Winter Cycling - Will 700x35 and 700x40 tires fit on my 700x38 rims?

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HopliteGrad
10-14-08, 10:34 PM
I'm trying to figure out how to mount schwalbe marathon winters on 38 rims.


cyccommute
10-14-08, 11:39 PM
I'm trying to figure out how to mount schwalbe marathon winters on 38 rims.

Yes. You could probably go to a 28mm on the small side and up to a 47 on the other end. There's lots of wiggle room on tire size. A 32 or 40 would easily work.

I-Like-To-Bike
10-15-08, 10:05 AM
I'm trying to figure out how to mount schwalbe marathon winters on 38 rims.

It is dependent on rim width. From Sheldon Brown site:


HopliteGrad
10-15-08, 12:50 PM
Sweet, I won't have to get additional wheels to pull this off. That's excellent news! Thanks guys!

cyccommute
10-15-08, 02:53 PM
It is dependent on rim width. From Sheldon Brown site:

Those values are very conservative in my opinion. A Mavic XM719 is a 19mm rim and can take a tire from 1.5" to 2.3". Even that is somewhat conservative, certainly on the low end.

HopliteGrad
10-15-08, 05:35 PM
I think I don't fully understand the specification. If 700x38 wheels are not 38 mm wide, what does the 38 represent?

D0ugB
10-15-08, 06:36 PM
The 38 indicates tire width in mm -- the chart that ILTB shows gives you an acceptable range of tire widths that will fit a given rim width -- I believe the origin of that chart is from Mavic originally(not sure looking at it again though)

I-Like-To-Bike
10-15-08, 07:19 PM
The 38 indicates tire width in mm -- the chart that ILTB shows gives you an acceptable range of tire widths that will fit a given rim width -- I believe the origin of that chart is from Mavic originally(not sure looking at it again though)

Source of chart for me was: http://sheldonbrown.com/tire-sizing.html
Sheldon gave credit to: Georg Boeger at http://tandem-fahren.de/Technik/Reifentips/index.html


Those values are very conservative in my opinion. A Mavic XM719 is a 19mm rim and can take a tire from 1.5" to 2.3". Even that is somewhat conservative, certainly on the low end.

You are correct, the chart is conservative, my commuting bike has 19mm rims and it came new with 622mm (700C) x 47mm tires and I've been using that size for over 6.5 years everyday with no problems.

CastIron
10-16-08, 08:45 AM
That chart is beyond "very conservative". Was it designed to sell rims or lawyers?

I-Like-To-Bike
10-16-08, 09:28 AM
That chart is beyond "very conservative". Was it designed to sell rims or lawyers?

I believe it was designed with tandem use in mind. If it was good enough for Sheldon to reprint, it is good enough for me to trust until something better is pointed out by one of our BF buddies.

pinkrobe
10-16-08, 09:32 AM
I had a bad experience using 700x38C Schwalbe Snow Studs on Mavic Open Pro rims [19mm width?]. They mounted fine, inflated fine, handled the test ride around the block just fine. I ride to work and they rolled off the rim about halfway there. I had to keep the inflation pressure down to 20 psi. My new wheelset had 24mm wide rims [some Mavic touring rim], and I haven't had a problem since. My experience is, when in doubt, go with wider rims.

[Side note: HED's new Ardennes road racing wheel has a 23mm profile, but is designed to work with 23C tires. The idea is that the tire will have a less upright profile, thus firming up the sidewalls and making cornering more predictable and reducing rolling resistance.]

gomadtroll
10-16-08, 10:32 PM
Schwalbe has a chart also., less conservative ?

"European Tire and Rim Technical Organization
Standards Manual - 2007

http://www.schwalbetires.com/tech_info/tire_dimensions#rim"

HopliteGrad
10-17-08, 10:27 AM
Haha! Can you imagine the meetings of the European Tire and Rim Technical Organization?

"My God, man, you can't include RFC 83329c in the latest spec! It's madness! Madness I tell you!"

"Get a hold of yourself, Jenkins! Eloise's plan may seem daft but it could just save us all!"

"You don't understand, Witherspoon! The aramid beads just can't take that kind of torsional force. The fibers will shear--you'll have calamity. Blood in the streets! Chaos! Rioting within the week!"

[Jenkins, overwrought, moves to the balcony overlooking the Rhine to have a pipe]