Mountain Bike Reviews Forum banner
1 - 20 of 20 Posts

·
Registered
Joined
·
401 Posts
Discussion Starter · #1 ·
Ok so I had nothing better to do over the weekend and decided to try an experiment. I have read for years about people using 26" tubes in the 29" wheel with mixed success. I just got a set of RR (the new tubeless version) and was getting ready to set them via Ghetto. I found a set of Performance Lunar Lite 26 tubes in the cabinet and my curiosity got the best of me so I aired them up outside the tire to expand them a little then mounted the tire with the tubes and took them up to 35psi. Headed out to the trail to see how quick they would either pinch flat or just out right burst

To my surprise I put an hour in and nothing happened! So I dropped the pressure down to 30psi and thought this would surely be the end the experiment so I stayed close to the truck. Again no problem so I set the psi down to 28 (what I normally ride tubeless) and they worked fine.

My point to this rant is although I have run totally tubeless for the past 4 years it has always been a major PITA. The tubes come in at 92 grams on the scale and that is still 26 grams less than my standard tubless setup.

I'm far from sold on this concept but I am going to keep riding this setup just to see what the limitations are.
 

·
Registered
Joined
·
38 Posts
I tried the same thing this weekend. No luck. I used a 26x1.5-2.2 in lieu of 29x1.9-2.3. The tire is a Kenda SmallBlock 2.1. The partially inflated tube would go in the rim but only about half of it was visible above the rim line. Then the beaded tire sidewalls wouldnt seat without difficultly. The tube in the rim was snug and the beads wouldnt slide in between the tube and rim. When I got that problem solved I started inflating the tube. I dont know how much pressure it didnt seem like over 10 psi before the tube ruptured. At that point the tire was still krinkled from underinflation. I had the opposite problem of getting the tire off with the tire levers. I couldnt grab the beaded edge of the tire without grabbing the tube because it was in the way even when completely deflated. The tube was ruptured in more than one place. It could be from using the levers but I think the tube distorting in the rim. The tube was Specialized thin wall. Maybe I would have better luck with normal or thick tubes. Ill stay with repairing the 29 tubes.
 

·
turtles make me hot
Joined
·
11,663 Posts
My front tire somehow tried to escape from my rim once during a ride and the tube exploded and was unrepairable. Somehow, I left my seatbag with the spare tube in my truck. I started walking back when another rider offered up a 26" tube. It's been in there since last September. No problems whatsoever.
 

·
ballbuster
Joined
·
12,718 Posts
I run 26" Lunar Lites in all my 29er bikes. Never an issue. I flat about once or twice a year... which is about how often I flatted on my 26er bike.

I ride in places with pointy rocks, but not thorns so much, and I run 26/28 psi pressure on 29x2.1-2.3 tires.... give or take a bit for conditions.

Basically, any object that can poke through the tire carcass is going to flat any innertube regardless... with the exception of Slime tubes.

Basically, the innertube is not structural in any way shape or form.... as long as you aren't stretching it beyond the butyl's limits. 26er tubes for instance don't have to stretch much to make it around a 29er wheel, but a 700c road tube would have to stretch a lotta lot.

You have come to the same conclusion I have about tubeless. In the two or three times I tried it, it was a major PITA. Then again, I didn't have full blown tubeless tires. I ran Bontrager tubeless rim strips in my Mustang rims, with Bontrager valve stems and Stan's sealant. Maybe not the best combo for success. With all of this hassle, there is no weight advantage over a Lunar Lite tube, and those go in easy. If I rode in thorny areas, I would probably me more motivated to go tubeless.
 

·
Registered
Joined
·
401 Posts
Discussion Starter · #7 ·
SpaceCowboy853 said:
I tried the same thing this weekend. No luck. I used a 26x1.5-2.2 in lieu of 29x1.9-2.3. The tire is a Kenda SmallBlock 2.1. The partially inflated tube would go in the rim but only about half of it was visible above the rim line. Then the beaded tire sidewalls wouldnt seat without difficultly. The tube in the rim was snug and the beads wouldnt slide in between the tube and rim. When I got that problem solved I started inflating the tube. I dont know how much pressure it didnt seem like over 10 psi before the tube ruptured. At that point the tire was still krinkled from underinflation. I had the opposite problem of getting the tire off with the tire levers. I couldnt grab the beaded edge of the tire without grabbing the tube because it was in the way even when completely deflated. The tube was ruptured in more than one place. It could be from using the levers but I think the tube distorting in the rim. The tube was Specialized thin wall. Maybe I would have better luck with normal or thick tubes. Ill stay with repairing the 29 tubes.
I think you may have had a bad tube. I found an older Lunar Lite last night that needed patched. I fixed the tube and started pumping it up with a floor pump. It expanded about 5' in diameter but did not fail. The tubes I used in the 9er were 1.95-2.25 but I really don't think the next size down would make that much of a difference.
 

