Scott Aspect Problems! HELP!
 

I'm a new biker and my girlfriend and I both purchased brand new Scott mountain bikes. She has the Aspect 50 and I have the Aspect 60. We love the light weight frames but we've had the bikes for less than 2 months and have had tubes blow between us 7 times, out of 10 trips on our bikes together.

My rear tube has gone flat 3 times, 2 in one day! We don't ride them rough - yet! I keep having to take them into the dealer who is now putting some cloth rip strips to try and prevent this from happening.

Has anyone else had a Scott Aspect with this problem? The tires are the standard Ozon 2.0
Any suggestions out there to try? The dealer inspected the rim and tire today and told me it didn't seem to have any problem. Is it common to have so many blown tubes?!? It's frustrating! I need help!:mad:

I'm moving this to Bicycle Mechanics (from General Cyclin discussion).

Have you checked you have enough pressure in the tubes? When you hit a bump, underinflated tyre compresses too much, and the tube gets pinched against the rim. These are called pinch flats or snakebites, and are fairly easy to spot because they usually result in two small holes close to each other. I would imagine your dealer would have noticed by now, if this was the problem. Nevertheless, make sure you inflate the tubes up to the suggested pressure (it's printed along the outer tyre wall).

Pinch flats aside, all repeated flats that I've ever had have resulted from something sharp (a small piece of glass or sand) lodged in the outer tyre and then slowly working its way through the tyre towards the tube. Next time you have a flat, make sure you (or your bike shop, whichever fixes the flat) know where exactly the puncture is in relation to the rim/tyre. That will tell you whether to look at the rim or rim tape, or the inner surface of your tyre. It will also tell you where exactly in the rim or tyre you should look at.

Finding the culprit in the outer tyre is difficult unless you know the exact spot. Even then you may not find anything wrong on the inside of the tyre, but looking at the outer surface you'll see a small cut where the sharp piece entered. If there's something wrong with the rim or rim tape, that's usually easier to spot. Still, it helps to know where to look.

--J

First I'd say - learn to fix your own flats. It doesn't take much of a ride into the wild blue yonder before having to walk back becomes a real nuisance. Next, having tubes blow is a fairly generic description.
Chiming in with Juha, you really need to figure out what's happening. Punctures due to something stuck in the tire will reappear in pretty much the same position WRT the valve if you keep track of the orientation of the tube.
An old tip for finding elusive slivers is to run a cotton wad along the inside of the tire, it can snag on stuff that your fingers might have missed.
Snakebite AKA pinch flats, well, these rarely come as a complete surprise. It's a distinct feeling when you bottom out on the rim.
A pump with a manometer is good to have, inflate to recommended value on the tire sidewall. Getting pinch flats w/o noticing while running at recommended pressure is quite unlikely.
Flats due to rim strip shifting does happen, and it's either down to really poor rim strips or to overinflation. Again, a pump with manometer is your friend. Do note that severe temperature changes can cause enough of a pressure change to be the difference between tube blowing out or not.
IME those flats are usually easy diagnose, you can see the change to the rim strip, and you can even have an indentation around the actual puncture where the tube has bulged between the inner/outer wall of the rim.
Flats due to tube getting pinched at assembly also happens, but if you're in the habit of having the LBS deal with flats you're either amazingly unlucky or have a really sucky LBS.
I went through a series of flats some years ago due to a folding tire that was a loose fit to the rim. Unless properly inflated the tire would shift on the rim while braking, eventually tearing the valve off. ALso something the average LBS should be able to spot easily enough.

Thanks for your help... but I'm still having problems...
To give you more details... I have changed some of my flats when I'm stuck out somewhere... the dealer I bought from changes them when it's possible, so there won't be any excuse to blame me for improper tube installation, even though it isn't very difficult if you go step by step.

They installed cloth rip strips on both bikes and we took them out this weekend. Saturday I rode around for a couple hours, no problem. I got home and checked tired again before going to bed. In the morning it was flat. I took out the tube and it was approx. 1/4" tear in the tube, facing the center of the rim. I measured the tear from the stem and it is exactly at a point where the spoke connects through the rim. AND I could already see another worn spot on the tube in the exact area of the next adjacent spoke/screw.

So, I changed the flat, marked the spot where it tore and rode Sunday for 2 hours, came home and everything was OK. I was sitting up doing some work late at night and heard it suddenly releasing massive air, bursting in the hallway. I took out the tube and it is at the exact same spot as the first and again, same size tear.

This makes the 3rd front tire tube on my bike that's blown in the 2 months I've had it. I've had 3 blow in the rear. 6 just on my bike in approx. 12 trips out. I always inflate to the standard pressure before going out. I had a cheap $70 bike from Academy that I never checked inflation every trip out and rode through woods, gravel, etc. with never a problem. My girlfriend had a road bike that she would even go off road sometimes without a single flat in over 10 years!

