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lordofthemark
12-13-2016, 12:10 PM
Thanks to KWarkentian for lending me a bike.

Upon further examination of the bike, it reveals a question for the forum. The wheelset is Mach 1 CFX, and the tubes KW had in them were Prestas. I continue to want to want to use my bikeroom motorized air pump for quick inflation, and it is schrader only (the bike room has, or at least had, presta-schrader adapters, but I find using them awkward) I would like to switch out the presta tubes for schrader tubes, but without taking the tubes out its hard for me to see the valve hole on the wheelset to see if there is actually room to do that. I have found wheelset specs online, but nothing about valve hole size. Is there some other way to figure this out easily without taking the tube out?

If not should I

1. Go ahead and take the tube out, because that is such a basic easy thing to do

2. Just man up and use the adapters, because presta good, schrader bad.

Assuming I find out that the holes are sized for presta and not schrader, I will have to do number 2 anyway. Even if KW gave permission (chance to chime in here!) I don't think I would want to drill the wheels.

TwoWheelsDC
12-13-2016, 12:41 PM
What do you mean it's hard to see the valve hole? If the hole is Schrader-sized, but the tube has a presta valve, it should be pretty obvious. Do you mean it's hard to see because of the nut on the valve stem? That nut has essentially no use whatsoever (except when you're installing an empty tube), so you can just remove it and see if there's a big gap between the valve stem and the edges of the valve hole. No gap = presta only.

lordofthemark
12-13-2016, 12:43 PM
What do you mean it's hard to see the valve hole? If the hole is Schrader-sized, but the tube has a presta valve, it should be pretty obvious. Do you mean it's hard to see because of the nut on the valve stem? That nut has essentially no use whatsoever (except when you're installing an empty tube), so you can just remove it and see if there's a big gap between the valve stem and the edges of the valve hole. No gap = presta only.

yes. I haven't touched the valve stem nut.

TwoWheelsDC
12-13-2016, 12:59 PM
yes. I haven't touched the valve stem nut.

Just take that off and you should be able to tell pretty easily...no tube removal required. Like I said, the nut does nothing once the tube is inflated...it's only purpose is to hold the valve stem in place when you're attaching a pump to an empty tube.

lordofthemark
12-18-2016, 08:12 PM
Finally went down to the bike room and checked it out. Those are definitely small prest sized hold on the wheels.

I'm thinking the reason I have trouble with the adapters is that they are not standard adapters. Does this look like a presta schrader adapter?



12962

I think I need to go pick up some simple adapters.

hozn
12-18-2016, 09:27 PM
I'm thinking the reason I have trouble with the adapters is that they are not standard adapters. Does this look like a presta schrader adapter?

No, that looks like something you'd use to inflate a kiddie pool with a (shraeder) floor pump.

Any bike shop should have a presta-shraeder adapter. Which I guess is useful if you want to use free trail-side air.

dbb
12-18-2016, 09:59 PM
This

http://www.chainreactioncycles.com/us/en/stans-no-tubes-presta-schrader-valve-adapter/rp-prod38828?gs=1&gclid=Cj0KEQiAhNnCBRCqkP6bvOjz_IwBEiQAMn_TMdTQjXzC 46kcBGMzLZpq0rLXXoEXvmofBlUwkxkkxAUaAvlv8P8HAQ&gclsrc=aw.ds

lordofthemark
12-19-2016, 09:19 AM
No, that looks like something you'd use to inflate a kiddie pool with a (shraeder) floor pump.

Any bike shop should have a presta-shraeder adapter. Which I guess is useful if you want to use free trail-side air.


Or the pump in my building bike room.

hozn
12-19-2016, 09:31 AM
Or the pump in my building bike room.
Really, a schraeder-only pump head?!? Someone should tell them that bicycles use presta valves. I don't think you could even buy a pump from a bike store that wasn't dual head (or presta-only). Maybe you could find a schraeder-only pump at Target, though.

lordofthemark
12-19-2016, 10:17 AM
Really, a schraeder-only pump head?!? Someone should tell them that bicycles use presta valves. I don't think you could even buy a pump from a bike store that wasn't dual head (or presta-only). Maybe you could find a schraeder-only pump at Target, though.

It's an auto style compressor, not a floor pump. I don't know where they got it, or how they decided to install it. They only asked me about bike room needs a couple of times at most, and I think my main focus was on it being fob accessible (the old bike room was and is opened by keys kept only at the front desk, so not accessible at hours when the concierge is not in). I didn't expect the tools and the pump the put in. And I am not about to complain about it.

drevil
12-19-2016, 11:27 AM
It's an auto style compressor, not a floor pump. I don't know where they got it, or how they decided to install it. They only asked me about bike room needs a couple of times at most, and I think my main focus was on it being fob accessible (the old bike room was and is opened by keys kept only at the front desk, so not accessible at hours when the concierge is not in). I didn't expect the tools and the pump the put in. And I am not about to complain about it.

If you want to be nice guy, you can spend <$10 to buy this press-on presta valve adapter, which you can zip tie close to the end of the hose. When you want to use it, you can just press on the adapter onto your Presta valve tube, then use the Schraeder valve compressor pump. It's nice and quick because you don't have to screw it onto either, and it's always handy because it'll be zip tied onto the pump.

12969

It's available from QBP, so any shop can order it, or you can get it directly here: http://www.aebike.com/SKS-Pump-Adaptor-with-Chain-Schrader-to-Presta_p_21402.html

lordofthemark
12-28-2016, 10:33 AM
Just to wrap this up, I bought a pair of the ordinary cheap adapters, and they work fine.