cormacf

Just picked up my first 27" wheeled bike since the 70s. The rims are still in good shape, but they take Schrader valves, and I need new tubes. Any particular tube brand I should buy?

Classtime 

Most of the tubes these days come with threaded adapters so the presta valve will sit tight in the schrader hole.

Moe Zhoost

I'm partial to Schwalbe branded tubes and will buy them when I see a good price. Otherwise, I opt for Kenda or one of the cheap generic brands.

Ironfish653

Tubes are pretty stretchy. You can use a 700x28-32 in a 27x1-1/4

There’s only a little bit of difference in diameter between 700c and 27” (622mm vs 630). As long as the width is in the same range it’ll work fine. (1-1/4” is equivalent to 32mm)

my 27” bike runs presta valves for convenience (so I can share pumps/tubes with the 700c bikes)

DiabloScott

Presta valves in Schrader holes are usually not a problem.
Sure, get the right tubes if you're going to buy new, but if you have a presta tube lying around it should work fine for as long as you want.

tcs

Schwalbe:

Sactown_Albert 

You can purchase Presta valve tubes with a stepped nut that allow for their use on a Schrader drilled rim. The above pictures show them up close. Here are two shots with them in use. One with it unscrewed a little and one with it screwed all the way down.

Unscrewed to show Schrader hole.

Engaged so that Presta valve can be safely used.

RCMoeur 

Having looked at oodles of tubes, most current 27" Schrader tubes seem to be about the same quality (e.g. acceptable), as I suspect these days they all come out the same few Peoples' Revolutionary factories in China. Ditto with 700C tubes (the size difference being trivial to nonexistent in terms of inner tubes).

The co-op where I volunteer has been receiving Mitas brand tubes made in eastern Europe. These tubes in general seem to be working OK for now, but the rubber seems stiffer and less resilient than the Chinese tubes (not just the wall thickness, but the butyl rubber compound itself). Not sure how well they will hold up in the long term.

ThermionicScott 

+1 on Schwalbe tubes. I've been very impressed with their extra-lightweight tubes, and have no doubt that the regular models also inflate very evenly and hold air for a long time.

dddd

Don't use Presta-stem tubes!
The skinny stem either leaves a gap where smog-laded air might cause localized tube failure within as few as six months, and any threaded nut only tries to pull the metal stem free of it's fragile bonding to the actual tube.

Don't focus on brand or on the tube being for 27", any 700c tube can work without any fitment issue at all.

Focus instead on buying a tube that has a relatively wide (as measured folded flat) actual width, do not trust what is printed on the box or on the tube.
Tubes are "sized" all over the place relative to their rated sizing, so better to compare the width as presented right out of the box in the flattened state.

Don't use a tube narrower than 30mm (measured folded) in a 27x1-1/4" tire or it will have to stretch considerably to fill the volume of the tire casing.
With the tube so stretched, tiny thorn-type punctures will be pulled open to allow rapid loss of air, versus being able to ride home without stopping for a road-side repair.
So it's worthwhile to seek out the widest tubes that can be installed in your tires without issues such as having folds in the tube that might cause thumping when riding at high speed.
Wider tubes will tend to be heavier, but a tube rated for 32-38mm is often the best choice for use in these 27" wheel bikes I've found.
Not that I like waking up to a deflated tire, but it beats the alternative of having to fix one out on the road in blazing summer heat or with rain threatening.

Michelin even has patented Protek tubes made to achieve slower air loss by using a rippled wall that effects compression (versus tension) in the wall of the tube upon inflation. I bet that the ones listed here would fit into a 27x1-1/4" tire and give the absolute best air retention possible (short of using very heavy-walled tubes).
https://www.amazon.com/Michelin-Prot.../dp/B0064QIS9O

DiabloScott

I evaluate your claim to be hooey.
I ran Presta stems in Schrader holes on my commute bike for years in all kinds of weather without a flat. I had bought some new tires that were too wide for the Schrader valve tubes that came on the bike, so I put in some properly-sized Presta valve tubes that I had in my pile. There was simply no reason to swap them out once I had them in there.

dddd

Perhaps consider usage, as there can be a lot of vibration causing a presta stem to rock wildly in a Shraeder-sized hole, which causes the failures I described.