If you look at any company who tests their product and it fails 50% of the time - it would be considered a defective product. I took the rim and tubes to another dealer and he was stumped, saying usually one rim strip should fix the problem but I could try two strips or look into warranty issues for defective rims. Every tear I've had is either on the edge of the rim side or center on rim side, never on the tire side. It is never a two hole puncture but a small gash.

I've been looking into the tubes and even though they are not the best rated ones out there - both dealers in my area carry them as their main stock tube - the same ones that GIANT sells - Kenda. GIANT dealer here seems to think it isn't a tube problem but something with the rim. I'm hoping they will not give me too much hassle in replacing the rims, if that's the problem here. I've had bikes since I was a kid and never had a tire problem of this nature. I just started riding mountain bikes less than a year ago and my main reason for contacting experienced riders on this forum was to see if this was common in mountain bikes or anyone owning a scott aspect 2010???

Out of the six tubes I've had blow - I changed two of them on the road. All I wanted was a bike I could rely on. It is really depressing having to do this over and over again. I did fork over cash for the first few blown tubes we've had. The dealer is trying to help me get to the root of the problem and installed free rim strips and free tubes. I'll post whatever results I end up with. I hope it isn't an ad for anyone interested in a new bike! HAHA!

You have a rim/spoke/strip issue. I find it hard to believe that your shop can't find the problem since you are able to find the actual spot where it happens. To me it sounds like you have a spoke sticking too far through the nipple, or a sharp edge on the rim that isn't covered by the rim strip.

Good luck, but push your shop to solve this.

Is it a single-wall rim? Seems unlikely, but who knows?
If that's the case, then it gets real critical that the spokes don't protrude beyond thew nipples. If they do not even a cloth rim strip will do much good.
If it's a double-wall rim (far more likely) then a cloth rim strip really should sort it out - if installed correctly.
I've had tubes blow on non-woven rim strips due to overpressure causing the strip/tube to bulge down onto the spoke, but never on cloth rim strips.

Update2
 

Well, after riding the bike Sunday and getting the 2nd flat that night - I took the front rim, tire and 2 tubes to the dealer and he's been looking into the problem. This morning I was in bed and suddenly heard the fsssttt! sound of air blowing! Oh, no! I got up and sure enough my back tire was now flat. It had sat, upside down, for three days and suddenly blows. I took off the tire and inspected the tube. It has a small puncture tear on the center rim side near the stem where a spoke nipple sits. And there's even a good indention on the next spoke nipple area on the tube where it looks like it was wearing down!

I have velox cloth rim strips and they don't seem to be helping! I'm going to take the back wheel in today and talk to the dealer about double-walled rims and double rim strips on each rim, maybe cloth and rubber combined. My rims currently are single-wall.

Seeing that my girlfriend had some problems with her wheels, I'm wondering if this edition of Scott Aspect has rims that are slightly defective, meaning the ones who manufacture the rims, the actual detailed specific mechanical design of these rims are slightly wider than others, allowing more pressure on the tubes pushing against the rims, whereas other rims may be more narrow?!? At this point I'm not really sure. It could simply be my specific rims having some mechanical defect. She's blown 3 tubes and I've blown 7... since she got cloth rim strips, her problems seem, so far, to have ended.

I don't notice any loose spokes on either of my wheels and the nipples on the areas where the tears and puncture have occurred doesn't look or feel much different than any other spot on the rim. All the spoke nipples, of course, protrude slightly up from the rim...

Anyway, I consider the entire ordeal a bit humorous when I owned a $70 Academy Ozone that never had a flat and here I am with my first bike on the higher end and all I seem to be doing is taking it into the shop! Haha! Oh well, I hope I can figure this out or the dealer will cut me a deal on some double-wall rims!

- madmanstan

That does make what you are experiencing less improbable. Cloth rim strips are usually helpful on double-wall rims, as they bridge over the access holes for the nipples better than anything stretchy. But they won't be anywhere near as "special" on a single-wall rim, what you need there is basically padding to cover the nipples.

As it's a bike bought new from a dealer it's really his problem, and he should be able to sort it out. Some things comes to mind though, maybe the wheel is built with slightly overlong spokes? that would have the ends of the spokes poking through the nipples causing pointy nubs. If this is the case one can either rebuild the wheel with slightly shorter spokes, do a bug-ugly fix and stick a washer under every nipple or simply grind off the protruding nub of each spoke. The latter is almost as bug-ugly as the washers(but faster with an angle grinder) as it might have to be repeated if the wheel has to be trued/re-tensioned, but still a doable solution.

Not likely. First off rims do vary in width, and I've never heard of that causing a problem for the tube before. Secondly, the tube has almost zero structural integrity in itself, it'll simply stretch to fill whatever space there's available for it.

What one would first think of in that case is a burr somewhere that'd be poking holes in the tube, which either you or the dealer ought to have spotted by now. Possible, but very unlikely is that your rims is a tad off spec, which allows for more spoke protrusion than otherwise.