Hi All, I'm replacing my tires. Am using Dunlop K70 front & rear. I'm in USA.
3.25-19 front, 4.00-18 rear.
I'm finding natural rubber tubes are much easier to come by in my size. The question is in practice how much more often will I need to air up tires?
I find my Kenda butyl tubes loose about 1# in 2-3 weeks. These tubes are the thin road bike tubes, not heavy duty or MX,
Bringing bike from storage had original Dunlop tubes from new. Both front & rear were narrower flattened than new tubes now available.
Last 2 times I got Kenda brand tubes front 3.25/3.50-19. About 1/4" wider than originals when flattened.
Kenda rear 3.75/4.00/4.25, again about 1/4" wider when flattened. Kenda says they are made of butyl.
Kendas worked good. However seem no longer made in inch size. Trying to compare to metric, seems metric are yet 1/4" wider again so 1/2" wider than originals. Or the next size smaller is way narrower. I took many tubes from boxes at Cycle Gear trying to figure out a size I liked. They didn't stock my size tubes exactly though.
You go online & many sellers say they have the correct size, but in fact they are the too wide sizes. Many sell 3.25-4.10 as one size fits all when it arrives. Again too wide.
Bikemaster makes tubes in the above inch sizes in natural rubber. These are only 1/8" wider than Kenda & not too thick. They call these Performance tube. Aired up to round out, these tubes seem to fit inside tire fine. Not actually too fat to fit.
Extra thick off road tubes are easy to come by, but I don't want them.
Exactly what brand & model of tube are you guys using for my size K70s?
Thanks, Don
3.25-19 front, 4.00-18 rear.
I'm finding natural rubber tubes are much easier to come by in my size. The question is in practice how much more often will I need to air up tires?
I find my Kenda butyl tubes loose about 1# in 2-3 weeks. These tubes are the thin road bike tubes, not heavy duty or MX,
Bringing bike from storage had original Dunlop tubes from new. Both front & rear were narrower flattened than new tubes now available.
Last 2 times I got Kenda brand tubes front 3.25/3.50-19. About 1/4" wider than originals when flattened.
Kenda rear 3.75/4.00/4.25, again about 1/4" wider when flattened. Kenda says they are made of butyl.
Kendas worked good. However seem no longer made in inch size. Trying to compare to metric, seems metric are yet 1/4" wider again so 1/2" wider than originals. Or the next size smaller is way narrower. I took many tubes from boxes at Cycle Gear trying to figure out a size I liked. They didn't stock my size tubes exactly though.
You go online & many sellers say they have the correct size, but in fact they are the too wide sizes. Many sell 3.25-4.10 as one size fits all when it arrives. Again too wide.
Bikemaster makes tubes in the above inch sizes in natural rubber. These are only 1/8" wider than Kenda & not too thick. They call these Performance tube. Aired up to round out, these tubes seem to fit inside tire fine. Not actually too fat to fit.
Extra thick off road tubes are easy to come by, but I don't want them.
Exactly what brand & model of tube are you guys using for my size K70s?
Thanks, Don
