PRESTA valve size hole standard on quality rims?

[srands]

Why is PRESTA sized holes the standard on quality rims?

Why have 2 different valve types, when schrader car type valves are the obvious choice/standard?

I theory the following:

~ Cheaper MTBs: The majority have schrader valve rims, probably because they're wider rims (Less complicated design then their more expensive and better developed counterparts), because weight isn't an issue to the buyers of those MTB's (Well it won't be, cheap price matters to them). Obviously a schrader hole, can accomodate either a presta or schrader.

~ Quality MTBs: The majority have presta holes, because weight is an issue to buyers of these MTBs/RIMS, so the rims are narrower then on cheaper MTB's. Quality rims presumably have a presta size hole to retain greater rim strength, as there is more metal between the rim edge and the edge of the rim valve hole, so the chances of the valve rim hole cracking is less, then in comparison to a schrader size valve hole in a narrow MTB rim. And obviously a schrader valve will NOT fit through a presta size rim hole.

But the real question here is, "IF" quality mtb rims had schrader size rim valve holes, would these rims crack/snap because of the larger valve rim hole, or would the metal tolerate the reduced metal in that area from impacts?

Challenge: Go on name a few quality narrow MTB rims that actually have a schrader sized rim valve hole.

 

[Anthony]

I always assumed it was because (a) Presta is better and (b) you can make a hole bigger but you can't make it smaller. Well not so easily anyway - I know you used to be able to buy little adapters to convert a Schrader sized hole for use with Presta.

 

[marky2484]

If presta is besta, how come cars don't use 'em ??? :? :?

 

[srands]

PRESTA to SCHRADER valve adaptor PHOTO!

Er no, my thoughts are why not make schrader a standard on all bikes, since all cars use schrader, but I guess this comes down to MTB rim strength on really narrow rims, hence they (Rim/Innertube manufacturers) made up a narrower style valve (Presta).

Anyway here is a picture of a PRESTA to SCHRADER valve adaptor:

NOTE: To inflate innertube on a PRESTA innertube with a PRESTA to SCHRADER valve adaptor, the PRESTA open valve has to opened/released fully THEN screw on the PRESTA to SCHRADER valve adaptor THEN attach the pump, and PUMP IT UP!

Anyway it's not like innertubes (Schrader or Presta) lose air often, so mtb tyres don't need pumping up often.

It could be said that an advantage of PRESTA is that it is easier/quicker to LET OUT air! Because with a presta you simple undo the locknut, then press down the top of the valve to let out air, which in comparison to SCHRADER you have to find a small object (If your fingernail can reach!) to press the inside core of the valve downwards, to release/let down the innertube completely.

Here is the technical description of each valve:

Schrader Valve

Presta Valve

 

[technodup]

Re: PRESTA to SCHRADER valve adaptor PHOTO!

Er no, my thoughts are why not make schrader a standard on all bikes, since all cars use schrader

Going by that logic you'd want an engine next. All cars have them too.

I'd go the opposite way- always buy Presta tubes cos they go in any rim. And they look better, and I suspect are fractionally lighter.

 

[oldslalomskier]

I always assumed it was because (a) Presta is better and (b) you can make a hole bigger but you can't make it smaller. Well not so easily anyway - I know you used to be able to buy little adapters to convert a Schrader sized hole for use with Presta.

Those adpaters are still available. I use 'em all the time to convert all my rims to Presta, incl. MTB rims.

 

[oldslalomskier]

http://www.spacycles.co.uk/products.php ... 0s123p1765 but I use aluminum ones that drop in (WTB is the brand IIRC)

 

[WD Pro]

Challenge: Go on name a few quality narrow MTB rims that actually have a schrader sized rim valve hole.

Retro = 231's

WD

 

[WD Pro]

I always assumed it was because (a) Presta is better and (b) you can make a hole bigger but you can't make it smaller. Well not so easily anyway - I know you used to be able to buy little adapters to convert a Schrader sized hole for use with Presta.

Those adpaters are still available. I use 'em all the time to convert all my rims to Presta, incl. MTB rims.

WD

 

[feetabix]

ive known folk drill them out without problem.....