochopig said:
You should be fine. They'll be a litte undersized but it shouldn't be a problem. I've run 1.9 inner tubes on my mtb without any problems if i've run out of the bigger sized ones. This was on 2.3 dh tyres too, so they get a hammering.
Eta race will be thinner/lighter so easier to puncture.
sorry i should have mentioned i'm pretty 'simple' in these matters so a lot of that post (2.3dh, 1.9 inner tubes..) doesn't make sense to me..Eta race will be thinner/lighter so easier to puncture.
matt-ITR said:
Both will fit, but the smaller tubes will be thinner.
If you want to go very light and no risk of punctures, then the thinner tubes will be fine.
If punctures is an issue, go for the right size. Don't go too fat though (28c), as you won't get them inside the tyre without pinching the tube.
The 28 is possibly the valve length. Check the depth of your rims, you might need a longer valve.
So the "700x18-25 Race 28" is the one to go for which will fit and be better at preventing punctures?If you want to go very light and no risk of punctures, then the thinner tubes will be fine.
If punctures is an issue, go for the right size. Don't go too fat though (28c), as you won't get them inside the tyre without pinching the tube.
The 28 is possibly the valve length. Check the depth of your rims, you might need a longer valve.
I'm not sure what you mean by don't go too fat (28C) as I don't think i have a choice. The range quoted doesn't mean i can choose a specific size out of that range - rather that the tube in question will cover that entire range..
2seas said:
rhinochopig said:
You should be fine. They'll be a litte undersized but it shouldn't be a problem. I've run 1.9 inner tubes on my mtb without any problems if i've run out of the bigger sized ones. This was on 2.3 dh tyres too, so they get a hammering.
Eta race will be thinner/lighter so easier to puncture.
sorry i should have mentioned i'm pretty 'simple' in these matters so a lot of that post (2.3dh, 1.9 inner tubes..) doesn't make sense to me..Eta race will be thinner/lighter so easier to puncture.
2seas said:
matt-ITR said:
Both will fit, but the smaller tubes will be thinner.
If you want to go very light and no risk of punctures, then the thinner tubes will be fine.
If punctures is an issue, go for the right size. Don't go too fat though (28c), as you won't get them inside the tyre without pinching the tube.
The 28 is possibly the valve length. Check the depth of your rims, you might need a longer valve.
So the "700x18-25 Race 28" is the one to go for which will fit and be better at preventing punctures?If you want to go very light and no risk of punctures, then the thinner tubes will be fine.
If punctures is an issue, go for the right size. Don't go too fat though (28c), as you won't get them inside the tyre without pinching the tube.
The 28 is possibly the valve length. Check the depth of your rims, you might need a longer valve.
I'm not sure what you mean by don't go too fat (28C) as I don't think i have a choice. The range quoted doesn't mean i can choose a specific size out of that range - rather that the tube in question will cover that entire range..
The 28 figure indicates valve length. Unless you have aero / deep section rims, then these will fit.
rhinochopig said:
2seas said:
matt-ITR said:
Both will fit, but the smaller tubes will be thinner.
If you want to go very light and no risk of punctures, then the thinner tubes will be fine.
If punctures is an issue, go for the right size. Don't go too fat though (28c), as you won't get them inside the tyre without pinching the tube.
The 28 is possibly the valve length. Check the depth of your rims, you might need a longer valve.
So the "700x18-25 Race 28" is the one to go for which will fit and be better at preventing punctures?If you want to go very light and no risk of punctures, then the thinner tubes will be fine.
If punctures is an issue, go for the right size. Don't go too fat though (28c), as you won't get them inside the tyre without pinching the tube.
The 28 is possibly the valve length. Check the depth of your rims, you might need a longer valve.
I'm not sure what you mean by don't go too fat (28C) as I don't think i have a choice. The range quoted doesn't mean i can choose a specific size out of that range - rather that the tube in question will cover that entire range..
The 28 figure indicates valve length. Unless you have aero / deep section rims, then these will fit.
I can't believe how much money i've spunked away since getting into cycling!
rhinochopig said:
18-25c indicates that the tube will fit all tyres in that size range. Cross tubes will have better puncture protection than race but will be heavier.
The 28 figure indicates valve length. Unless you have aero / deep section rims, then these will fit.
Almost right, 28 in this case of Conti tubes refers to 700c. In Europe 28" = 700c and Conti are made in Germany.The 28 figure indicates valve length. Unless you have aero / deep section rims, then these will fit.
http://www.conti-online.com/generator/www/de/en/co...
The valve lengths vary on these Race 28 tubes: 36mm, 42mm, 60mm and 80mm are available, although the latter only in presta form. The smaller valve lengths are available in both presta and schrader
http://www.wiggle.co.uk/continental-quality-road-i...
