mrchristian

The cheap wheel from my Motobecane seems to have developed a taste for inner tubes. I initially figured I was installing them wrong as they seem to blow up at the valve stem (kind of like a cut). Everything looks fine...the tire seats right in the rim, the rim strip looked alright and the valve was nice and straight. I don't use any tools to mount my tires, just my hands. Lame, considering that I have been installing tubes since I was a kid.

After a couple tubes that didn't make it overnight, I gave up, sucked up my pride and took it to a LBS. The wheel pretty much baffled the mechanic. He blew up 3 tubes in the store trying just about everything to make it work. Velox rim tape, different brands of tubes, checking the tire multiple times. Finally he gave up and told me I was out of luck. He was nice enough not to charge me either. This is the second tire its done this with (a blow out claimed the life of my first tire) so that's not the issue either and the tire I have (specialized all-condition) is probably less than 2 months old with maybe 100 miles.

For the record, its just a ****ty single wall rim (alex RP15P if that matters) and i've run my hands through it a couple times and there is no sharp objects or anything like that. Satan rim?

If I'm SOL (unless you guys can come up with something), I probably need to replace the rim. The store didn't have a replacement handy (just high end stuff) so i'm wondering what you guys suggest for a cheap rear wheel ($100-150). I checked out all the regular online stores, and there wasn't too many things that popped out as me as appealing. Anybody sell entry-level Mavic stuff (single wheel)? The excellent wheels on my cannondale rush converted me.

Retro Grouch 

Are you getting cuts right at the base of the valve stem?

When they make rims they bend the extrusion to form the hoop then they put it on a machine that punches all of the spoke holes and the valve hole at one time. If the valve hole punch gets a little worn it can leave a burr. My guess is that is what is causing your problem. If it was my wheel I'd try using my dremel to smooth the valve hole.

StupidlyBrave 

I have a rim that does this as well.

I cut a one inch square piece from an old inner tube (sounds like you have one ) and make a small slice in the center (maybe 3/16 piercing). Then slide onto the presta valve before mounting in the rim.

I think that in my case, it is a case of the inner valve hole being just a little too big. When the tube is under pressure, it doesn't have enough rim to constrain it and the valve migrates too much into the hole.

Gee3

Performancebike.com has Forte wheels that are very reasonable. They won't win any best of show awards but I believe Perf bike has a good warranty or return policy. Or try your local Craigslist.com.

Stoopid question, but did you check the inside of the tire for any burrs?

Good luck!

AEO

how about stuffing a rubber grommet from the HW store? I know size 6 or 8 would fit nicely on presta valves.
I had to do this because some genius thought it would be nice to drill out to schrader size

cuski

https://www.chainreactioncycles.com/M...?ModelID=12855

Add cca. $20 for shipping.

Terror_in_pink

file down the opening.

ericm979

Look at the punctured tube(s). Find the puncture. If it is on the rim side, the problem is with the rim. You can line the tube up with the rim using the stem to find the place on the rim where the problem is. Don't forget to try it both ways (i.e. if the puncture is 6 inches from the stem, look 6 inches to the right of the valve stem hole AND 6 inches to the left). All it takes is a little fold in the rim strip.

If the puncture is on the tire side of the tube, then you know its the tire. I have had very small bits of glass or steel embed themselves in the tire where I could not find them without matching the tube up to the tire in the same manner as I describe for the rim. That's why I mount all my tires so the label is next to the valve hole on the rim. If you didn't do that, then you can often find small embedded stuff by carefully looking over the tread while pinching it together. That opens the cut so you can see the object. Also try running a thumb around the inside of the casing, sometimes that finds it.

Youngin

edit: probably should've read the thread, still haven't. Rim tape is what first came to mind here.

JayC

Prolly not spoke hole related since you said they changed rim tape but you could put Veloplugs in the spoke holes. I put them in all my wheels and they've been great. If they dont quite snap in (A little loose), you can glue them in.. theyre still easy to remove if need be.

operator

Oh please. Why does nationality even have to play into the quality of ones products. Alex makes some good rims, and they also make some **** rims. Guess which ones you have?

Thanks for playing.

Oh and, deburr the valve hole is the solution. Thanks.

rooftest

Where is the hole in the tubes?

Spiduhman

Uhm, did you bring the wheel in freshly hosed condition to LBS so he/she could "gather it all in?"

Is it the front wheel?

I've found that some tires actually rotate around the rim and jam the valve, eventually ripping the tube just a bit at the base, usually only on the front, which gets force mainly in one direction, from braking.

The presta, with the lil' jam nut, doesn't lean over in dead giveaway, like Schrader...

The heavier cloth tape gives the tire something to "grip" on, but makes changing a bit tougher than the superthin rimtape.

Line up that label just so, and watch it to see if the tire is rotating; my mtn front does, even with the cloth tape, but it's very much less than with the tape I used to use... but, I have to carry a tyreiron now.

Spiduhman

Is your tire rotatin'? Is it the front only? If so, ...try not using your front brake (be careful)?

Didja change to a grippier rimtape?

jkizzle

+1111122134124

my cheap bike direct-esque wheel ate tubes too till i put some rim tape on, and havnt had one in 4 months of sloppy, sloppy commuting and one wreck. I am guessing the rim probably has crappy rubber rim strips?

62vette

Different rim tape is not going to stop a tyre from rotating on the rim as the tyre and rim tape will generally not be coming into contact with one another.

Some of the non-adhesive rim tapes will move and expose the sharp edges of spoke holes which will definitely cause punctures. I'd definitely install adhesive rim tape.

If your tyres are rotating on the rim, you're either not inflating to a high enough pressure, or the tyre you are using is just not right for your rim, which does happen on occasion. Make sure your tyres are inflated to within 10psi of the max indicated on the tyre.

Spiduhman

Looks like OP is having better luck!

No and no, however (In my particular case) to the points above:

1) My front wheel rimtape has black smudgly marks where the bead is touching the rimtape; it does make a difference.

2) No way am I running 55 lbs in my 2.1 fat knobbie front mtn bike tire! I'm over 200 lbs., and, for me, 25-30 in the front, and I don't have pinchflat problems, thank you very much. I run no more than 40 in the back. These pressures suit me and the conditions where I ride. Ten pounds under max? Harsh and dangerous.

I'm running Ritchey OCR zdisk wheels, Hutch Scorpion on the front, and Mythos XC rear specific on the rear. In my case, the cloth tape makes all the difference on that front wheel.

The Mythos leaves hash marks on the rear wheel rimtape, but I use the thin stuff there - easier to mount/dismount, and I'm not having rotating issues in the rear with the Mythos.

You said "...generally not in contact..." - o.k. ...

62vette

I was not thinking of MTBs in my statement. This is the road forum after all. MTB tyre pressures are more about traction than punctures.

You will get more flats on a road bike if you don't run enough pressure, and the more you weigh, the more pressure you should run.

Spiduhman

Oops, yeah.

Spiduhman

Huh!

Tire way too loose, eh? How about that! Couldn't be that your tire was TURNING ON THE RIM? Who would'a thought of that?

Nah, could't be, because

It's a ROAD bike bro...



Congrats on your new wheels!

I replaced cheap Mavics with Ritchey OCRs on my mtn bike a while back - not a top o' the line wheel, but a big improvement nonetheless.

From there, I've learned that maintaining proper tension is important! ...not just for performance... if you want your wheel to last, do the maintenence.