Inner Tube

[ddebonis]

Simple question: for my 100/90-18 front tire, does a 4.1-18 tube work? Or do I keep searching for a 100mm tube?

[Barry]

I'd say the tube is a better match for a 110 or 120 size tire and therefore might be too big for yours. Basically you don't want it so big that it creases.

Tubes seem to be mostly inch sizes. I would look for a 3.50 tube

[ddebonis]

Thanks!

Here's a stupid question. Why is the tube creasing bad?

[ddebonis]

Luckily I was able to procure a 100/100 - 18. I suspect that's the closest I'm gonna get.

[montmil]

A creased tube, ie: one folded over on itself, will generate friction and eventually a tube failure. Sorta similar to a poorly installed tube being pinched by the rim. Same results, just different ways to get there.

A little baby powder dusted inside the tire and on the tube smoothes the install.

[Luca]

Luckily I was able to procure a 100/100 - 18. I suspect that's the closest I'm gonna get.

Tubes usually have a range, so you don't need a tube that exactly matches your tire.  On my LS I used the same tube both front and rear.

Here's a stupid question. Why is the tube creasing bad?

Creased tubes are prone to tearing.  Tubes can move around a bit on the rim during operation (which is why some poeple say to never keep the valve stem nut tightened down to the rim), and if you have a crease the tube will wear on itself.

[Luca]

Yo Monte, your post has brought up a question I've had about mounting tires with tubes.

When I mounted my tires I powdered the tube and then lubed the tires like everyone else, and it worked just fine.  I've since wondered, however, if the tire lube was just going to make the baby powder cake up?  Any insight from your deep well of wisdom?

[montmil]

Luca, I'm one of those peeps that rides my R65s "out on the edge." As in tubeless. Have done so for the years I've owned these bikes. No talc needed. I would think that a light rub of talc plus the use of lube would not generate nasty clumping.

My '78 R100S -the one with the twin floating caliper ATE brakes, spoked wheels and aluminum Akront rims- runs inner tubes. A also paid a shop to mount new Spifires but I did not watch their procedures.

I find that the different size specifications on so many inner tube offerings can be overpowering; what with the x-references, metrics and such. For the R100S, I provided tire and rim specs to the tire vendor and had them supply me with the correct tubes and rim strips.

I buy all my tires and related supplies from American Motorcycle Tire.

http://www.americanmototire.com/catalog/index.php