Tire question?
 

I just bought a used Tailwind. It has presta valves with schrader adapters. Do I check pressure and inflate the tire just like a do a regular schrader valve, or do I have to do something different? Also, I assume I need to get tubes with a presta valve rather than schrader. Correct?
The wheels are Alexrims DA16.

All suggestions highly appreciated. I am new to recumbents.
Bill

Not much difference in the way they work. Just remove the adapter, back off the knurled knob at the top of the presta valve, replace the adapter and use the pump the way you always have. After inflating the tire, remove the pump, remove the adapter, tighten the knurled knob again and replace the valve cap or adapter. Ride away.

If you really prefer schraeder valves on tubes, you can always carefully drill out the hole to accommodate the schraeder valve. It has negligible effect on the strength of the rim. If you stay with the presta valve, do what I do and buy a few tubes ahead of time so that you have them on hand when you need them.

When I back off the knurled knob on the presta, does air start coming out immediately ? And, when I finish inflating to desired pressure, and take off the adapter to turn the knurled knob back, do I lose pressure before turning it?
Thanks,
Bill

It's easier to set up your floor pump/frame pump for presta. Then you don't need those adapters. Even if you keep the adapters, you don't normally leave them on the wheel all the time.

With presta, the air pressure closes the valve (instead of a spring doing the job on a shrader valve) and you screw it in to secure it. Yes, when you screw it or unscrew it you can accidentally overcome the air pressure and manually open the valve. Just be careful to not do that. Pull gently on it as you screw/unscrew it. Having the adapter doubles your chances to let air out by mistake since you have to remove the adapter before you can screw the valve closed.

OK. So I do have to remove the adapter, then unscrew the valve, then put the adapter back on to put air in, right? The question is, when I unscrew the valve on the presta, does air start blowing out of the tube or not, and when I finish pumping air in, I assume that when I remove the hose and adapter, the presta will automatically close from the pressure inside the tube, then I just close the valve, and I am ready to ride, correct?

Is there supposedly some advantage to presta? I've never had anything with presta valves until this bike I got Friday.
Thanks,
Bill

Why presta valve tubes became popular
 

Once you fill the tube with air, the pressure inside the tire (tube) will hold the presta valve closed so that no air leaks out of the valve stem allowing you to tighten the knurled nut without losing pressure. You may lose a very little air when you remove the adapter if you bump the part that you are going to tighten.

Presta valves became popular in the US in the early 1970s when high pressure (100+ psi) clincher tires were introduced for "10 speed bike" owners. Presta valves were used in Europe way before that. The frame mounted pumps available in the 1970s did not work very well on a schraeder valve because you have to add in the pressure it takes to open the spring in the schraeder valve core. So, if you were attempting to get 110 pounds in a high pressure tire, the pump might have to deliver 130 - 140 psi to fill the tire to 110 lbs. Modern pumps are much better at delivering this high a pressure to the tire.

That said, I personally like presta valve tubes better. They are generally lighter than the ones you find in the mass merchandiser bike section. Why spend a lot of money to get a light trike only to add a couple of pounds with those wretched slime filled tubes that they sell at WalMart?

Thanks. What tube would you recommend for 20 x 1.75 Primo Comets with Alexrims DA16 wheels?
All my riding is on paved bike trails and streets.

If your Comets are labelled 1.75 they are probably getting up there in age. Several years ago Primo switched to calling what used to be 20x1.75 with the new name of 20x1.50". I've read that the 1.75 was actually about 1.5" wide - thus the switch to a more accurate name. Therefore, I would suggest a tube labelled for a range that includes 1.5" as the max. Important tip: You have to make sure not to buy tubes intended for 451 tires. 451 is the "other" 20 inch wheel/tire size and is different from 406-sized wheels/tires. I have no favorite tube brands.

I prefer schraeder valved tubes because the valve stem is tougher, less subject to damage by pump action. OTOH, presta valved tubes are easier to deflate and the stems comes in various lengths. My TE rims came drilled for schraeders.

You should be able to convert your pump head to presta. I find it useful to tap the valve head to unstick it before attaching the pump head.

MY lbs guy says most tubes are made by one manufacturer. In other words, pick one. Michelin does make a slightly thicker, butyl rubber tube they tout as better.at retaining air. IDK.

If you're using presta, you don't really *need* the adapters. You can convert most pumps to fit presta directly.