As far as I know, it goes:
Race 28 = normal weight butyl rubber. 100g each
Race 28 Light = thinner butyl rubber. 65g each
Race 28 Supersonic = latex. 45g each
Latex obviously loses air much faster that butyl, and is less puncture resistant. Depends how often you want to pump your tyres up
itsnotarace said:
As far as I know, it goes:
Race 28 = normal weight butyl rubber. 100g each
Race 28 Light = thinner butyl rubber. 65g each
Race 28 Supersonic = latex. 45g each
Latex obviously loses air much faster that butyl, and is less puncture resistant. Depends how often you want to pump your tyres up
Not quote right. Continental don't make a latex tube, the supersonic is just a super lightweight butyl tube. Latex tubes do exist though, Michelin among others make them.Race 28 = normal weight butyl rubber. 100g each
Race 28 Light = thinner butyl rubber. 65g each
Race 28 Supersonic = latex. 45g each
Latex obviously loses air much faster that butyl, and is less puncture resistant. Depends how often you want to pump your tyres up
Latex tubes do loose air faster, somewhere in the region of a few psi per day.
But they are more puncture resistant than butyl tubes, which is why they are popular.
I think latex tubes are great for road racing. They feel better and are lighter, but stick to butyl for training.
While we're on about silly questions; why have light weight tubes?
The difference can't be that great, apart from the weight/puncture risk ratio and the more weight around the rim of the wheel the better the wheels work as flywheels. The centrifical momentum of the extra weight as the wheel rotates assists forward movement doesn't it?
I seem to remember a chap who used to part fill his tyres with water. At slower speeds gravity held the water in place but as his speed increased the water would be held on the inner wall of the tyre. When he braked the momentum allowed the water to flow around the wheel.
The difference can't be that great, apart from the weight/puncture risk ratio and the more weight around the rim of the wheel the better the wheels work as flywheels. The centrifical momentum of the extra weight as the wheel rotates assists forward movement doesn't it?
I seem to remember a chap who used to part fill his tyres with water. At slower speeds gravity held the water in place but as his speed increased the water would be held on the inner wall of the tyre. When he braked the momentum allowed the water to flow around the wheel.
Edited by Liquid Knight on Wednesday 18th January 09:44
rhinochopig said:
18-25c indicates that the tube will fit all tyres in that size range.
I fitted some new tyres to my hybrid (700C) before Christmas and wondered about this - I still don't know the answer. My old tyres were 700x45C and the new ones 700x40C, but the old inner tubes were marked 700x45C (not a range of sizes). I thought it wouldn't make any difference so bunged the existing tubes in, but amazingly one of them made a break for freedom at 60psi, pushing the new tyre off the rim. Fortunately just when the bike was sitting in my garage.This was probably entirely due to me not seating the tyre properly but I went out and bought some Conti inner tubes which had a range covering 700x40C anyway. Was that really necessary?
Liquid Knight said:
While we're on about silly questions; why have light weight tubes?
The difference can't be that great, apart from the weight/puncture risk ratio and the more weight around the rim of the wheel the better the wheels work as flywheels. The centrifical momentum of the extra weight as the wheel rotates assists forward movement doesn't it?
I seem to remember a chap who used to part fill his tyres with water. At slower speeds gravity held the water in place but as his speed increased the water would be held on the inner wall of the tyre. When he braked the momentum allowed the water to flow around the wheel.
Yes and No. You're seldom steady state on a bike. Rotational mass is an issue with braking, acceleration, and steering though. Plus lighter tubes and tyres reduce the mass of the bike, which makes climbing easier. The difference can't be that great, apart from the weight/puncture risk ratio and the more weight around the rim of the wheel the better the wheels work as flywheels. The centrifical momentum of the extra weight as the wheel rotates assists forward movement doesn't it?
I seem to remember a chap who used to part fill his tyres with water. At slower speeds gravity held the water in place but as his speed increased the water would be held on the inner wall of the tyre. When he braked the momentum allowed the water to flow around the wheel.
Edited by Liquid Knight on Wednesday 18th January 09:44
It's more so important on MTB for damping reasons. The higher the mass the damper has to cope with the slower it will react, so grip is reduced as the wheels will be in contact with the ground less. A practical example is to see how fast you can shake your fist. Now add a kilo weight into your hand and see how fast you can shake it. Not only will you work harder, you'll be slower. In a damper, that extra work manifests as heat which effects the damper efficacy. Hot air increases pressure in the damper.
Rotational mass and unsprung mass should always be as low as practically possible, be it on cars or bikes.
Jobbo, I've never had a problem running tubes just either side of the recommendation. It sounds more like you've pinched the tube with the tyre bead and the tube has lifted the bead off the rim.
rhinochopig said:
Jobbo, I've never had a problem running tubes just either side of the recommendation. It sounds more like you've pinched the tube with the tyre bead and the tube has lifted the bead off the rim.
I think you're right (despite being really anal about not pinching the tube usually), though if that's the case it was probably a good thing I bought new tubes anyway.Gassing Station | Pedal Powered | Top of Page | What's New | My Stuff