Rim convertors (schrader to presta)

[Douglas Hall]

I've had one of these rubber rim valve hole convertors for a while, but just
got around to using it.

The rims on my mtb have different drillings, front to back - which is a
legacy of buying a groupset and wheelset for another frame, the wheelset was
identical to the wheelset on this mtb (Mavic 230 SBPs), but the internet
company that supplied the wheelset didn't supply the same valve drillings
for both wheels (even though I was very specific in my order). I didn't
bother at the time, and because the wheels were identical (bar the hubs
being STX compared with LX, and of course the front having a schrader valve
hole), for some reason I simply can't remember now, I seemed to swap front
wheels between the two bikes. Which, largely, was just dandy given they were
practically identical.

However, fate strikes - the other mtb that I put together, got nicked out of
a relatives garage - uncannily they didn't take the mtb I still have,
despite it being better, more expensive, better equipped and considerably
lighter than the one they took. I can only think it's perhaps because the
other one looked cooler. And this occurred during a period where I must have
had the front wheels on the other respective bikes (inexplicably, now,
because I can't for the life of me remember why I kept doing that...).

So I bought one of those rubber, grommet like valve hole convertors, and a
presta valved inner tube ('cos I just find it easier to deal with the same
valves in front and back). I've just got around to using them, and it's not
immediately apparent from which side of the rim I should insert the
convertor. If I put it in from the rim side, a bit of it sits just proud of
the rim surface, and vice-versa if I put it in from the inner-tube side of
the rim. Now the inner tube valve is practically all metal down to the inner
tube - so no rubber on the valve to get fouled by any expose metal edge of
the rim.

Could some kindly soul let me know which is the best way for the valve hole
convertor to be inserted? And if, ahem, the rubber grommit thingmy suffered
a slight tear, whilst being cack-handed trying to take it out of the rim
again ;-), is that likely to have compromised it at all? It's only a small
tear, it's not falling apart or anything.

Thanks in advance for any help.

 

[Martin Dann]

Douglas Hall wrote:
> I've had one of these rubber rim valve hole convertors for a while, but just
> got around to using it.
>
> The rims on my mtb have different drillings, front to back - which is a
> legacy of buying a groupset and wheelset for another frame, the wheelset was
> identical to the wheelset on this mtb (Mavic 230 SBPs), but the internet
> company that supplied the wheelset didn't supply the same valve drillings
> for both wheels (even though I was very specific in my order). I didn't
> bother at the time, and because the wheels were identical (bar the hubs
> being STX compared with LX, and of course the front having a schrader valve
> hole), for some reason I simply can't remember now, I seemed to swap front
> wheels between the two bikes. Which, largely, was just dandy given they were
> practically identical.
>
> However, fate strikes - the other mtb that I put together, got nicked out of
> a relatives garage - uncannily they didn't take the mtb I still have,
> despite it being better, more expensive, better equipped and considerably
> lighter than the one they took. I can only think it's perhaps because the
> other one looked cooler. And this occurred during a period where I must have
> had the front wheels on the other respective bikes (inexplicably, now,
> because I can't for the life of me remember why I kept doing that...).
>
> So I bought one of those rubber, grommet like valve hole convertors, and a
> presta valved inner tube ('cos I just find it easier to deal with the same
> valves in front and back). I've just got around to using them, and it's not
> immediately apparent from which side of the rim I should insert the
> convertor. If I put it in from the rim side, a bit of it sits just proud of
> the rim surface, and vice-versa if I put it in from the inner-tube side of
> the rim. Now the inner tube valve is practically all metal down to the inner
> tube - so no rubber on the valve to get fouled by any expose metal edge of
> the rim.
>
> Could some kindly soul let me know which is the best way for the valve hole
> convertor to be inserted? And if, ahem, the rubber grommit thingmy suffered
> a slight tear, whilst being cack-handed trying to take it out of the rim
> again ;-), is that likely to have compromised it at all? It's only a small
> tear, it's not falling apart or anything.
>
> Thanks in advance for any help.
>
>

 

[Martin Dann]

Douglas Hall wrote:

> Could some kindly soul let me know which is the best way for the valve hole
> convertor to be inserted? And if, ahem, the rubber grommit thingmy suffered
> a slight tear, whilst being cack-handed trying to take it out of the rim
> again ;-), is that likely to have compromised it at all? It's only a small
> tear, it's not falling apart or anything.

When I put mine in a couple of wheels last year, I pushed
the in from the inner tube side. The pressurised inner
tube then holds the grommet in place, and the grommet
stops the inner tube trying to push into the valve hole.

If inserted from the hub side, then the inner tube will
try and push the grommet out of the way, which would not help.

Also I don't think a small tear will matter.

 

[Douglas Hall]

"Martin Dann" <[email protected]> wrote in message
news:[email protected]...
> Douglas Hall wrote:
>
>> Could some kindly soul let me know which is the best way for the valve
>> hole convertor to be inserted? And if, ahem, the rubber grommit thingmy
>> suffered a slight tear, whilst being cack-handed trying to take it out of
>> the rim again ;-), is that likely to have compromised it at all? It's
>> only a small tear, it's not falling apart or anything.
>
> When I put mine in a couple of wheels last year, I pushed the in from the
> inner tube side. The pressurised inner tube then holds the grommet in
> place, and the grommet stops the inner tube trying to push into the valve
> hole.
>
> If inserted from the hub side, then the inner tube will try and push the
> grommet out of the way, which would not help.

Ah, I see now. Should have thought about that aspect of it, really.

Many thanks.

> Also I don't think a small tear will matter.

Thanks again.

 

[Pete Whelan]

I've always used a nylon washer under the rim tape, just large enough to
get the Presta valve through. Never been a problem in many years of use.

 

[Douglas Hall]

"Pete Whelan" <[email protected]> wrote in message
news:[email protected]...
> I've always used a nylon washer under the rim tape, just large enough to
> get the Presta valve through. Never been a problem in many years of use.

Thanks - good idea.