Wich valve for my tubeless?

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soulsurfer
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soulsurfer wrote:For any of these types of valves to fit and seal correctly, the base needs to mate to a flat surface, so alloy rims have a flat machined/cast in for this, ScootRS rims don't, they're curved, you'll be fitting a square peg into a round hole, although you may get it to seal, it's not ideal.
gadgetman wrote:That's nonsense Soulsurfer - there is a thick rubber seal fitted to all metal valves that takes up any profile differences between valve and rim. You obviously don't run one piece tubeless rims on your bikes
soulsurfer wrote:Look at 12 o'clock
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gadgetman wrote:Like I said - Nonsense you just don't like ScootRs rims which is fine but please try to base your negative comments on fact as just slagging a product off has no benefits to anyone. eg please explain how all the people with ScootRs tubeless rims with metal valves manage to go year after year without hardly any air loss if the valves don't seal , including the ones in the article written by Scootering's most respected journalist. Personal dislike of a product should remain just that - personal
Here's some more nonsense, nothing to do with what I think , or don't think, about ScootRS rims, just good engineering practice...
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Speed Demon
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gadgetman wrote:That's nonsense Soulsurfer - there is a thick rubber seal fitted to all metal valves that takes up any profile differences between valve and rim. You obviously don't run one piece tubeless rims on your bikes
To my knowledge all the bolt-in valves are intended to seat against a flat area, but as you say the thick rubber washers on the old-style ScootRS bolt-in valves take up any small curvature of the sealing surface with ease. The problem with the Bridgeport type valves is that the synthetic sealing washer is thin and less able to cope with bolting through a curved surface. I hoped it would be an easy solution but I wasn't really happy with the fit without some careful fettling of the hole.

BUT if you go back to the last issue of Scootering and look at Matthew's Series 1 you'll see that he successfully modified his ScootRS wheels to take Bridgeport valves. Probably the best solution would be to ask him exactly what he did. His user name on here is Matthew I believe...

I have found another possible though. These are fitted from the inside with a fixed end but it doesn't say what the sealing ring material is, or what size hole it is intended to fit.

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http://www.sip-scootershop.com/EN/Produ ... wable.aspx
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gadgetman
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Those look like the ones I've got on both my Lambretta and my Vespa supplied and fitted by MB Developments - all 6 fitted to Scootrs rims. And guess what, -none of them leak even after 4,000 miles and several years infact although i always check the pressures every week during the scooter main season ie April - November none of them ever need more than the odd top up more than once per year. A flat sealing surface is obviously a good thing but a slight curved surface is fine too. All this talk about 'round peg in a square hole' and 'you'll be lucky if you can get them to seal' is just total b****cks, sorry but that is a fact.
fairspares
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i fitted some of the bridgeport valves to a mates scootrs rims around 4 months ago and he,s had no problems with them , one thing though i had to take some material of the rim above the hole and around the back of the valve to get them to sit inside and not touching the rims . The sealing rubber is stepped and it took a few goes on one rim to get it to sit properly but in the end its all working fine with no leaks .
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corrado
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Speed Demon wrote:


I have found another possible though. These are fitted from the inside with a fixed end but it doesn't say what the sealing ring material is, or what size hole it is intended to fit.

Image
http://www.sip-scootershop.com/EN/Produ ... wable.aspx
I'm pretty certain that these are for the smaller hole so may not be suitable for later scootrs rims. It should be easier to fit tyres using these and easier to replace these valves with the tyre insitu because the valve protrudes less in the wheelwell.
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Speed Demon
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gadgetman wrote: All this talk about 'round peg in a square hole' and 'you'll be lucky if you can get them to seal' is just total b****cks, sorry but that is a fact.
No - what is a fact is that you don't know anything about fitting Bridgeport valves to your rims because you've never tried it, but you are willing to shout down people who have.

The ones in the photo I posted are not Bridgeport type - they were something I thought might work. I very much doubt that they are the same as fitted to your wheels because yours probably have a nut on the inside whereas these are sealed. yours are also probably 8mm hole valves and not 11.3. Unfortunately those who have had pull-in valves cannot convert to your exact type because their holes are already too large.

The images below show the problem which is that the Bridgeport valve (which was being discussed) has a very thin sealing washer and a large flat alloy surface. The "fact" is that the curvature of the rim means that the alloy touches down in two places before the gasket is evenly compressed. However both Matthew and Fairspares have got it to work.

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This isn't an anti-ScootRS thread, or anti-asian-products - it's just trying to answer the guys question about what valves to fit so please, chill the f@@k out.
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jason frost
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Just thinking out loud here, but could a dowty washer be used ?

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fairspares
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speed demon, your photos show exactly what i have done , saves me going out in the shed to take photos cheers.
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dansuper
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fairspares wrote:speed demon, your photos show exactly what i have done , saves me going out in the shed to take photos cheers.
But did you do anything else to get them to seal better where they don't sit flat on the rim?
fairspares
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no nothing .
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