·
Registered
Joined
·
401 Posts
Discussion Starter · #8 ·
pimpbot said:
I run 26" Lunar Lites in all my 29er bikes. Never an issue. I flat about once or twice a year... which is about how often I flatted on my 26er bike.

I ride in places with pointy rocks, but not thorns so much, and I run 26/28 psi pressure on 29x2.1-2.3 tires.... give or take a bit for conditions.

Basically, any object that can poke through the tire carcass is going to flat any innertube regardless... with the exception of Slime tubes.

Basically, the innertube is not structural in any way shape or form.... as long as you aren't stretching it beyond the butyl's limits. 26er tubes for instance don't have to stretch much to make it around a 29er wheel, but a 700c road tube would have to stretch a lotta lot.

You have come to the same conclusion I have about tubeless. In the two or three times I tried it, it was a major PITA. Then again, I didn't have full blown tubeless tires. I ran Bontrager tubeless rim strips in my Mustang rims, with Bontrager valve stems and Stan's sealant. Maybe not the best combo for success. With all of this hassle, there is no weight advantage over a Lunar Lite tube, and those go in easy. If I rode in thorny areas, I would probably me more motivated to go tubeless.
Thanks for the +1 Pimpbot. When I originally posted I thought for sure I was opening the flood gates for a major [email protected]# chewing from the tubeless Nazi's.Don't get me wrong, I still think as more and more manufactures come out with tubeless ready tires and rims I will eventually end up there for good but for now if I can find an easier alternative I'm going to jump on it.
I have ran strips, Ghetto via the cut tube method and most recently Ghetto with Gorilla tape. To date the Ghetto-Gorilla tape method has worked the best. I have managed to make them all work one way or the other but the one constant was it was always a major pain and when flying down a stretch of single track the thought of that front tire coming off the rim (never happened) was always in the back of my mind
 

·
Registered
Joined
·
401 Posts
Discussion Starter · #9 ·
Now I'm really curious. Who else is running 26" tubes in the 29" wheels and what pros or cons have you ran into.

And please I don't need a 20 post dissertation on the virtues of going tubeless as I am well aware of the benefits
 

·
Registered
Joined
·
914 Posts
SpaceCowboy853 said:
I tried the same thing this weekend. No luck. I used a 26x1.5-2.2 in lieu of 29x1.9-2.3. The tire is a Kenda SmallBlock 2.1. The partially inflated tube would go in the rim but only about half of it was visible above the rim line. Then the beaded tire sidewalls wouldnt seat without difficultly. The tube in the rim was snug and the beads wouldnt slide in between the tube and rim. When I got that problem solved I started inflating the tube. I dont know how much pressure it didnt seem like over 10 psi before the tube ruptured. At that point the tire was still krinkled from underinflation. I had the opposite problem of getting the tire off with the tire levers. I couldnt grab the beaded edge of the tire without grabbing the tube because it was in the way even when completely deflated. The tube was ruptured in more than one place. It could be from using the levers but I think the tube distorting in the rim. The tube was Specialized thin wall. Maybe I would have better luck with normal or thick tubes. Ill stay with repairing the 29 tubes.
sounds like either you pinched it with the levers or maybe you still had a thorn stuck in your tire. My friend did that and on the third tube he was changing I asked him if he checked the tire for thorns and sure enough we found 2. It doesn't make too much sense to me that a smaller tube on a bigger wheel would result in multiple holes. I have run 26" tubes in 29'er wheels on the trail to get back to the car and they are harder to put on so you don't pinch the tube. I didn't use a tire lever and made sure the tube was clear of the bead before pumping up.
 

·
Map Maker
Joined
·
1,244 Posts
I've run Maxxis Ultralight 26" tubes for about a year in my 29er tires with no troubles - I've got 26" bikes and 29" bikes and was just too lazy and cheap to buy a second set of tubes.

Worked great. I eventually bought a set of 29er Kenda tubes and put them in - they are about 100 grams heavier per wheel. I did it because the Maxxis tubes got so expensive I couldn't get them for cheap anymore.
 

