Advice for mounting tires without "blowing" tube
#1
Senior Member
Thread Starter
Join Date: Mar 2011
Posts: 137
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Advice for mounting tires without "blowing" tube
FIrst, I know nothing about changing tires on a bicycle, but the captain does. He has done this (both for regular maintanance and on the road after flats) for 20 plus years. When we got our tandem it had Vittoria Rubino Pro 700x28 tires and we had 6 flats in 8 weeks. Changed lots of them. Then we switched to a sturdier Panaracer RIBO 700x28 tire, and still using the Performance 28-32 tubes and it seems that 30-45% of the time when he changes a tire and pumps it up again the tube blows. He has used the same technique he's used for years but said the bead on the tire must be hard to set. This last time he put 2 new tubes and two existing tires with 1000 miles on and prepared them carefully, going around the rim and hand checking everything and then cautiously pumped them up to only 80 psi and let them sit overnight that way. The next day he finished pumping up to 120psi and one of the two--BOOM-- and a 2-inch split in the tube. This is NOT happening at the valve stem. I, of course, am the nervous stoker who is afraid that someday we will be stuck in the rain along side a road with no shoulder (and uphill both ways and we'll have a flat and when we change it the tube will BOOM again and we'll be stranded if we blow up the 2nd spare tube also. If it's so difficult to keep this from happening in the ideal conditions of our garage, with a floor pump, etc. why should changing a tire on the road be any better? Has this happened to any of you, and if so how did you prevent it or how could you even identify that something was amiss and the tube was going to blow? This has happened on the same tires and tubes on two completely different wheelsets, so it's not the wheels.
#2
Galveston County Texas
Join Date: Nov 2007
Location: In The Wind
Posts: 33,221
Bikes: 02 GTO, 2011 Magnum
Mentioned: 18 Post(s)
Tagged: 0 Thread(s)
Quoted: 1346 Post(s)
Liked 1,236 Times
in
617 Posts
It happens to everyone when the tube is pinch between the tire bead and wheel rim.
I put the tube inside the tire, add a little air before putting the tire (with the tube inside) on the wheel.
Air up to 30-40 lbs then let all the air out.
Then Air up to the desired psi.
I put the tube inside the tire, add a little air before putting the tire (with the tube inside) on the wheel.
Air up to 30-40 lbs then let all the air out.
Then Air up to the desired psi.
__________________
Fred "The Real Fred"
Fred "The Real Fred"
#3
Senior Member
Join Date: Sep 2007
Location: Machias, WA
Posts: 718
Bikes: Rodriguez Toucan tandem, Rodriguez Rainer Lite sport/touring
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Check that the rim tape is completely covering the spoke holes. Also, applying talcum powder can help prevent the tube from sticking to the tire while mounting.
#4
hors category
Join Date: Jan 2002
Posts: 7,231
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 8 Post(s)
Likes: 0
Liked 5 Times
in
5 Posts
There are a lot of different reasons that certain tires can make mounting a challenge and/or invite blow-offs & pinch flats.
My first question would be, how hard is it to mount the tires on the two different rims y'all have used? Just given how meaty the RimBO tires are I would expect them to be a tight fit. If they're not, then there may in fact be a bead seating issue where the tire and your rims just aren't well matched. It happens every now and again.
If one of the rims that you're having trouble with using these tires is a daVinci V-23 you might want to give Todd or Brian a call at daVinci to find out if they know about any rim incompatiblity issues with the RimBO tires and their rims. Same thing goes for the other rim. If you bought it from a tandem speciality dealer consider giving them a call to see if they're aware of any incompatibility issues. Years ago there was a rash of tire compatibility issues between certain Panaracer tires and rims. I don't recall which ones off hand, but it was just one of those things where both the bead seat design and size of the tire didn't play well with certain rims.
I only mention this because it does sound like your captain is doing everything right: got nothing else to offer there. If that's the case, and the tires are only blowing once they're pumped up to 120 psi I suspect the tire bead is coming unseated and allowing the tube to essentially ulcerate as it tries to escape through the gap. This is a little bit different than a traditional pinched tube that was accidentally caught between the rim and tire bead during mounting.
Now, if the tire fits well, then there may still be a bead seating issue. Again, your captain is on the right track with doing a partial inflation and then doing a check as described but with most of the emphasis on making sure the bead is seated evenly all the way around the tire. If the bead tape edge seems to be high or low in any one spot, release a little air and then work to get a uniform and parallel line between the rim and the bead tape all around both sides of the tire. The newer Vredestein's that we're now using seem to demonstrate this same unwillingness to seat evenly by themselves and take an extra bit of attention when mounting. Of course, that's only when they're new... so I'm more inclined to think it's something else (see above) if you had a blow-off on tires that had 1,000 miles of use following a remounting.
