Help with Bontrager tubes needed

Cerulean said:

I'm getting back into bicycling after many years. The tubes I was given when I purchased the bike were Bontrager 27 X 7/8 - 1 tubes with the 48MM valves. I am not used to these valves at all. My old Trek didn't use these tubes.

My problem is I've gone through 3 tubes, not due to being flat. The valve and valve stems are too too fragile. The first one the little spigot at the top bent and broke off in my pump. The next on the valve itself broke in half while pumping, and the last one the spigot broke off while pumping.

😕 Is it my pumping technique (too hard)? Is it my pump (using a Blackburn mini)? Is it the brand? Or is it just faulty tubes and my bad luck? Are there alternative brands that use a different valve system? After all, I had to throw away two new tubes because of this. This is getting expensive when living on a budget. I'm frustrated. Now I have to walk 2 1/2 hours to for an appointment today. I don't mind walking but I thought I'd shave off a bit of time.

It's your technique ...

I know someone else who (to my surprise) probably did the same thing you did (he had the same results) ...

You want to stabilize the stem & pump by hooking your fingers around one of the spokes AND your thumb around the valve-and-pump-head ... that is, you don't want to rock the stem when you are inflating the tire!

MINI-pumps are a bad idea ... barely suitable as a last resort ... they take at least 2x as long to inflate the tire than with a "full length" frame pump ... mini-pumps are "okay" for MTB tires because the PSI is much lower (but, the volume to fill the tire is greater) AND because they can be carried inside the rider's pack (if s/he is carrying one) rather being bounced off the frame.

The maximum PSI for most mini-pumps is in the 65PSI range -- you want a pump that can handle 100PSI, or more.

Also, you want a floor pump to use when you are home (i.e., any time that you are NOT on the road) ...

If I weren't as frugal as I am then I would buy an air compressor and install a SILCA pump head on one of the hoses to use when I am not on the road.

Cerulean said:

I'm getting back into bicycling after many years. The tubes I was given when I purchased the bike were Bontrager 27 X 7/8 - 1 tubes with the 48MM valves. I am not used to these valves at all. My old Trek didn't use these tubes.

My problem is I've gone through 3 tubes, not due to being flat. The valve and valve stems are too too fragile. The first one the little spigot at the top bent and broke off in my pump. The next on the valve itself broke in half while pumping, and the last one the spigot broke off while pumping.

😕 Is it my pumping technique (too hard)? Is it my pump (using a Blackburn mini)? Is it the brand? Or is it just faulty tubes and my bad luck? Are there alternative brands that use a different valve system? After all, I had to throw away two new tubes because of this. This is getting expensive when living on a budget. I'm frustrated. Now I have to walk 2 1/2 hours to for an appointment today. I don't mind walking but I thought I'd shave off a bit of time.

alfeng's advice is all good of course, but I say it's the tubes because I've had the same problem with Bontrager "long stem" tubes, and only Bontrager. Have never had that failure with Michelin, Conti or even other "no-name" tubes. Thought the failures could be caused by a rough valve-stem hole, but I found the bonding area for the stem at the base of the tube is just weak, causing the tube to fail there prematurely. After 3-4 failures like this on tubes installed for just a few months, I stopped buy them from my LBS...despite the 3/$10 pricing.

Compare the valve-base reinforcement on a Michelin or Conti tube to the Bontrager and I believe you'll see the difference immediately.

Just a thought. Are you installing Presta tubes in a wheel whose valve hole is the larger-diameter Schrader size? If so, at your LBS you can get an adapter (essentially a bushing with a lip on it) to adapt the wheel for use with Presta tubes for a better fit and reduced probability of damaging the valve.

The other random thought is whether the little brass locking ring (that snugs the valve stem to the rim) is in place, as this provides some support of the valve stem while you are applying and removing the pump head. Especially if you are using a frame pump where the pump head is part of the pump itself (and not at the end of a long flexible hose), you can put some stresses on the tube/stem interface, while pumping.

I'm undecided on use of the stem nut. I know they come with each tube, and the instructions (Conti at least) say to use the nut, so it's probably a good practice. But I went for years without using them, and never had a problem. Also the Michelin tubes I've used have a smooth (unthreaded) stem so of course no nut can be used on them, and I never experienced a failure at the valve stem interface. Went back to the stem nut when I started having the Bontrager tube failures, but it didn't seem to help at all.

