dprayvd

...any longer! I've been plagued by rimside punctures (better than 10 now in many fewer weeks) and the lbs people say "your propretiary rimstrip" looks without flaw. I'm gonna place 26" tube cutout rimstrip on top of them. I don't care. I don't.

blaaarrrgghhhhhhh!

jimc101

You need to find the what's causing the punctures, just adding another rimstrip may not resolve this. Are the punctures in the same place all the time? are there any other common factors to them.

FBinNY 

Are you getting punctures, or splits? same place each time or random? near the valve or elsewhere?

And now for the $64 question. are you riding narrow rims. If so, read my earlier post on a prior thread dealing with the same issue which is becoming so common maybe they should have a sticky about it.

BTW- if a bike shop can't solve rim side punctures in 2 tries (maybe three) you not only have a tire problem, you also have a bike shop problem and the fix might be to roll that wheel to a better shop.

fleisc66

It is definitely strange to keep having that happen. I would pull off the rim strip and and give the inside of the rim a look over. There may be a burr in the metal around a spoke nipple hole or other place from manufacturing. I have also seen the slots on the backside of nipples damaged so that they have sharp edges from the tool slipping during assembly. I would take a small file and carefully cleaned up any sharp imperfections that could penetrate the rim strip and tube.

FBinNY 

If you can't see or feel a burr or edge with the rim strip on, and the rim strip is intact and in place, then anything under it wouldn't cause problems, since the tube can't be punctured by what it can't come in contact with. That's why you use a rim strip in the first place.

The OP has to look for something that could cause problems with the rim strip on, or possibly something wrong the rim strip itself. Otherwise it might be the tire if the tube is installed with a twist, but the shear number of repeats contradicts that theory.

In order to identify and solve the problem, the OP has to use Occam's Razor, and develop a theory consistent with what's happening and look there. Fixing things that aren't causing his problem won't solve it.

dprayvd

Rim is a Bontrager SSR, paired spoke.

Tire/tube installation is ruled-out.

The puctures are small random splits smack-dab in the center of the rimstrip, rear rim, with no identifiable source.

The rimstrip (the red Specialized nylon set-up) edges are not sharp, and they worked without issue on a previous wheelset.

The rim surface is very clean, so I'm thinkin' (all along) defective tube. Two, actually.

Pissin' me right off.

Anyway, I placed the beforementioned mod, so bade me luck!

dprayvd

FBinNY, spot-on to everything you stated regarding narrow rims and rimside punctures. I do all that except having a higher-quality tube. I'm using fresh standard Specialized tubes in the 48mm stem length.

Would you offer a suggestion as to your favored tube for this application?

Oh yea, I'm running 28mm tires, so that right there is the cause. I'm sure of it now, having read your post. I wonder how I missed it, its being so recent and all.

FBinNY 

I can't recommend any one brand tube over others, though I've had better luck over the years with IRC or Kenda, among the non-premium tubes. The problem is that with tubes (other than those that say IRC, Kenda, Cheng Shin and a few others) you never know who made the tube, and what quality options the importer paid for.

I used to import IRC tires and tubes and the list of options each costing fractional pennies per tube are staggering. the "same" tube sold under the various brands can be very different.

In your shoes, I'd buy the largest tube that fits, like a 28-35 rather than a 23-28. I'd also open the box and look for one that actually measures 21mm or so across folded flat (42mm circumference uninflated). You have to check because there's only marginal correlation between the marked size and the actual size.

Then before installing the tube inflate it to about 40-50mm to stretch and relax the rubber. This is also a good quality test. Good tubes will inflate fairly evenly while cheap tubes will inflate like cheap balloons, stretching to 2-3x their diameters locally while the rest in unstretched.

When installing, use lots of talc so the tube can slip within the tire. Inflate to 10-20psi, and squeeze the tire sort of massaging it so the tube can blow down into the rim and equalize the stretch. I honestly don't know how effective this is, but friends following my advice have had success when all else failed, but then again it might simply have been the size, quality and pre-stretch that did the trick.

Good luck.

BTW- I'm serious about the bike shop if the shops mechanic installed multiple tubes unsuccessfully.

Sundance89

OP, I strongly believe it is your Specialized tubes. Please read thread. I decided to post it clean as a warning to others. (This is my experience as well as others here in Scottsdale, and now perhaps yours too.)

Warning: "Strongly Possible" Specialized Tube Defects

dprayvd

Sundance, The splits are not along a seam, but still, they are linear enough to indicate the "hyperstretch" FBinNY is putting forth. So close enough a "seam" for me.

