lanfarm

Hey look, its me again Here comes some more beginner questions. Here I go:

Today I was training for the triathlon im doing later on and my back wheel went flat randomly. I must have ran over some glass or somthing. So now I need to figure whether i need to replace my tube or the tire. I dont expect my tire to be popped but the tube might be.

1. How do I find out whether my tube, tire or both has somthing wrong with it?

2. What kind of tubes should I get? Is there a difference? https://www.remysport.com/2007/parts.asp?search=pp-10-4
Press the link and apparently thats what my LBS has in stock. Which ones should i get, there isnt very many choices.

3. The flat is on my rear wheel. It has a quick release, but i dont know how to take it off because i am afraid of doing somthing to the derailer. How should I take it off?

Cheeto

Just undo the quick release, and pull the tire up and back a bit, and undo the chain, the you wont hurt the derailure at all..

Go with the bontrager tubes.

Cheeto

check your tire for any sharp objects also.
remove said object if it is in there.
also check your rim to see if any of the spokes are poking through the rim tape.

cyccommute 

A slick way to check for sharp objects in the tire is to use a cotton ball and rub it around the inside of the tire. The cotton will stick to the sharp object and leave a little indicator. If you use your fingers, you can cut your fingers on the sharp bit. The cotton ball avoids all that.

Cheeto

Cutting your finger adds charcter, and it make you 100% positive something is in your tire.
lol

Cornercarver78

the wheel will also come off and go back on easier if you shift to the smallest cog.

lanfarm

I pulled the wheel off safely
I even tried to put it back on to see if i could. I can!
The bontrager tubes eh. Alright.

lanfarm

Once I pulled the wheel off, I took off the tire and took the tube out. I got a pump out and tried to pump air and found the leaks because the air was coming out. I also checked the rims and nothing was poking out as I could see. I dont know if there is somthing wrong with the tire.

lanfarm

Ha, this is a ingenious way. I used it and I found nothing. Is it poosible for there to only be a leak in the tube?

lanfarm

Yup, did this by accident because I was on that gear already.

Cheeto

yes you can just have a leak in the tube. unless its a tubeless UST tire, then the tube is always what is loosing air.
buy a new tube and you'll be fine

cyccommute 

It's a puncture but whatever caused it may have fallen out or been pulled out after you rode over it. It happens often and just leaves a hole in your tube. But it's always best to check before you put another tube in there...unless you really like fixing flats

lanfarm

Lol, of course i do. This is the first time so its a learning experience but its not somthing i want to do everday. The sad thing is ive only had the bike for about 1 week and it already flatted on me. Whatever, im going to the LBS tomorow so they can fix it up

Cheeto

lol I got a flat my first ride.
Welcome to the sport.

lanfarm

Why thank you

cyccommute 

Have them show you how to change a tire and patch a tube while you are there. And get a pump! I'd suggest tire liners (unless this is a tubeless) of some kind too. Flats happen. Best to know how to deal with it or buy some really comfortable shoes cause walking 5 miles pushing a bike is no fun at all

rydaddy

Is something wrong with patching? A spare tube is great for changing a flat on the trail but don't throw away a tube after 1 flat. Patch it and reuse. Also, Bontrager are not the only tubes out there. Personally, I like Specialized thin.

lanfarm

Bontrager is pretty the only brand of tubes on the website. And patching i could do but I dont have a kit or anything.

lanfarm

I already know how to patch and change a tire. I just need a patching kit or a new tube or tire. And i have a pump. But its one of those electric ones; not very portable. What does a tire liner do?

Chris_F

Assuming you use traditional tube/tire combo (and not tubeless, a totally different, somewhat exotic animal)...

Here's how it works: the tube holds the air, the tire holds the tube and does the whole ground-contact thing. It helps to understand this interaction a bit. Pump up a tube on its own and it will get bigger and bigger (like a balloon) but the pressure won't go up much. Put that tube in a tire and the tire forces the tube to stay small and pumping more air increases the pressure in the tube. The tire/tube acts as a system. A loss of pressure is ALWAYS a result in a leak in the tube, but the tire may play a part.

