Thread: Tire size ..

Hi , I am running a 130 street rear on my CT . There is just a little interferance with the chain so I have decided to go down to a smaller 120. Is it preferable to go with a smaller tire up front 110 or is this just for looks. Could I run with 2 120's

You didn't mention the aspect ratio. Assuming 120/70 x 10, there's no problem running that size front & rear. The reason you normally won't see 130/70 x 10 on the front is that it's too wide for a disc brake with available triple trees.

sorry....I was running 130/90/10 in back & 120/90/10 in front. I thought I would switch my 120/90/10 to the rear & go with either a 120/9010 or 110/90/10 in front. Would it make much any difference 120 or 110 up front ?

I've always considered 120/90 x 10 the limit. That size offers some interesting tradeoffs. I like the idea of running a taller sidewall, especially on a lightweight bike, and the larger overall diameter (and with it, rolling circumference) gives more mph/rpm. On the downside, the speedo will read slower and you lose most of the adjustment range with the rear wheel. Aesthetically, let's just say it's in the eye of the beholder . Running a 120/90 rear and 100/80 front shows off the size difference dramatically, giving the bike a profile that's akin to a classic `23 T-bucket roadster...the "big & little" wheel profile. Intuitively, you'd expect squirrely handling; real world, these bikes handle best with the weight bias shifted forward. Turn-in really benefits from this.

You're going to buy another tire either way, but it's mainly down to personal preference.

IS 120/90X10 FITS to a ST70?

120/90/10 yes I have put front & rear no clearance issues. When looking at the bike it creates an illusion that the rear is larger than front. Probably because of the space between the front fender and tire makes the front tire look smaller. I have yet to ride the bike with this installation. But it should work out well.

Just fit new rims with 120/90-10 rear and 100/90-10 front.Took the bike out for a 20 mile ride,speeds up to 55 MPH,handles just fine with the 2 different tire diameters...........

There are some who claim that bikes handle better with narrower tires. I don't think there's enough difference between the sizes that will fit these bikes to have much of an effect. However, I have noticed that turn-in improves significantly with a slightly forward tilt and it's accompanying weight bias. If anything, I'd expect a "big & little" tire combo to improve handling.

Question for Honda 123. what kind of upper is on that front fork, it looks different from anything I have seen around.

When you say upper , I imagine you are talking about the mini fairing. It came out of ebay High/Low beam , & intergrated turn signals. Is not street legal DOT.