My first question would be, how hard is it to mount the tires on the two different rims y'all have used? Just given how meaty the RimBO tires are I would expect them to be a tight fit. If they're not, then there may in fact be a bead seating issue where the tire and your rims just aren't well matched. It happens every now and again.
If one of the rims that you're having trouble with using these tires is a daVinci V-23 you might want to give Todd or Brian a call at daVinci to find out if they know about any rim incompatiblity issues with the RimBO tires and their rims. Same thing goes for the other rim. If you bought it from a tandem speciality dealer consider giving them a call to see if they're aware of any incompatibility issues. Years ago there was a rash of tire compatibility issues between certain Panaracer tires and rims. I don't recall which ones off hand, but it was just one of those things where both the bead seat design and size of the tire didn't play well with certain rims.
I only mention this because it does sound like your captain is doing everything right: got nothing else to offer there. If that's the case, and the tires are only blowing once they're pumped up to 120 psi I suspect the tire bead is coming unseated and allowing the tube to essentially ulcerate as it tries to escape through the gap. This is a little bit different than a traditional pinched tube that was accidentally caught between the rim and tire bead during mounting.
Now, if the tire fits well, then there may still be a bead seating issue. Again, your captain is on the right track with doing a partial inflation and then doing a check as described but with most of the emphasis on making sure the bead is seated evenly all the way around the tire. If the bead tape edge seems to be high or low in any one spot, release a little air and then work to get a uniform and parallel line between the rim and the bead tape all around both sides of the tire. The newer Vredestein's that we're now using seem to demonstrate this same unwillingness to seat evenly by themselves and take an extra bit of attention when mounting. Of course, that's only when they're new... so I'm more inclined to think it's something else (see above) if you had a blow-off on tires that had 1,000 miles of use following a remounting.
Last edited by TandemGeek; 03-26-12 at 10:58 AM.
#5
Senior Member
Thread Starter
Join Date: Mar 2011
Posts: 137
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Thanks Tandem Geek. da Vinci puts the Ribmo on just about all of their V23 rims for bikes that they sell, unless the customer wants a different tire, so no compatibility there or they wouldn't be using it themselves. Will look more closely at your other suggestions too. It's not really that frustrating, unless it happens when were not home (that hasn't happened yet but you know Murphy's law--if it does it will be in the worst possible place without cell phone coverage).
Thanks everyone, we'll keep looking and trying.
Thanks everyone, we'll keep looking and trying.
#6
Senior Member
Join Date: Jan 2008
Location: Ft Worth, TX
Posts: 1,971
Bikes: Custom 650B tandem by Bob Brown, 650B tandem converted from Santana Arriva, Santana Noventa, Boulder Bicycle 700C, Gunnar Sport
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 23 Post(s)
Likes: 0
Liked 4 Times
in
4 Posts
This is a tough one. One more thing to try is another batch / brand of tubes. Inexpensive tubes have been known to have defective batches.
#7
just another gosling
Join Date: Feb 2007
Location: Everett, WA
Posts: 19,501
Bikes: CoMo Speedster 2003, Trek 5200, CAAD 9, Fred 2004
Mentioned: 115 Post(s)
Tagged: 0 Thread(s)
Quoted: 3873 Post(s)
Liked 1,920 Times
in
1,369 Posts
I'll reinforce TG's idea to look at the rim tape very closely. It could be the Ribmo tires have something different about the bead (maybe larger?) and your rim tape isn't giving the bead room to seat behind the rim's hook. It has seemed to me that no matter how tight or loose the tire seems on the rim, the bead will hold as long as the rim tape or a bit of tube isn't in the way. The tubes you are using are quite heavy and very unlikely to get caught in the bead, plus I'm sure your captain is checking closely. You could try a slightly narrower tape.
However, another thing you could try is using a smaller tube. Those are huge tubes you're using. A Performance 19-26 tube will work fine in a 28c tire. See what that does. Of course pump it 'til it's round before installing.
However, another thing you could try is using a smaller tube. Those are huge tubes you're using. A Performance 19-26 tube will work fine in a 28c tire. See what that does. Of course pump it 'til it's round before installing.
#8
Senior Member
Join Date: Jul 2008
Location: Pittsburgh
Posts: 270
Bikes: '06 Titus mtb, 2004 Trek T2000 tandem, '88 Merckx 753, '18 Emonda, '91 Cannondale mtb, '19 Trance 29er
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
I'd agree to try getting tubes that are the correct size. I wouldn't even go undersized. It's a bit difficult sometimes, but you can find tubes that span the 700x28 size.
