Inner Tubes

vickster

Legendary Member
I’d get 28-35. Presta or Shrader depends on what’s on the bike (probably Presta if not an MTB)
 

Cycleops

Legendary Member
Location
Accra, Ghana
Both are suitable but the 35-46 will be heavier but maybe more puncture proof. I'd go for the 28-36. Schrader valves will not fit the smaller holes meant for Prestas. 700c wheels are likely Presta.
 

vickster

Legendary Member
Definitely presta from the link in your other thread

What’s wrong with the tyres on the bike? Why not give them a go before putting m+ on (I’m not a fan of the horrid heavy, slippy, sluggish, hard to install things)
 

Nigelnightmare

Über Member
Replace like for like.
I.E. Get the same valve type as the existing tube on the bike.

*Edit* As others have said the rim will be drilled for a specific type of valve.
If it's drilled for presta then Schraeder wont fit through the valve hole.
If it's drilled for Schaeder then you'll need an adaptor to fit presta.

P.S. 28-35 would be better/easier & less likely to pinch when fitting the tyre.

HTH
 
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Presta valves will fill schrader holes, but not vice versa. Go for presta if possible, you can’t use a CO2 inflator with schrader. There’s a theoretical issue with the prestas being exposed a little bit from a schrader hole, but in reality it doesn’t matter, you can get grommets to fill any gap, but they’re not necessary in my experience.
 

andrew_s

Guru
Location
Gloucester
I'd get 35-46 tubes.
You probably won't get any fewer punctures overall, but a reasonable proportion of those you do get will be slow punctures that can be fixed at home rather than on the roadside.
 

fossyant

Ride It Like You Stole It!
Location
South Manchester
Planet X are doing tubes for 99p at the moment - fill your boots

https://www.planetx.co.uk/c/q/wheels/tyres-and-tubes
 

Ajax Bay

Veteran
Location
East Devon
You probably won't get any fewer punctures overall, but a reasonable proportion of those you do get will be slow punctures that can be fixed at home rather than on the roadside.
Why? As in why, if the OP chooses 35-45 inner tubes, will a greater proportion of the punctures the OP does get be 'slow' than if they used 28-35 tubes?

I'd add on the use of presta valves in rims drilled for schrader that it's worth cutting a little circle of discarded inner tube about 1cm in diameter, cutting a '+' sign in the middle (legs say 4mm) and pushing it over the valve before using the inner tube. Aim is to reduce the slim chance that the edge of the valve hole will cause damaging abrasion to the valve stem/tube junction. I do this for all my tubes as a matter of course (using them in rims drilled for Presta).
 
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andrew_s

Guru
Location
Gloucester
Why? As in why, if the OP chooses 35-45 inner tubes, will a greater proportion of the punctures the OP does get be 'slow' than if they used 28-35 tubes?
A 35-45 tube won't be stretched as much as a 28-35 tube when it's inflated inside the tyre.
Tubes are usually smaller than the smallest quoted size when they are inflated just enough to round them out (i.e. the mould size). A 35-45 tube will likely be about 30mm, a 28-35 tube would be about 23 mm. 30 to 35 mm is a lot less stretched than 23 to 35 mm, proportionally.

A thorn in an unstretched tube will often plug the hole it's just made, and small fragments of glass/flint that only protrude 0.25 mm inside the cover can often start a slow leak before it's fully penetrated the tube. In both cases a stretched tube will go flat within a few seconds.

I reckon 20% of my punctures are slow - found the morning after the ride, or slow enough to ride home on without pumping more than once or twice. My record was a thorn that stayed in for a couple of months before I got fed up with having to use the track pump on 3 times a week.
 
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