AND...and, I just went to move my bike and alas, the rear again is flat. This split, rimside and linear to all its friends (and on the other tube that I mentioned before being that the orignial perp is curing), happened just under the orange edge of a Rema patch, right where the patch begins orange to black, but this time with a nice smooth talced full-width rubber layer underfoot. Gotta be the tube(s).

And these five fresh tubes I have all do the "Cheap Balloon," as coined by the FNinNY! In fact, all my past tubes (always use/d specialized) have done this, to some extent. Fack!

I'll see about the Q-tube

I'm gonna get larger tubes.

My thumb skin is gettin' sore.

dprayvd

FBinNY, how does one determine factory of origin?

dprayvd

I'm good with my LBS. They're good skilled people/wrenches and will make it right if I ask (as in replace the tube/s, or whatever consumable is at issue).

They did not do the installations, only looked at the rimstrip and saw no flaws, as did I. Sorry about that ambiguity.

dscheidt

The talc isn't going to let the tube move relative to the tire. It was used in automotive tires to keep the tube from vulcanizing to the tire inner liner. That's not a real problem with bike tires (though I've seen it where much too large an area was covered in vulcanizing fluid for a patch, and that sticks to the tire casing. Usually fatal to the tube.) because there's simply not enough heat for the reaction. That's also why the insides of tubes are filled with talc, to keep them from sticking to themselves when they're packaged hot off the tube line.

With automotive and industrial tubed tire mounting the process is to inflate the tube to seat the beads, and then completely deflate it, which lets twists and position problems work themselves out. Then you reinflate to working pressure. I do the same on bike tires, making sure there is no tube caught by the tire before deflating.

FBinNY 

As I said in the original post I wasn't sure how much difference it made, if any. But I have found that my powdered tubes were less like to adhere to the tire wall after months of service.

I rank powdering tubes into the "doesn't hurt, might help" category, and do so if it's convenient, for example tubes replaced at home, but not those replaced on the road. My standard for things in this category is very low, so I also take low dose aspirin daily (male above 60 yrs old), mega doses of Vitamin C when I have a cold, and other similar actions, not really expecting a big difference, but in case there might be some improvement. FWIW- I've never had a cold lase more than 3-4 days, so either Vitamin C helps, or I've been lucky, but for the $1.00 I spend on the "cure" I won't stop.

davidad

Velox rim tape.

noglider 

Using Velox rim tape fits into FB's category of "might help, can't hurt" things. It costs about $3.50, and there is no better rim tape. Sometimes, it DOES solve problems like these. It did for me, just this week!

dedhed

I had a run this summer of splits right at the valve rimside on some 700 X 18-25 Kenda tubes. New Mavic open pros, 25C tires, Velox tape. I put another narrower strip of velox over the other one thinking it might help - it didn't. I chalked it up to tube/valve quality and bought something else.

FBinNY 

You as a consumer can't, except when buying tubes marketed by the actual maker. The list includes IRC, Kenda, Cheng Shin ( Maxxis), Innova, Lee Hsin, and one or two others. When you buy a Trek, Specialized, Giant, Raleigh, etc. tube you have no way of knowing who actually made it, nor if the importer was sourcing from the best or cheapest possible vendor.

The tube makers offer clients a long list of options, including exactly which valve, whether the tubes are pre-tested (last time I imported this cost USD 0.75/tube) meaning inflated and kept that for 24 hours, and other minor stuff.

The importer also decides what size markings will go on the box, and which size tube will go into it, so different brands will use different numbers of tubes to cover a given width range.

I'm not importing tubes any more, so I have to deal with what's available, and bring my ruler to local shops and measure and check tubes when buying for my commuter. My other bikes or on tubulars so I'm spared some of the grief.

All I can suggest is that once you find a brand that seems OK you stick with it and hope they don't change vendors.

FBinNY 

It sort of does, but it does hurt to the extent of $3.50. If the OP has inspected the rim strip and it's intact and covering the nipples or spoke wells, and any rim flaws, it's doing 100% of the job and you can't improve on that.

mrmusicmr

what do u want to buy?

dprayvd

My experience with Velox is that, over time, it creeps and bunches.

The creeping lead to exposed spokehole edges and flats (a particularly phat one on the front at speed). I'll concede I used the narrower Velox, but still, it crept.

The creeping/bunching lead to ridges in the tape and flats. This was the wide Velox.

*Most of the flats were the "go out into the garage and there's a flat" flavor. Regarding flats, I prefer this.*

That's why I went with the Specialized rimstrip.



The velox was installed onto a clean surface with adequate surface contact/tension.

I'm staunchly in FBinNY's camp. It's the uneven stretching. So, lotsa talc and a "brutal" 25psi massage.

Regarding the OP, no decompression going-on two days (but I've not looked this morning). This is better.