question on rear tire sizes...?

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Flagg

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i cant seem to find the answer online, if anyone has an answer, or a link to the proper thread, please inform me.

my 81 xs400 rear wheel is 16x2.15 and the current tire on the rim is 120/90/16

all the tires i can mostly find in that size range say that the recommended rim width is 3.00

im confused by this. can i put a tire that the manufacturer recommends as 3.00 on a 2.15?

if so, what is the max size i can shop for?

more specifically, here is the tire i want:
http://www.avonmoto.com/products/cruiser-touring-custom/cobra_ww
MT90B16 *WW rear tire (bottom of the list)

as you can see, they say the minimum rim width is 2.50

help me out bros. next stop for me is actually calling Avon to ask for an answer.

thanks! :bike:
 
It wants a 3 inch rim because it's a 5.2 inch wide tire. Its huge. The manufacturer recommends a rim width, since it directly affects the sidewall geometry and the overall profile of the tire. Some people don't care, and just use whatever for the looks. If you value riding over show bike, get tires that fit. If it's a show bike, then it doesn't matter since it wont get ridden anyway.

You are going to run into chain issues with a 5.2 inch wide tire, so keep that in mind. No way a 530 chain will clear it. I had to rig up quite a bit to get my 520 chain to clear, we're talking the smallest 520 width chain available and a shimmed sprocket that cant be moved any further. Maybe on a smaller rim width you'd end up with less tire width. Those people with firestone clown shoes seem to get them to clear.
 
Mt90 is a 130 tire.

Just to put this all in perspective with regards to the "rim width charts" out there, some bikes come with a 2.5" rim and a 130 tire from the manufacturer.

I'm thinking 130 may be too wide for the 2.15 though. Also, remember that when you pinch a tire to fit a too narrow rim it really rounds the tread area of the tire. What i'm saying is that even though it's a 130 it may look no wider than a 120 and perform much worse than a 120.
 
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Thanks that all makes sense. I was worried most about the chain rubbing.

So, if I can ask some advice, can you guys point me toward a tire that fits? I don't know if I'm just not learned enough, but like I said, I can't seem to find any 16 tires that fit 2.15

Of course I really love white walls, but at this point I will consider any tire that lets me avoid a whole new wheel.

Thanks again
 
I have run both sizes and the 120 (stock size) does handle better. But if it's a look you are going for:)
 
I found a brand finally in that thread link that has a 110/90/16, although not whitewall. Just got back from the shop, and even the 120 sticks out quite a lot from the rim. Probably just gonna eat it, and get inexpensive tires that fit, and just deal with it. i built the frame to fit the wheel, so i think replacing the wheel isn't in the cards at this point.

Thanks guys
 
Just noticed you have a hardtail. Might as well go big, fits the look :) I will say if you are going big, get the avons. They are quality tires. Stay away from anything made from 'vintage' molds (firestones/coker/etc).
 

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