I also bin the washers. Some I do keep as potential fixes for something else. I've never done damage to a tire because the washer wasn't there. Michelin tubes, with smooth stems, show that you don't need the washers, and as it happens, they're damned fine tubes.

I use bontrager XL tubes all the time. I use 36mm and use extenders for deep wheels.

Get a track pump (best thing since sliced bread) and always exercise care when disconnecting pump from valve. Reef the thing off and you'll rip the valve from the tube every time. I have silca style pump valve and need to wriggle the pump valve down off the tube valve. Small price to pay for properly pumped tyres every time.

Mini pumps are for use as a portable if you puncture on the road.

dhk2 said:

I'm undecided on use of the stem nut. .

If you have a presta valve and a presta valve hole, they are useless and only add weight and slow down your tire change. If you have a schraeder drilled rim and are using presta valves or are using really long valve stems in a rim that doesn't need them. The washers can help keep the valve from moving back and forth and damaging the tube at the base of the stem.

tafi said:

I use bontrager XL tubes all the time. I use 36mm and use extenders for deep wheels.

Get a track pump (best thing since sliced bread) and always exercise care when disconnecting pump from valve. Reef the thing off and you'll rip the valve from the tube every time. I have silca style pump valve and need to wriggle the pump valve down off the tube valve. Small price to pay for properly pumped tyres every time.

Mini pumps are for use as a portable if you puncture on the road.

Haven't ever used the 36mm XL tubes. I had problems with the Bontrager 48mm standard tubes; believe that was the same tube the OP had the failures with. Since I've never had a problem with valve stems in the past, and have been using the same wheels and pump for the past 6 years, after the third failure at the valve stem base it became obvious that something was wrong with the tubes. As I mentioned above, the Conti 42mm tube has a much thicker rubber bond between stem and tube.

Didn't mean to say that all Bontrager tubes are junk, just the ones I bought in 08 and early 09. It could be that my LBS (Trek dealer) got a defective lot of (48mm) tubes in 2008, and that Trek has changed suppliers by now. The tubes were priced right, at 3/$10, but not a bargain if they fail after a couple of months/1000 miles due to the weak valve stem base.

I think it's the Bontrager tubes. I've had 3 or 4 valve-stem failures in the past year, both at the base of the stem and in the internal valve mechanism. That's out of about 6 tubes total (I patch leaks when I can rather than replace tubes).

In my case they are Bontrager 700x18c-23c road-bike tubes with the long 48mm stems. Bontrager is what my local bike shop stocks; I think I used other brands before moving to this area, and I don't recall these kinds of problems back then. I guess I'll have to take my local business to the Internet (sigh).

Failures at the base of the stem occurred after fixing flats on the road using a hand pump. It's basically impossible to inflate high-pressure tires with a hand pump without putting some stress on the valve stem - and the manufacturer should know that. But I'm very careful -- I hold the base of the pump (attached to the valve) against a fence-post or similar while pumping, so the force is resisted by the post and the wheel and valve just sit there more-or-less loose. But there is always going to be a little wiggling while the pumping is going on, and tubes should be engineered with that in mind.

Today the internal valve mechanism would not shut off after I topped up using a new floor pump, on a tube which has never been repaired (just inflated with a floor pump). With a floor pump, the attachment head is on a flexible hose, so there is no stress whatever during pumping; just a little while putting the head on and off the stem and operating the locking lever.

I would willingly pay a premium for tubes which had superior valve reliability.

Quoted post said:

Originally Posted by alienator

I also bin the washers. Some I do keep as potential fixes for something else. I've never done damage to a tire because the washer wasn't there. Michelin tubes, with smooth stems, show that you don't need the washers, and as it happens, they're damned fine tubes.

Agree. I've been working in a Trek shop for almost six years and I've been using Bontrager tubes almost exclusively. They're probably made by CST, like a lot of other rubber bicycle products.

We install the nuts and dust caps on the customers' bikes, though.

Don't push the valve chuck on so hard, pull it off carefully, and if your rim is drilled for Schrader valves, that's what you should use.