Also, most 27" rims will be single-walled, which narrows the possible span of support of the flexing valve (depending on a lot of variables).

I've many times used my spare Presta-valved tube to do a road-side fix, but my own experience has me swapping them out for solid Shraeder valve tubes at my earliest convenience.

And again, when tightening the nut on the added thickness of a double-walled rim, the nut is "bottoming" only on the bond between valve and tube itself, and which I have many times seen fail and leak.
This sort of failure is also not entirely uncommon to Presta-drilled rims, but where the rim seems to better support the nut's tension.
It's sometimes the case that those nuts need re-tightening as the rubber yields, which may eventually end in failure.
It's also the case as you noted that Presta valves can in many instances endure mis-fitment with no problems noted between tube replacements. Many of the tubes I use also come to me having previous usage, making them less robust than new tubes would be.
But even the thick, too-long (longer than needed) Shraeder valves installed on my truck's rims regularly failed from combined smog/aging/flexing.

Whatever valve is used and whichever type is carried as a spare, be sure to have an inflation device that is configured to handle what you have!

SurferRosa

Go presta, get a couple inexpensive rim grommets, and fuggetaboutit!

https://blueskycycling.com/products/...rims-to-presta

dddd

Genuine Mavic!

Good enough for me, as long as the style of rim (single or double-walled, thickness between walls) is compatible with the groove in the grommets.

I think that even just using rim tape "drilled" for presta valves might be of some value versus any likely-offset oversized hole that a Presta valve passes through.

ThermionicScott 

What I like about using tubes that are "big" for the tire, is that they can afford to be thinner, so the weight penalty need not be too bad.

I appreciate charts like this that let you compare models easily: https://www.schwalbe.com/files/schwa...le_Ansicht.pdf The AV17, rated up to a 47-622 or 40-635, but not too big for a 28-622 (and a reasonable 150g), looks like it would be a good choice for the OP.

dddd

I literally salvage and horde the very thin, Japanese-made tubes that I still find and take from 1980's road bikes, because they are so wide and unusually thin as compared to anything I can find at the shops. And of course no online seller discloses tube's folded widths.
These very old tubes turn up (some Specialized branded) at 29mm folded width but with a very low weight of 78g, which is unlike normal tubes today that are narrower and heavier.
A premium Turbo tube is only 67g or so, but is a narrow 22mm wide folded. They don't make a Turbo tube for wider road tires (20-25c is their printed rating).

I have used the old 29mm (actual folded width) Japanese tubes for my CX racing efforts over the past twenty-plus years in "38mm" Ritchey WCS tires that measured all of 34mm wide on my narrow Open Pro rims (I have since moved on to tubeless 42mm Rene Herse knobbies for all of my CX racing).

I find it odd that in this long-running age of progressively-wider road tires, that "standard" road tubes still haven't met the higher width/weight standards of the early 1980's.
Still waiting, even as tubeless threatens to take over (not going to happen until much slower-drying sealants get further developed).

DiabloScott

Your claim was that smoggy air would get in through the annular space around the stem and cause tube failure. That is hooey.

dddd

"I heard you the first time"

Makes me wonder what hooey means any more???

Smoggy air and stress at the rubber on the edge of the hole in the rim, unless good-fitting, Presta-sized holes in the rim tape (not a given, many times the "hole" part of the rim strip is gone, smog-rotted along the very thin web to either side of the hole, then perhaps glued down.

That's my experience, and I get that it's not been yours. Air quality here, funneled from Central Valley, is at high smog/ozone level, inner tubes left hanging in the garage or even packed in a porous saddlebag may not hold air after just a few months.