(I've had an undersized mtb tube blow out when I wasn't even riding the bike. I had previously installed a bigger tire and figured rubber can stretch. Rode about an hour without a problem. Then, sitting on the ground beside the bike for 10 minutes or so, I heard BOOM. The tube had split right along a seam that was there from the mfg process. Actually, I didn't think those were seams, but thought they were just flashing from the mold design, but whatever those ridges are, maybe they can't stretch as much as a pure sheet of rubber. I didn't find any thorn or exposed spoke, so I just put in a correct-sized tube and haven't had the problem again.) (I guess it also could've been an unlucky mfg defect and just a coincidence that the tube was smaller than suggested.)
(I've had an undersized mtb tube blow out when I wasn't even riding the bike. I had previously installed a bigger tire and figured rubber can stretch. Rode about an hour without a problem. Then, sitting on the ground beside the bike for 10 minutes or so, I heard BOOM. The tube had split right along a seam that was there from the mfg process. Actually, I didn't think those were seams, but thought they were just flashing from the mold design, but whatever those ridges are, maybe they can't stretch as much as a pure sheet of rubber. I didn't find any thorn or exposed spoke, so I just put in a correct-sized tube and haven't had the problem again.) (I guess it also could've been an unlucky mfg defect and just a coincidence that the tube was smaller than suggested.)
#9
Senior Member
Once I have the tire mounted I let all of the air out and then visually inspect all around both sides do the tire rim joint to make sure that the tube is inside of the tire and not protruding out of the tire. It is hard to describe but it is very simple to do, you kind of have to pinch the tire as you rotate it to take a close look. I had the same problem and this technique has resolved the issue.
Wayne
Wayne
#10
Senior Member
Join Date: Jul 2009
Location: Central Coast, California
Posts: 3,370
Bikes: Colnago C-50, Calfee Dragonfly Tandem, Specialized Allez Pro, Peugeot Competition Light
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Rim Tape! Make sure it's good quality tape and not that cheap plastic stuff.
#11
Senior Member
Join Date: Dec 2009
Location: Long Island, NY
Posts: 198
Bikes: Serotta Legend Ti, Santa Cruz Heckler, Santana Visa TAndem
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
I'd have to say that, as TG says, there might be a rim/tire bead incompatibility going on. My technique is to put one side of the tire on first, inserting the tube after it has been inflated enough to hold its shape while unsupported. This will tend to keep the slightly inflated tube well away from harms way when you push the remaining bead over the rim and seat it. By all means, push the bead away from the rim to make sure that you don't see trapped tube, but I'm not a fan of pumping up and then deflating the tire. This can undue your precautions when the tube is limp.
I agree with Homeyba...High quality rim tape is important, but it doesn't sound like a factor here. I was haveing small holes develope in my tubes on a set of Mavic Cosmic wheels. It turned out that the extruded plastic Mavic rim tape, which resembled package strapping, was splitting slightly and the tube was getting pinched where the tape was suspended over the spoke holes. A switch to Velox cloth tape solved the issue.
I agree with Homeyba...High quality rim tape is important, but it doesn't sound like a factor here. I was haveing small holes develope in my tubes on a set of Mavic Cosmic wheels. It turned out that the extruded plastic Mavic rim tape, which resembled package strapping, was splitting slightly and the tube was getting pinched where the tape was suspended over the spoke holes. A switch to Velox cloth tape solved the issue.
#12
Senior Member
Join Date: Aug 2011
Location: Seattle
Posts: 201
Bikes: Spec. Roubaix, Cannondale RT2, BF NWT, BF tandem
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
It happens to everyone when the tube is pinch between the tire bead and wheel rim.
I put the tube inside the tire, add a little air before putting the tire (with the tube inside) on the wheel.
Air up to 30-40 lbs then let all the air out.
Then Air up to the desired psi.
I put the tube inside the tire, add a little air before putting the tire (with the tube inside) on the wheel.
Air up to 30-40 lbs then let all the air out.
Then Air up to the desired psi.
Another essential I have found is to coat both the tube and the inside of the tire with talc. This lets the tube move a bit when inflating so it is not bunched up inside the tire. Years ago I blew a tire off the rim while inflating before a ride, but have not had a single problem since adopting this method.
Thread
Thread Starter
Forum
Replies
Last Post
Ron Harry
Bicycle Mechanics
14
08-30-12 06:52 PM