I've had flats for only two reasons: something punctures through the tire and in to the tube, or the tube is punctured inside the tire. Two ways the tube can be punctured inside the tire: something in the tire punctures it, or it gets pinched by the tire itself.

Let's cover the punctures: Obviously sharp stuff can puncture thrrough the tire and pop the tube. If that happens you'll need a new tube but you'll also need to make sure the tire doesn't still contain the sharp thing or else you'll put in a new tube and it'll just pop again. Check the inside of the tire and rim thoroughly to make sure there's no stuff in there. I keep track of where the tire aligns with the stem on the tube and when I get the tube out I pump it up, find the hole, find the place on the tire corresponding to the hole, and check to see if something is poking through. I then check the entire inside surface of the tire and rim before putting in a new tube.

Pinches can happen for two reasons: you don't get the tube fully inside the tire and it pinches between the rim and the tire, or you hit a bump without enough pressure in the tube and the tire squeezes the tube as it gets mashed in to the rim. The first will result in a flat fairly soon after you air up the tire, so make SURE you get the tube fully in to the tire and not caught between tire and rim. The second happens because you run too little air pressure.

So let's talk about pressure. Most flats happen because of too LITTLE pressure, not too much. So if you want to avoid flats (impossible but a noble goal) the best bet is to run as high a pressure as possible. This will reduce grip and give a harsh ride so it's a balancing act, but it's best (flat wise) to err on the side of too much pressure.

When do you need a new tire? When it no longer does the job of holding the tube in. If you add air and the tube bulges from the tire then you need a new tire.

Cheeto

trying to keep it simple.

Was going to get to he patching next, I NEVER said THROW away the tube.

ANd on the website, Bontrager is the only GOOD tube there.
which s what his LBS has in stock.
I know that bontrager is not the only tube out there.... I use many different brands.... which ever is cheapest at the time lol.

lanfarm

Wow, that was very comprehensive. I think mine broke because of a pinch. The problem im having right now is finding a good pressure. What is a good tool that can read this and what should I get?
Also, today after I bought the tube from the LBS, deciding that I would put it in myself to learn, I did it all well but the most troublesome thing is to get the brake thing back on.(I took the wheel off) Is there a easy way to do it? It took me like, 20 minutes.

Zephyr11

What makes Bontrager tubes better than any other tube? I use Continental Lights because that's what my LBS has and they're small and fit in my pack easily, but I'd just as soon use Performance brand ones. I guess they might be a tiny bit heavier than the Continental Lights I use now, but eh, I still think a tube's a tube.

I don't think anyone mentioned this, and it might be totally common sense, but I'll point it out just in case. Make sure you buy the right kind of tube. If your valve is skinny and has a piece to unscrew before you can fill it with air, be sure to buy a Presta. If it's fat, buy a Schrader.

As for a pump, I'd invest in two. A mini pump to throw in your Camelbak/on your frame, and a floor pump because mini-pumps suck when you're at home. Most floor pumps will have a gauge on them to tell you the pressure. You might consider picking up CO2 cartridges for your tri, since they're fast.

What kind of brakes do you have? If they're discs, just line up the rotor with the brake. If they're V's, I've found the easiest way is to push over the little accordion thing, and then grab the outside leg piece with one hand and the noodle with the other, push the leg and pull the noodle towards each other, and then flip the link up so the end of the noodle goes inside of it. At that point, you should easily be able to jiggle the link and noodle until the end pops out.

Also, when putting the tire back on, if you line up the graphics on the tire with the valve, it'll make it easier to search for crap in your tire if you flat again.

Finally, instead of tossing that old tube, wrap it around your chainstay in ziptie it in place. Now you have a nifty chainstay protector to eliminate chainslap.

Chris_F

My bike pump has a pressure gage built in. You may be able to find a stand alone pressure gage at the bike shop. If not get an adapter and use a regular car pressure gage.

The brake thing shouldn't be that hard. Don't know why you'd have trouble with it. Hold the brake closed with one hand and flip the little catch-release thing with your other hand.

lanfarm

The catch thing can barely reach the thing that holds it on. I needa pull it as hard as possible and do it.