Tire size question

[bikebum1975]

Hey Guys
Got a question on tire size. I have a pair of mountain bike rims that currently have 26X1.95 knobbies on them and I am wondering what is the minimum tire size the rims will take. Reason is I have a panasonic road bike that I want to put a little bit wider tire on it that the 27s that are on there right now. I am also going to be changing it to a Sturmey Archer 8 speed coaster hub and putting a Sturmey drum brake/dyno hub on the front. I would like to turn it into a sort of a trail type road bike in a way. Thanks for the help.
Jim

 

[deorman]

Sprucemoose found some 1.25 somewhere, but decided he didn't like them. I'm running some 1.5 on my build-off bike, they're not bad, but I wouldn't use them off-road. viewtopic.php?f=21&t=14956&st=0&sk=t&sd=a&start=15
viewtopic.php?f=31&t=15894

 

[NLCTVWguy]

There should be plenty of tire options, street tread or more aggressive, that will fit. A LBS might give you a good idea, or try Niagara Cycle (http://www.niagaracycle.com) for a wide selection.

Keep in mind that even tires with the same paper specs are not equal- tires seem to be all over the place in terms of stated width and actual mounted width.

They'll all technically fit the 1.95 rims, or 1.75 rims or 2.125 rims, and I wouldn't expect a lot of trouble fitting the narrowest 26" tire they make on there. That does NOT mean S5/S6 size 1-3/8" tires or any other lightweight tire, just ones for the mountain bike/cruiser size rims.

I have the original rims on my Trek 820 and they're VERY narrow aluminum rims, I'd say they're not over an inch wide, but have 2.125 tires on them and work just fine. The smaller sizes would be more suitable for what you're trying to do.

The tires are a MAJOR change in rim diameter from what you have now, and that would normally cause all sorts of hassle with the brakes- but you are using a coaster rear / drum front setup, so you negate that issue. The problem would be trying to get calipers to reach or cantilever brakes to align properly, and that would be difficult or impossible.

One thing some folks have successfully done, to create a bike like you describe (including Rat Rod himself, if I remember right) is to change out wheels of this size for 700c rims. This allows you to take advantage of a wide variety of "cyclocross" tires that are pretty much in line with your stated mission here it sounds like. Something to consider if the MTB rims don't work out.

Good luck with it, test fit that tire / rim combo and I think you'll find it fits without much problem at all. You can always take the bare frame down to the bike shop and try a couple styles, see how they'll fit on there, if you don't have an appropriate tire readily available.

--Rob

 

[deorman]

700 rims will definitely fit a 27" bike with little or no modification, with a greater variety of tire size and type made, as well as slightly greater clearance for them. Finding lbs that carries larger ones can be hit or miss depending on where you live.

 

[FunkyStickman]

700 rims will definitely fit a 27" bike with little or no modification, with a greater variety of tire size and type made, as well as slightly greater clearance for them. Finding lbs that carries larger ones can be hit or miss depending on where you live.

This is good info, and just so you know, the "new 29-er" MTB tires are actually 700C size. So there's even more tires to choose from if you go that route.

 

[bikebum1975]

700 rims will definitely fit a 27" bike with little or no modification, with a greater variety of tire size and type made, as well as slightly greater clearance for them. Finding lbs that carries larger ones can be hit or miss depending on where you live.

Hey Man thanks for the info I didn't even think of the 700c option.

 

[socal_jack]

A cyclocross tire would likely max out a panasonic road bike, doubt a 29er mtb tire would fit, you'd need some serious clearance for that. Even most 29er mtbs won't take a really wide tire 2.2-2.35 seems to be about it.