Tire is always going flat. What am I doing wrong?

Joined
Jun 29, 2017
Messages
63
Hello all,

My rear tire on my Huffy Cranbrook always goes flat no matter what I do. I bought Goodyear thick bike tubes and put slime in them so if there was ever a hole the slime would fill it. However, even for small thorn holes, the slime never seems to seal them and I'll come back out in the garage hours later and it's totally flat. I even put the recommended amount in both of the tubes. Both tubes have 700 miles on them and the back one has had 13 patches put on it and half the tube was made of patches so I threw it away and got a new one while the front one has never had a hole. I'm afraid once I put it on it will just end up getting a hole within a few days. It has stranded me 2 days ago and it took me over 3 hours to walk it home. I even had the CO2 inflator and it ran out of air in minutes. The tires say "Inflate to 40 PSI" and that is all they say. It does not say that is the max amount or anything. I have a 66cc engine on the bike and I weigh about 195 pounds.

I have noticed when I sit on the bike the rear tire flattens out on the bottom despite being inflated to 40 psi. The tire size is 26" x 2.125 and they are cruiser tires. Can I inflate it over 40 PSI to maybe 50 PSI? I just feel like it needs more air because it flattens out at the bottom of the tire because of all the weight on it. The middle of the tire tread is starting to wear on the rear.
 


Lukesky36

Active Member
Joined
Oct 3, 2018
Messages
368
run your hand though the rubber tire there is probably a thorn sticking though on the inside popping the tube if that isn't it get some electrical tape and run it around the rim for 2 or 3 turns should be enough. should fix it just take your time and massage the inertube in when you install one take your time fill it up 50% and bounce it gently on all sides and that will level the tention out on the inertube and fill it up the rest of the way anyway the goodyear tubes are pretty bad i had one blow out on me for no reason they are kinda trash in my experience just stick with the cheap skinny tubes
 
Joined
Jun 29, 2017
Messages
63
run your hand though the rubber tire there is probably a thorn sticking though on the inside popping the tube if that isn't it get some electrical tape and run it around the rim for 2 or 3 turns should be enough. should fix it just take your time and massage the inertube in when you install one take your time fill it up 50% and bounce it gently on all sides and that will level the tention out on the inertube and fill it up the rest of the way anyway the goodyear tubes are pretty bad i had one blow out on me for no reason they are kinda trash in my experience just stick with the cheap skinny tubes
Yeah there are no thorns I patched it last night and it went flat again today. I found a new thorn poking through that I must have ran over. I'll try electrical tape over the rim liner as well. Would more air make the tires harder and make it more resistant to having thorns go through it? Would going over 40 be okay?
 

Lukesky36

Active Member
Joined
Oct 3, 2018
Messages
368
Yeah there are no thorns I patched it last night and it went flat again today. I found a new thorn poking through that I must have ran over. I'll try electrical tape over the rim liner as well. Would more air make the tires harder and make it more resistant to having thorns go through it? Would going over 40 be okay?
more air actually makes it easier for thorns to go though i wouldnt go 40 untill you did a shake down for a while untill you know the tire isn't going to blow out on you
 

darwin

Well-Known Member
Joined
May 26, 2008
Messages
3,022
Usually, max on that size tire is 65psi, look on tire sidewall to be sure. I normally run those at 60 psi. OP you need to start from scratch, new thorn resistant tube, Tuffy tire liner and a Kevlar lined tire. you will no longer have flats unless GOD personally zaps yo tire.
 

The_Aleman

Well-Known Member
Joined
May 2, 2007
Messages
876
Max tire pressure depends on tire construction, a 26x2.125 tire that says "inflate to 40 psi" is a generic tire, just fine for normal bicycle use or a sub-30MPH cruiser. From my experience, 60-65psi is ideal, because low-pressure balloon tires will "walk" all over the place under hard cornering with a heavy load, sometimes causing pinch flats on hard bumps. A higher-pressure tire also tends to ride faster and wear longer.

