tube size confusion

[s.e.charles]

i have Panaracer Pasela tyres ('83 Raleigh mixte) marked 27 x 1.25" ----- 32 - 630

i want tubes with a minimum 40 mm presta valve stem. (adapters in the rims)

sizes i see at suppliers dance around these numbers, but not much hits the mark.

Q: what latitude do i have?

thanks

 

[Midlife]

Something like this ?

https://www.bikeparts.co.uk/products/schwalbe-sv17-700c-28-47c-27x1-1-4-40mm

 

[s.e.charles]

kind of sort of; by my word the range of sizes completely baffles me.

 

[non-fixie]

The SV17 will work, although I prefer the slightly narrower SV16, as it is a bit lighter and will stretch to 32mm as well. And anything labeled "622" will work just as well on 630 rims.

 

[s.e.charles]

if this tube is 27.5, how does it get rated 630?

the box indicates 28" - and is only adding to my confusion.

i am assuming it does Not have the weight of the "marathon" line of puncture resistant tubes - which are heavier than i need.

thanks

ps: i just ordered (2 + spare) the SV16 tubes w/ 40 presta from the Big A; so i can send them back if it's a problem.