Similar idea to mine, I use Schwalbe 26x1.0-1.5 in my 2.2 tyres, never had a problem, they are 125g and I only pay £4 (about $6 US) each.

A friend uses 29er tubes in his home built 36er as the 36" tubes are 500g EACH.

So I'd say it's worth trying the 2.1's......

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Impoverished weight weenie wanna-be!
Budget 26" HT build viewtopic.php?f=10&t=110956

a) Why are you running tubes?

b) why are you running 2.4s and tweaking out about weight? If you're riding a bike like it should be ridden with 2.4s (ie, sideways, in the air) then lightweight stuff will just be a non-starter.

thankyou, i emailed sjs cycles yesterday and they told me........ "The SV14 X light tubes will be fine for use in your 2.4” tyres.
I wouldn’t recommend the 2.10” versions though, the thin rubber cannot cope with the extra volume needed to inflate a 2.4” tyre.
Normal weight 2.10” tubes tend to be fine, but not the extra light versions."

i think thats the crux is that there the extra light versions and best not to push them too much.but then it could just be them covering there asses perhaps

thanks

thanks for the reply 'Tokyo Drifter', if we go down this line of inquiry its going to end up in an argument.

Anything more helpful would be greatly appreciated thanks again

if your bedget will stretch to £ 9.99 consider:

Maxxis Fly Weight Innertube



At .45mm thin, flyweight inner tubes are the lightest butyl tubes known to mankind. Speed is increased because rotational weight is decreased. Flyweight tubes are packaged with a unique cloth rim strip to be used only with flyweight tubes.

•The lightest innertubes available
•0.45mm Thin
•For use with Maxxis rim strip (supplied)
•Valve Types: Presta valve, 48mm Presta or 60mm Presta
•Sizes: 26x1.50/1.75" , 26x1.95/2.125" or 700cx18/25c
•Weight: 86g (1.50/1.75"), 104g (1.95/2.125")
•Colour: Black

Tokyo Drifter makes a very valid point. 2.4 is massive, large even by DH standards.

Tubeless or regular tubes designed to work with the size tyres you use would certainly be far more logical than trying to get away an inadequate solution for a few g's. If the g's matter why so large tyres?

Lightweight tubes work perfectly fine if used as intended. Before tubeless I liked Conti Supersonics although I am not sure they are made beyond about 2.1...