Tyre/tube info and help please.
Tyre/tube info and help please.
Tyre and tube info required please!
Recently got a gravel bike and I’m stumped a bit.
It use 700 x 38c tyres. I’m after some inner tubes but fancy the slime ones. They only seem to do them in schrader valves and I’ve got presta. Is there another size I can buy like 27.5 x 1.5 for instance? After any info on what would fit nicely if possible.
Also, with co2 canisters, a 20g one will put 30psi into a MTB tube. If I use 2, I’m guessing it’ll only inflate the tube to the psi the canister is pressured to?
Thanks in advance.
Matt
Recently got a gravel bike and I’m stumped a bit.
It use 700 x 38c tyres. I’m after some inner tubes but fancy the slime ones. They only seem to do them in schrader valves and I’ve got presta. Is there another size I can buy like 27.5 x 1.5 for instance? After any info on what would fit nicely if possible.
Also, with co2 canisters, a 20g one will put 30psi into a MTB tube. If I use 2, I’m guessing it’ll only inflate the tube to the psi the canister is pressured to?
Thanks in advance.
Matt
From Leicester
Road and mtb are my thing. Aswell as cars,women,fire,meat and beer.
Road and mtb are my thing. Aswell as cars,women,fire,meat and beer.
Re: Tyre/tube info and help please.
No and no really.
You need the correct size tube really. They can be stetched but it's not great. Slime tubes are not brilliant anyway. They can work but if they don't they are a real mess and very hard to patch.
A normal CO2 catridge will inflate a gravel size tyre to enough.
You need the correct size tube really. They can be stetched but it's not great. Slime tubes are not brilliant anyway. They can work but if they don't they are a real mess and very hard to patch.
A normal CO2 catridge will inflate a gravel size tyre to enough.
Re: Tyre/tube info and help please.
Have you considered using a bottle of slime sealant for your existing inner tubes? If you remove the presta valve core you can pop some in?
Re: Tyre/tube info and help please.
Thanks for your reply, appreciated. Looks like I’ll stick to the proper size tubes then for piece of mind, maybe have a look at some better puncture protected tyres or some inserts for the tyres.mattsccm wrote: ↑27 Apr 2021, 5:46pm No and no really.
You need the correct size tube really. They can be stetched but it's not great. Slime tubes are not brilliant anyway. They can work but if they don't they are a real mess and very hard to patch.
A normal CO2 catridge will inflate a gravel size tyre to enough.
From Leicester
Road and mtb are my thing. Aswell as cars,women,fire,meat and beer.
Road and mtb are my thing. Aswell as cars,women,fire,meat and beer.
Re: Tyre/tube info and help please.
Hmmm, no I hadn’t actually. I’ll look into it thanks. Again, thanks for the reply.
From Leicester
Road and mtb are my thing. Aswell as cars,women,fire,meat and beer.
Road and mtb are my thing. Aswell as cars,women,fire,meat and beer.
Re: Tyre/tube info and help please.
Hi Matt,
I should add to my post that you’ll need to have inner tubes with removable valve cores. If you’re existing ones have them, then I’d suggest a bottle of sealant is the simplest way to go.
I should add to my post that you’ll need to have inner tubes with removable valve cores. If you’re existing ones have them, then I’d suggest a bottle of sealant is the simplest way to go.
Re: Tyre/tube info and help please.
Have you kevlar tyres if not I'd suggest investing in a pair as the Kevlar belt will be very hard for thorns or flints to penetrate.
Cheers James
Cheers James
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Re: Tyre/tube info and help please.
You can work out the pressure a CO2 canister will achieve fairly well. Calculate the volume of the tyre in cubic metres - for a 26 x 2 tyre, this is 0.559 x pi x (pi x 0.0254^2) = 0.00355 m3.
There are 16/44 = 0.36 moles of CO2 in the usual 16g canister. One mole is 0.024 m3 of gas at room temperature and pressure, so the gas in the canister expands to 0.36 x 0.024 = 0.00864 m3.
If all of this gas is forced into the tyre, the pressure will be 0.00864/0.00355 = 2.43 bar, or 36psi.
In practice you get less pressure than this because some of the gas is left in the canister at 36psi. You can correct for this by adding the volume of the canister, but it's negligible compared to the volume of the tyre.
I would recommend a 25g canister for MTB tyres or for touring tyres above 28mm width.
There are 16/44 = 0.36 moles of CO2 in the usual 16g canister. One mole is 0.024 m3 of gas at room temperature and pressure, so the gas in the canister expands to 0.36 x 0.024 = 0.00864 m3.
If all of this gas is forced into the tyre, the pressure will be 0.00864/0.00355 = 2.43 bar, or 36psi.
In practice you get less pressure than this because some of the gas is left in the canister at 36psi. You can correct for this by adding the volume of the canister, but it's negligible compared to the volume of the tyre.
I would recommend a 25g canister for MTB tyres or for touring tyres above 28mm width.
Re: Tyre/tube info and help please.
Thanks, I’m after 38mm with a presta.Eyebrox wrote: ↑27 Apr 2021, 9:21pm https://www.bikeparts.co.uk/products/sl ... e-tube-x-1
Also available in schrader valve format.
From Leicester
Road and mtb are my thing. Aswell as cars,women,fire,meat and beer.
Road and mtb are my thing. Aswell as cars,women,fire,meat and beer.
Re: Tyre/tube info and help please.
Just to update really.
I’ve found some Halfords alternative inner tubes that are self sealing with a presta valve that goes up to a 38mm tyre, so will give them a try at £5 a pop and see.
Also found some panaracer flat away Kevlar inserts for the tyres so have got 2 of those to try out as well.
Thanks all.
I’ve found some Halfords alternative inner tubes that are self sealing with a presta valve that goes up to a 38mm tyre, so will give them a try at £5 a pop and see.
Also found some panaracer flat away Kevlar inserts for the tyres so have got 2 of those to try out as well.
Thanks all.
From Leicester
Road and mtb are my thing. Aswell as cars,women,fire,meat and beer.
Road and mtb are my thing. Aswell as cars,women,fire,meat and beer.