Road Cycling - presta-shrader adapter

Here is something that has been puzzling me. My road bike uses Presta tubes and I bought a couple of adapters so I can use a Shrader pump on them. Although I have screwed down the Presta knurled nut, I have left the adapter on the Presta valve. I realize that to pump air in, I'll need to unscrew that nut. However, my puzzle involves leaving the adapter on while I am riding. It seems to be a handy place for the adapters (i.e., better than hiding somewhere in my pack); but are there any drawbacks in doing so?

Nope.

Weight and it looks dumb.

As someone else has already mentioned... weight and it's rotating weight that will further off-balance your wheel. You also risk having it gradually back itself off due to vibration which will at the very least cause you to lose it (creating litter) and at worse have it hit you in the back or get lodged in your drivetrain thereby possibly ruining your whole day (not to mention the drivetrain).

Originally posted by khuon
As someone else has already mentioned... weight and it's rotating weight that will further off-balance your wheel. You also risk having it gradually back itself off due to vibration which will at the very least cause you to lose it (creating litter) and at worse have it hit you in the back or get lodged in your drivetrain thereby possibly ruining your whole day (not to mention the drivetrain). All applesauce.

Originally posted by pokey
All applesauce.

You've never had anything come loose due to vibration? Do you recommend the original poster loc-tite the adapter on? Admittedly the weight thing is grasping... one may or may not even notice it. It depends on the individual, the type of wheel, the weight of the adapter, etc...

However, I still maintain that there is a possibility that the adapter can work itself loose over time. If anyone wants to ride around with a presta-shraeder adapter attached to the valve then I recommend you double-check that it's tight before each ride. Then again, I also recommend you double-check tyre-pressure before each ride too regardless.

OK, Cadillac, listen to Pokey on this. He's the boyfriend with the straight 4-1-1. The added weight will be negligible. If you choose to ride with an extra few grams of rotating weight, it really shouldn't bother anyone else. I know plenty of people who ride with adapters on their valves. I've never heard of anyone losing one, much less causing serious bodily harm or drivetrain damage. If things threaded onto valve stems were liable to back off and fly away, no one could keep a valve cap on their car or bike tires.

You know, you don't even have to tighten that knurled nut down. The pressure of the air in the tube keeps the valve closed. Inside the adapter the little stem for that nut is protected. You certainly can screw the nut down, but you don't have to. It's kind of like wearing a belt and suspenders.

Just one caution. Don't fill your tires at the gas station. Those gas station compressors move a lot of air very fast and can blow your bike tire (especially if it's a skinny little road tire) right off the rim! ;)

So, put the adaptor on your valve stem, take off your clothes, and have a great ride, Caddy.

:love:

Originally posted by khuon
You've never had anything come loose due to vibration? Do you recommend the original poster loc-tite the adapter on? Adm It has an 'O' ring that does a good job of retaining it.Have you ever actually used one?

Originally posted by A.troll
OK, Cadillac, listen to Pokey on this. He's the boyfriend with the straight 4-1-1.

You know, you don't even have to tighten that knurled nut down. The pressure of the air in the tube keeps the valve closed. Inside the adapter the little stem for that nut is protected. You certainly can screw the nut down, but you don't have to.

:love: Troll,change your gender and be my GF. I was gonna mention not having to tighten the nut but figgered someone would take exception.Maybe they will anyway.

I have ridden many miles on my older road bike with the adapter in place and it has not budged. You are right that there is an O-ring in the adapter which prevents it from backing out. So losing it is no more an issue than losing the (chrome or plastic) retainer cap that fits over the Presta valve or the cap that fits over the shrader valve (which don't have an O-ring). I even rode 200 km in -12C temp and it did not come off.

The weight thing might be a small issue. I realize that rotating weight (i.e., heavier wheels) is harder to roll. E.g., 10 pounds on the wheels requires more energy to move than 10 pounds in a pack. Thus we have alloy wheels on bicycles, motorcycles, & cars.

The appearance factor is slight for me. At over 60, I am past impressing the ladies. When you're married to the best, you don't look at the rest.:)

Originally posted by pokey
It has an 'O' ring that does a good job of retaining it.Have you ever actually used one?

Havent used one in years but I just looked at mine and you're right so I sit corrected. I was just wary because I've had things like that knurled lockring come loose off my valve.

My suggestion is to go the other way. Get the larger push on adapter for your floor pump and change all of your frame pumps to go directly on the presta valve. This way you only have to back out the stop on the valve and not have to worry about carrying an adapter or loosing the adapter. Seems to make life so much easier. I agree with A Troll. Never pump at a gas station. Just my $.02

Originally posted by khuon
I've had things like that knurled lockring come loose off my valve. Save some hassle and rotational weight and toss the knurled nut.It serves no purpose.

When I have to use gas station air, I bend the hose in half in one hand to restrict & control the air flow, I keep the adaptor in my punture kit , some clever dick would lift it otherwise:mad: Most gas station tyre pumps dont seem to have a high enough top end pressure for road tyres but they are handy if you get a flat near one.;)

Originally posted by pokey
Troll,change your gender and be my GF.

Ah, heck, Pokey, change your gender and be my boyfriend! :p

Just teasing. You know Trollie loves you! :love: :love: :love:

I have one on my bike and never had a drama with it. Don't notice the extra gram or so it weighs and it's never looked like coming loose. Just check it once a week or so if you are still wary. Downside is that somebody might take a liking to it if you park your bike outside a shop for any length of time (but cyclists don't steal off other cyclists do they...).