And the vibration that the Presta stem endures, cantilevered out from it's meager bonding to the tube.
Here's a photo showing the missing paint where a strudy Shraeder valve stem strikes the truck's rim with regularity.
Big difference in road speed, but big difference in tire cushioning, not to mention how much stiffer the Shraeder valve is than a Presta valve bonded to rubber sheet at it's base.



YMMV.

dddd

I can see how the step could help with stem support even without much in the way of tightening tension applied.

The neat thing is that these nuts work just as perfectly with all-Presta rims/tubes, even puts less in the way of scratches on the visible face of the rim if you were to forego using nuts later on. And I've seen lighter-weight alloy versions of these as well, maybe helps with the balance factor as tube stems have grown in weight as they've become longer.

It's always good to check the rim's valve hole for sharp edges, unless as I mentioned earlier a Presta-holed rim tape is really well-centered above the hole.

I've noticed over the years that thorn-proof Presta tubes tend to lose valve stems much more frequently, was an extremely common issue at the last shop where I worked. Gotta be more delicate with the pump head and hope that the stem gets at least some support at the rim with those.

albrt 

When I need to use a presta tube on a schrader rim, I find a little washer to go over the valve inside the rim. I figure it gives the rubber around the valve a little protection from the sharpish edges of the valve hole and prevents the rubber from stretching up into the valve hole until it bottoms out on the valve nut.

JohnDThompson 

Do you have a means of removing the smog from the air you pump into the tube?

dddd

You're joking, right?

Smoggy air in a tube or even a big container won't rot your tubes.

But a bike in a ventilated garage will see steady degradation from the steady input of photochemical smog molecules aka ozone.

Even in a decently-sealed house, the effect of outdoor smoggy air seems tremendously reduced, as contained air readily loses it's ozone concentration to whatever organic materials it is exposed to.

So, to answer your non-question, smoggy air pumped into the tube is going to present an insignificant amount of ozone exposure relative to how much ozone can attack any exposed area of the tube. But the exposed parts of a bike that's being ridden (or simply exposed to outdoor air) will be continuously subjected to ozone's full effects so may degrade rapidly if the air is bad.
It's perhaps worth noting that ozone degradation of rubber is proportional to the highly-variable ozone concentration of different regions and relative containments.

People living in lower-smog areas might never notice much aging of the sort caused by ozone, and tubes contained in a fitted tire with no big gaps leading to the tube can last 50 years even in an environment with some smog.
Tires on stored bikes coming adrift of the rim seating to expose the tube, valve-stem gaps at the rim, and well-aged "ventilated" sidewalls present the possibility for much more-rapid degradation of the tube.

ClydeClydeson

If using presta tubes in Schreader drilled rims, either get one of the stepped nuts shorn above, OR get a presta-schreader grommet to take up the excess space, OR find a washer that fits the outer diameter of the presta stem and put it between the tube and the rim and snug down the nut on the outside, OR put two nuts on the stem - one on the inside of the rim and one on the outside and snug them together.

I am happy to hear people have had good luck just using presta in a schreader hole without issue, but that has not been my experience - the tube sees a lot of extra stress trying to push itself through the hole and this often causes flats.

Chuck M 

Count me among those having no issues with presta tubes in Schrader rims. I use the nuts which fit into the Schrader hole to eliminate the tube or stem wearing against the rim. This smog induced source of deterioration seems far fetched and will not cause me to change my tubes back to Schrader and shouldn't deter someone from using presta tubes.

dddd

Likely also the case that the Presta valve in DiabloScott's wheel was fitted with rim tape having an accurately-sized and not over-stretched hole in it's rim tape, which I believe not only shields the tube from the "elements" but also acts as a stress-relieving buffer against the hole in the rim. There is just a huge amount of variability in all of the factors involved, literally every component (rim, rim tape and the tube's own reinforcement pad local to the rim), not to mention the air quality and the usage.
I believe that widely-differing results should expected, and that everyone's contribution has made this an interesting thread.