Shrader to Presta Valve Adaptor

[Marchrider]

My front wheel is for Shrader (car tyre valve) and I use Presta's - I use a little collar as as an adaptor to fill up the void around the narrower valve

Yesterday I had a puncture and the aluminium adaptor had fused itself the the steel valve (galvanic corrosion) .
I fitted the spare tube with its presta valve and rode home without any bother - so to my question, are these adaptors necessary?


as for the stuck valve adaptor - couldn't even shift it in a vice and mole grips, its amazing how good galvanic corrosion is at welding stuff together (mended the puncture so it is back on the rim for todays ride)

 

[Vantage]

As long as you keep an eye on it, shouldn't be a problem. If the valves starts leaning in one direction, let the air out and reset the tyre till it's straight.
Heavy braking can cause the inner tube move independently of the tyre which can cause the valve to move and even tear off. Rare though I think.
I use presta valves with Schrader drilled rims and haven't had any issues so far.
I did at one time use plastic valve hole spacers. Made by Mavic if memory serves.

 

[Dogtrousers]

Can't answer whether they are necessary, but a quick google revealed you can get plastic ones for £3.26 for a pack of 10 from Amazon. So if you have any residual worry after reading @Vantage 's post it won't cost you much to resolve it in a non galvanic way.

https://www.amazon.co.uk/Schrader-Adapters-Manufacturing-Grommets-Convert/dp/B0DCK5DRTY/

 

[Marchrider]

just thought, I can just print some out - of course they can be made of plastic

 

[wafter]

Can't answer whether they are necessary, but a quick google revealed you can get plastic ones for £3.26 for a pack of 10 from Amazon. So if you have any residual worry after reading @Vantage 's post it won't cost you much to resolve it in a non galvanic way.

https://www.amazon.co.uk/Schrader-Adapters-Manufacturing-Grommets-Convert/dp/B0DCK5DRTY/

Yeah, while I'd not want to line Bezos' pockets further those appear to be the way forward.

 

[Dogtrousers]

Yeah, while I'd not want to line Bezos' pockets further those appear to be the way forward.

OK how about these. I'm not sure how evil these people are

£10.99 for a pack of 10
https://bankruptbikeparts.co.uk/pro...ader-presta-rim-8-5mm-to-6-5mm-10-pack-m40381

I used Google to do the searching so there's a bit of evilness in there I'm sure.

 

[Dogtrousers]

just thought, I can just print some out - of course they can be made of plastic

Or you could whittle your own from firewood like a good boy scout

 

[Marchrider]

Or you could whittle your own from firewood like a good boy scout

don't really have time at the moment, but it would be an interesting challenge, walls 1.25mm thick - probably Ramin would be best to use

 

[wafter]

OK how about these. I'm not sure how evil these people are

£10.99 for a pack of 10
https://bankruptbikeparts.co.uk/pro...ader-presta-rim-8-5mm-to-6-5mm-10-pack-m40381

I used Google to do the searching so there's a bit of evilness in there I'm sure.

Good work - granted, while quantifying exactly how evil they might be is tricky; I think we can all agree that they have to be considerably less evil than Bezos 👍

 

[Marchrider]

Printed one out - that should do the trick (still not sure if they are absolutely necessary)

 

[Dogtrousers]

Printed one out - that should do the trick (still not sure if they are absolutely necessary)
View attachment 757772

Necessary schmessessary it's a bit of blingy colour on your wheel.

 

[Marchrider]

Necessary schmessessary it's a bit of blingy colour on your wheel.

hi viz valve adaptor - health and safety, an Audi driver will spot that a mile off

(actually won't see any of it, will be all inside rim)

 

[Marchrider]

Or you could whittle your own from firewood like a good boy scout

Hardly whitling (whatever that be) but I decided to have a go - thought it would be an interesting little project, partially because a while ago I was ask to repair a childs wooden toy that had come apart and they had lost some of the bits, I 3d printed what was missing, but it looked awful, they were happy but it would have been so much better had I made them in wood, but I have no experiance of making very small components in wood - so this adaptor is a challenge

Found a bit of Elm in the fire wood store, Elm has a nice close grain that seems to dislike splitting so thought it might be OK, Ramin or hickory may have been a better choice

Cut a bit off, drilled and tapped it for M6

mounted in an M6 threaded bar and turned it down on the metal working lathe

wasn't gentle enough on my first go - it burst

but on the second go I only went down 0.2mm dia a pass - it worked - finished with 400 grit and then a dab of sanding sealer to give it a bit of colour

don't think it would last long on the bike - but interesting to make, even if I spent 2 hours!
took me 10 minutes to design and another 5 to 3d print the plastic one

 

[freiston]

That's very impressive work!

I bought a German import dynamo wheel that was drilled for Schrader for my utility bike but, like you, I use Presta valves. So I bought some adapters and forgot to fit one. That was last May (about 800 miles since) and I still haven't fitted one. I check the valve for straightness and damage when I pump it up but I've never had an issue.

 

[Marchrider]

I bought a German import dynamo wheel that was drilled for Schrader for my utility bike but, like you, I use Presta valves. So I bought some adapters and forgot to fit one. That was last May (about 800 miles since) and I still haven't fitted one. I check the valve for straightness and damage when I pump it up but I've never had an issue.

I can not imagine the tube suddenly deciding to squeeze its self through that little gap and go bang, it seems highly unlikely, I don't think they are needed - but I will probably continue to use one just in case!