"Not much difference in the way they work. Just remove the adapter, back off the knurled knob at the top of the presta valve, replace the adapter and use the pump the way you always have. After inflating the tire, remove the pump, remove the adapter, tighten the knurled knob again and replace the valve cap or adapter. Ride away."

OK. I am officially an idiot. It tried this morning all methods listed above, both schrader with adapter, and presta without adapter. I could get no air to go in or come out, and I have no idea what my tire pressure is. These are 100 psi max tires, so maybe I am not pushing hard enough on the pump (dont' think so).

I guess I will have to go by a bike shop and get them to show me the ropes. **********????

This video might help http://www.youtube.com/watch?v=ncY1PEgSbI0

Highly recommend getting a pump with a head that will service both kinds of valves.

I have a pump that does both. Finally got things to work with he schraeder adapter after trying the presta with my pump and only succeeding in letting all the air out of my tire. I could not get the presta to take air. Looks like it's going to be trial and error for me. I just want to get it figured out before I'm 20 miles from nowhere and need air in a tube.
The video did help. It confirmed what I just did after I did it. I think the schreader adapter is going to be the way to go for me.
Thanks everyone.
Bill

Are you using a floor pump with two different holes on the head, one for each style? Or is it a frame (portable) pump? On some of those you have to take the head apart and reverse a part depending on what valve you are working with.

I have both.

After unscrewing the little knob on the valve, did you momentarily depress the knob to let out a bit of air? Presta valves tend to stick in the closed position and if you don't manually open them first and let out a little air the pump pressure is frequently not enough - even if you get it up way over 100 psi. But once you open it momentarily the pump pressure will suffice to do so again.

Set your pumphead for presta. No adapter is needed. Unscrew the knurled nut a couple of turns, and tap it to make sure it is not jamed shut. Put the pump on and pump to the desired pressure. Pull the pump off, screw the knurled nut tight and replace the cap.

Yes there is an aluminium adapter in the rim so that a schrader tube can be used in an emergency. Prestas work so much better tho--for example when putting tube back on rim the nut on the presta stem properly locate the stem, and prevents it from being pushed in when first inflating the tire.

I'm betting against that "idiot" thing. I HATE presta adapters. Here's why:

If that little stem on your presta valve gets bent, even a little, when you try to screw the presta adapter back on, it also screws that little nut back down. Now the valve won't open again.

How do you normally pump up your tires? If you have an air compressor at home, drill out your rims to accept schrader valve inner tubes. It's much faster and easier and my schrader chuck has a built-in air pressure gauge. If you use a floor pump, presta is easier so set up your pump for presta and pitch the adapters.

I had an issue finding Presta valved 20" 1 1/2" tubes for my new swb. I found that Scheel's (mega sporting goods store) had a number of Bontrager tubes in this configuration.

Normally I do make the effort to patronize lbs's, but I needed a tube and it was the weekend. Even during the week, normal hours, I'm going to have to hit up several stores to possibly come across a store locally selling high end 20" inner tubes. I was surprised to find them anywhere on a weekend, frankly. Pleased though.

The Alex DA16 rims probably have Schrader sized holes, with an adapter in them for the presta valve tubes. Go to the bike shop and ask them. If so, you can take out the adapter in the rim and get some tubes with Schrader valves to use. Get a 20 X 1.5-1.95 tube and set your frame pump up for Schrader. If you take out the adapters put some new velo tape on the rims.

I would replace eleven-year-old tires. Unless the rubber looks just like new. Are they blackwall, skinwall, gumwall? Any cracking or obvious deterioration?

They are blackwall, and the rubber does look like new. No cracks etc that I can see.

The 2000 TW that I bought in 2006 had skinwall Comets. Can't say for sure how they were made in 2001, but yours are likely newer than your bike.

It makes no sense to me to use presta tubes, then leave the adapter on the tube all the time. If you're more comfortable with shrader, get shrader tubes, don't leave that heavy bit of brass on your wheel all the time.

I think the biggest advantage to presta is that it doesn't require a big hole to be put in a narrow rim. Therefore,
IMHO presta works better for high pressure, skinny rims and tires, and shrader works better for low pressure, fat setups.

That's what I'm thinking. What is a skinwall?

From Wikepedia:
Skin wall
Tires with very little rubber, if any, covering the sidewall are called "skin wall". This reduces rolling resistance at the cost of less damage protection.