Looking to solve the “latex inner tubes for 650 wheels” problem, but don’t want to blow $200 figuring it out myself via trial n error (tubes are $11/ea.) if possible.
anyone done it? Recommendations? Tips? Procedures?
Thanks in advance.
BQ
I have made 4 of these so far. 3 of them were cut down from 700c, and one was removed from a 650c tubular after a flat. All of them leak significantly faster than I am willing to use for myself or my girlfriend. I’ve gone back to Michelin airstop comp for her HED Jet 90/60 set, which are very thin butyl. All of my race wheels are tubular, so I have latex tubes in them already.
Chris
I think I remember reading that psycholist has done this. Try sending a PM to him.
I’ve done it! Worked like a charm … sort of. I glued 'em up about 6 weeks ago (cut down 700c Vredestein tubes). Mounted them up in my race wheels in anticipation of the Tundra Time Trial (Atlanta) on 2/14. Put about 100 miles on them in pre-race just to be sure they were going to hold up, plus I did a couple of preview rides on the course the day before the race. All went quite well. So on race morning, I pull the bike out of my truck (I had to travel to Atlanta) and the rear disc was flat. AAAaaaaarrrrgh! I hurriedly installed a butyl spare I had and raced that. The front was still golden and was excellent in the race (which had three significant breaks in the pavement that would challenge any tire/tube). The rear, as it turns out, did NOT fail at the glue junction where I’d put it together. Something got into the tread in the wet conditions and came through the tire to puncture the tube. So it would have happened to a butyl tube just the same.
First, make sure you have RUBBER cement, not contact cement. I tried contact cement first and it didn’t work at all. Vredestein or Vittoria tubes are better to work with because they don’t have all the powder on them that Michelin tubes have. Plus, The V brand tubes have removeable cores which I like because you can use the good kind of valve extenders.
I blow a little air into the tube by mouth to give it shape, then I lay it around the rim track of my 650c wheel. I pinch the base of the excess opposite the valve and cut the tube to give me about 2 extra inches beyond what would make the ends meet.
I have an old aero extension with smooth ends on it. You can use something like that, or just a smooth broom handle. I sit on a stool with the aero extension pointing up between my knees. I hold one of the cut ends of the tube alongside the extension with 2 inches extending beyond the end of the aerobar. I stick my fingers into the end of the latex tube and open it up wide, folding those two inches back over the end of the aerobar so I end up with the tube running along one side of the aerobar to the end which is folded back on itself (over and surrounding the aerobar) by two inches. Two inches of the inside of the tube are now turned outward at the end of the aerobar. I apply the rubber cement liberally and evenly to these two inches. While the glue is still wet, I put my finger in the other cut end of the tube and open it as wide as I can. Then I carefully slide this over the section where I just applied glue … until the cut ends meet up. Then I get my fingers out and, it’s time to let things dry. I let it dry overnight. In the morning, I peel the tube off of the aero extension and, voila! It ain’t purdy … but it works! Blow a little air in to give it shape, mount it up, air it up and give it a test ride. It looks like there’d be a big bump in the tire where you glued those ends together, but you’ll never notice anything.
I need to glue up another one for that rear wheel and, when I do, I plan to take some pictures. A picture is worth 1,000 words. Sorry for the thousand words.
Bob
What about not cutting the tube and just pushing a section inside itself. Maybe add some glue to keep it together. That section would be three times the thickness, but no cutting involved and much faster to make.
Styrrell
Can’t see why it wouldn’t work, but I’m not sure it’ll be easier. I can’t see you having a very easy time handling the tube for gluing and folding it back on itself, but I haven’t thought about it much. The way I described really isn’t that hard. It’s just hard to describe.
thanks Bob,
Would love to see pics, but your 1000 words should be enough. I’ll let you know how it goes.
This is all very interesting. Next question:
Would a 21-23 mph rider such as myself notice a difference between butyl and latex tubes??? Seems hard to believe. I mean, I get that they’re more supple, and often lighter than butyl, but compared to the tire they’re crushed up against, seems like the tube would be practically insignificant.
???
You can decide for yourself how important a few watts are to you. Here’s some data from Al Morrison’s Crr compilation (Revision 8):
Vittoria Open Corsa EVO CX 700x23 with butyl tube crr = .00307 15.1 watts per wheel
Vittoria Open Corsa EVO CX 700x23 with latex tube crr = .00261 12.8 watts per wheel
Vittoria Open Corsa EVO CX 700x23 with butyl tube crr = .00307 15.1 watts per wheel
Vittoria Open Corsa EVO CX 700x23 with latex tube crr = .00261 12.8 watts per wheel
Wow, bigger difference than I would have thought. Thanks.