I've been using Slime for over 25 years on all of my bikes and I swear by the stuff, although it has quirks*. It doesn't do well with punctures caused by spoke heads. You must make sure your rim's spoke heads are covered well. My method is to put 2 wraps of PVC tape over the center rim strip and then put the rim strip over that. Rim strips can move when inflating thick tubes in normal-sized tires. Tire liners can be troublesome with thick tubes as well, and I have seen tire liners cause flats themselves.

And finally, making your tires as heavy-duty as possible usually just makes them heavy. Nothing slows down your bike quicker than heavy wheels and tires.

* Slime quirks
It doesn't work well on patched tubes. It will cause the patches to separate from the tube. Do not patch.
If you get puncture(s), refill tire and keep that wheel spinning. Air up again and keep it spinning as needed.
Never inflate tires with the valve stem at a lower position. Air up tire with valve stem at between 10 and 2 o'clock.
A Slime'd tube may lose it's puncture seal(s) in direct, hot sun. Slime also does not like temperatures below 20F.
You may find that your bike is a bit slower to accelerate and slower uphill with Slime.

Lightweight alternative:
Michelin Protek Max tubes + Kevlar tire or Kevlar tire liner
 
Joined
Jun 29, 2017
Messages
63
Max tire pressure depends on tire construction, a 26x2.125 tire that says "inflate to 40 psi" is a generic tire, just fine for normal bicycle use or a sub-30MPH cruiser. From my experience, 60-65psi is ideal, because low-pressure balloon tires will "walk" all over the place under hard cornering with a heavy load, sometimes causing pinch flats on hard bumps. A higher-pressure tire also tends to ride faster and wear longer.

I've been using Slime for over 25 years on all of my bikes and I swear by the stuff, although it has quirks*. It doesn't do well with punctures caused by spoke heads. You must make sure your rim's spoke heads are covered well. My method is to put 2 wraps of PVC tape over the center rim strip and then put the rim strip over that. Rim strips can move when inflating thick tubes in normal-sized tires. Tire liners can be troublesome with thick tubes as well, and I have seen tire liners cause flats themselves.

And finally, making your tires as heavy-duty as possible usually just makes them heavy. Nothing slows down your bike quicker than heavy wheels and tires.

* Slime quirks
It doesn't work well on patched tubes. It will cause the patches to separate from the tube. Do not patch.
If you get puncture(s), refill tire and keep that wheel spinning. Air up again and keep it spinning as needed.
Never inflate tires with the valve stem at a lower position. Air up tire with valve stem at between 10 and 2 o'clock.
A Slime'd tube may lose it's puncture seal(s) in direct, hot sun. Slime also does not like temperatures below 20F.
You may find that your bike is a bit slower to accelerate and slower uphill with Slime.

Lightweight alternative:
Michelin Protek Max tubes + Kevlar tire or Kevlar tire liner
I just took my tire off and it was a tear caused by a pinch. The slime was just oozing out of there and I'm just glad it held up until I got home as I'm still sore from walking that long distance 2 days ago. I just ordered some kevlar tires and kevlar tire liner. I hope it helps but for the time being I filled up the new tube with slime and aired it up to 60 psi for the rear and 55 psi for the front. It does not flatten at the bottom when I sit on it no where near as much as it did at 40. I'll let you all know how the ride goes to and from work tomorrow as it is a distance of 10 miles one way.
 

BIG BOBBY

Active Member
Joined
Mar 22, 2019
Messages
107
pinch flats happen because you bottomed out. period. either put more air in your tire, or just purchase at tire that will handle a LOT more pressure,..Schwalbe tires have never, ever disappointed me. Schwalbe + slime. just inflate to your heart's content and go. even with Walmart rims. I ALWAYS am thorough when I inspect/service my rims. 3,4,even 5 layers of electric tape for a "rim strip",.. talcum powder, and I put my HAND inside the tire and fish for sharp pokes. take the extra time. cheap tires sometimes have defects. even schwalbes can have defects. you HAVE to manually check. every time. it's your precious life that's at stake.
 

inspectorcritic

Active Member
Joined
Dec 13, 2015
Messages
910
If you run 1.95 I would say buy solid no air no flat tire. You probably have a thorn in your tire run your fingers through the the tire remove it.
 
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