Author Topic: 120/90 - 18?  (Read 1515 times)

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Offline Tretnine

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120/90 - 18?
« on: September 22, 2009, 05:45:55 PM »
I went into the local honda shop today, and they didn't have any 110/90 18s. Will 120s work? How big can you go and what are the repercussions?
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: 120/90 - 18?
« Reply #1 on: September 22, 2009, 05:47:25 PM »
They will work on many bikes. What do you have? It's what I'm running on my 75 750F.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline Tretnine

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Re: 120/90 - 18?
« Reply #2 on: September 22, 2009, 05:52:17 PM »
I've got a 78 550. One of the guys in the shop there owns a 500 and apparently they looked as his bike and said, OH YEAH, that'll work.
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Offline GammaFlat

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Re: 120/90 - 18?
« Reply #3 on: September 22, 2009, 06:07:50 PM »
I found a wide selection at Tires Unlimited.  I had the tire in my hands in one day (shipped). 

They have the tire I bought in your size on this page: http://www.tiresunlimited.com/ALL%20TIRES/AVON/AVON%20MC/avon_am26_roadrider.htm
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Offline nrd2052

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Re: 120/90 - 18?
« Reply #4 on: September 22, 2009, 06:49:27 PM »
i am running that size on my 550 and it works well for me. I also have one step larger in the front. Seems to be great so far. The downfall is that you lose a bit off the line. my friend with his stock size tires can now consistently pull away from me off the line.

Offline TwoTired

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Re: 120/90 - 18?
« Reply #5 on: September 22, 2009, 09:51:50 PM »
The 120 will work fine when new.  But, it is too wide for the stock rim, which makes the tire tread over-crown with the increased pressure you need to stabilize the tire sidewall.
Over time and wear, the tire will square off and you'll be fighting the bars in turns to hold your turn line.  It will wear pretty fast, too.

Then you will rave about how much better your new replacement tire feels on the bike.  ;D

Many shops will be happy to sell you whatever they have in stock for your bike, whether proper, or not.

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Offline Beans

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Re: 120/90 - 18?
« Reply #6 on: September 22, 2009, 11:04:23 PM »
im running a 120 on the stock rim on my 75-550f.  don't like the way it looks but it works for now. thinking a wider rim is in need here soon.
Keep it shinny side up.

Offline Tretnine

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Re: 120/90 - 18?
« Reply #7 on: September 23, 2009, 05:59:12 AM »
Good info there, two tired. Once this bike is up and running I'll have a couple on the road. (actually it's up and running now, since it's titled and registered) But once I get my extra set of rims back with new, balanced tires, I'm hoping it will be drivable. There was so much wobble I couldn't break 40 without feeling pretty uncomfortable. With two bikes I might not get through enough tread over the course of a few years to make it that bad, and I do like to replace tires regularly.
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Offline BVCB650

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Re: 120/90 - 18?
« Reply #8 on: September 23, 2009, 07:10:28 AM »
It will be wider and taller than the OEM size. 9mm isn't that much difference in height, but a wider tire on the front might not be what you're after.
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