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Discussion Starter · #1 · (Edited)
I bought a Motobecane Outcast 29er as a commuter, thinking I could run 700x23 tires, but it has 21 mm rims (Alex, TN21).

Sheldon Brown has a table that says I shouldn't go smaller than 700x35, but tires of that size are hard to come by and pricey here (Korea). Could I go narrower?

Just want to add that I'm a fan of the outcast. Bought it as a commuter, but took it to the hills and it's great :)
 

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Ksyrium were 21mm at some point I think, so 23's will be OK too. Just a PITA to actualy have on a contraption that is used for cycling purpose in the outdoors.

The question I would be asking is what the maximum width would be with there. My own answer would be : for commuting/touring like use, any tire will work, even 60mm.
 

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Alex doesn't list a TD21 here, but they do have a TN21 - and this rim is 21mm bead-to-bead. Ksyriums were maybe 21mm outside-to-outside and the bead on that rim would be about 16mm... 21mm is pretty wide to try to run a 25mm tire. The tire may not grip the bead as firmly as it should to hold high pressure - and a 23 or 25 needs fairly high pressure - at least 90 to 100 psi and really should have a little more if the roads aren't super-smooth. I think 28mm is about as narrow as I would go with that rim, and would suggest that you try to get at least a 32. It'll still roll fine and give you a touch more resistance to bumps, etc... Remember - at 100 psi that tire will have the same contact patch as a narrower tire at 100 psi - it might be a little shorter and wider patch but the area will be the same. If the tire has a light casing and good quality, rolling resistance difference is virtually nothing. Wider tires have more wind resistance at higher speed, but it sound like you are commuting, so speeds are probably 30km/hr or so max anyway, right?
 

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Discussion Starter · #5 ·
Thanks ATBScott, you are right. It's TN 21, and it's 21mm bead to bead. So, wide. You advice sounds good too. It may be possible to find a cheap 28 here, just to try. That seems to be the outside size for regular road racing bikes

Otherwise, I will have to go properly wide but, as I said, they are expensive and not easy to find here.

Apart from the bike path my commute has lots of rough roads. Perhaps Schwalbe Big Apples are the best choice. One of the unicycle shops lists them I think.

Thanks all for your help
 

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Schwalbe has the steel beaded Stelvio 28. I want that to race crits. For commuting, I am hting the 28's and 23's on my road bike, but it's the only bike I have that works (well, broken derailer cable now, gear set stuck in 48x14 now.
 

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Cloxxki - you can't replace a derailluer cable on your bike!?!?!? Or are you trying out the road in a SS mode? It's a 3 to 5 minute fix!
 

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Velocity VXC's are about 16 to 17mm at the bead, not much more than a wide road rim. They are 23.5mm wide at the widest part of the rim, but they narrow back and then the bead flange takes away another few mm...
 

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Discussion Starter · #10 ·
Solved the problem with some 700c x 35 Kenda Kwests. Just cheapo, about $15 each.

They roll so much better than the stock nevegals :)

My Outcast is now the best handling bike I have ever ridden. I can't believe how well it turns in
 

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ATBScott said:
Cloxxki - you can't replace a derailluer cable on your bike!?!?!? Or are you trying out the road in a SS mode? It's a 3 to 5 minute fix!
LOL
I misplaced the lock key to my citybike (I had it to lock it up last night across the street, I didn't have it on my opened keyring this morning), so it was the road bike for today's commute. I had already tied the broken cable to the frame, derailer fixed on the 14t cog. So, 48x14t it is.
I know a thing or two about bike maintenance, but that doesn't mean I give a @$^!$# about spending either time or money of it.
 
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