·
Registered
Joined
·
38 Posts
pamt said:
I think you may have had a bad tube. I found an older Lunar Lite last night that needed patched. I fixed the tube and started pumping it up with a floor pump. It expanded about 5' in diameter but did not fail. The tubes I used in the 9er were 1.95-2.25 but I really don't think the next size down would make that much of a difference.
If there is a next time Ill use a larger 26 tube. This was brand new. I still will have a problem seating the tire folding bead. I can get the tire on without damaging the tube. But getting it off with tire irons will still be a problem as I stated before. The guy at the LBS just uses his hands to roll the bead on and off. I can roll the bead on but my hands arent strong enough to roll it off. Im constantly patching tubes from thorns. Im using WTB LaserDisc rims. I wonder if there is something in the channel causing a problem with the 26 tube. The spoke strip is intact. Ive overinflated tubes finding small leaks. The outside diameter changes but the inner doesnt. The LBS throws away 26 MTB tubes everyday. Every once in awhile a 29er. If the 26 tubes work Id never have to pay for tubes again except my time patching. Id only have to carry one tube for my 26 and 29. I was in a group ride yesterday where a 100psi road tire blew like a truck tire.
 

·
rider
Joined
·
808 Posts
I've run plenty of 26" tubes in 29 tires and in my opinion they're only a hair more challenging to install, lighter and don't seem any more prone to flats. I like to blow them up before installation and get some pre-stretch. I often carry a 29" tube for trail repairs just for ease of repair. Conti makes a 26" tube with removable valve core if you'd to add your sealant of choice for additional flat protection.
 

·
Registered
Joined
·
38 Posts
brent878 said:
sounds like either you pinched it with the levers or maybe you still had a thorn stuck in your tire. My friend did that and on the third tube he was changing I asked him if he checked the tire for thorns and sure enough we found 2. It doesn't make too much sense to me that a smaller tube on a bigger wheel would result in multiple holes. I have run 26" tubes in 29'er wheels on the trail to get back to the car and they are harder to put on so you don't pinch the tube. I didn't use a tire lever and made sure the tube was clear of the bead before pumping up.
I think you are probably right. I change enough tubes not too look for thorns. I remember using the tire levers to set the bead. I must have pinched. I normally dont use levers to seat a tire. As I just stated in another post my hands arent strong enough to unseat the tire. I use levers. Ill give it another shot the next time. I can get some free 26 MTB tubes from my LBS if I patch them.
 

·
Banned
Joined
·
2,320 Posts
Have run 26" tubes in my 29ers for 5 yrs w/o issue. Done initially to make trail repairs easier, as most friends were using 26" bikes. Now, I only carry 26" tubes, and have found that the 26 x 2.0-2.3 works well. Now living in blackberry-ville, I got thorned more last year than ever, and am being tempted to go to the dark side of goo.
 

·
Registered
Joined
·
914 Posts
SpaceCowboy853 said:
I think you are probably right. I change enough tubes not too look for thorns. I remember using the tire levers to set the bead. I must have pinched. I normally dont use levers to seat a tire. As I just stated in another post my hands arent strong enough to unseat the tire. I use levers. Ill give it another shot the next time. I can get some free 26 MTB tubes from my LBS if I patch them.
I usually don't use tire irons and just use my hands like your LBS. But with a new tire sometimes its pretty tight and I have to use tire irons for the last part. But I also use plastic tire irons and try to be super carefull not to get the tube cought. I guess its from changing so many motorcycle tires. If you pinch the tube in a motorcycle tire you get to start all over again and its such a pain in the butt to do that you try your hardest not to pinch them.

The reason I was pointing it out was becuase I didn't want you to think the 26" tube was the cause for the holes and give up on them. If you get them free its even better. But I do think that a 26" tube in a 29" tire makes it easier to get them cought in the bead so just be extra careful when your putting them on.
 

·
Registered
Joined
·
643 Posts
I started using 26er tubes on my very first 29er because at that time they were very hard to find (29er tubes). Really, it makes no diff.

As far as tubless... if you live in an area with thorns all over, then yea... might be worth it. Otherwise, I don't see the point.
 

·
saddlemeat
Joined
·
3,873 Posts
Tessaiga said:
So does that mean that a 26" 2.5 - 3.0 DH inner tube would work very well for 29er purposes??
No, because the width of the tire is the same for 29 tires, they just have to get a little longer, but it's comparatively less stretch than the difference between 1.95 amd 2.25 in width. Do the math, I did it once and it gave me a headache but it did reveal that the stretch from 26 in diameter to 29 in diameter isn't much in relation to the total length of the tube and is well within the design parameters. It may get tt thinner, but no more so than the stretch between 1.95 and 2.25 in width. I think the 26 tubes are easier to install if you blow them up a little by mouth because they snap neatly on and don't want to flop out as I'm rolling the bead on by hand.
 
1 - 20 of 20 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top