140 rear tire

[Bills dad]

So I got a stock 130/70-17 on the rear of my ex250 that the previous owner decided to burn out till it's got a sweet flat surface, so I'm looking to go up a size wider to the 140. I understand the clearance and all, I would like opinions on a good tire in that size and where I might find it. Out here most everything is purchased via Internet. Im sure this has been discussed many times over but your input would be appreciated!!!

[DannoXYZ]

If you're looking for basic commuter tyre, Kenda K671 is heavy-duty cruiser model in that size which will get you 15-18K miles.

If you're going on racetrack occasionally, Bridgestone BT-45 is good dual-compound tyre with softer edges. Good for 10-12K miles.

Whatever tyre you get, DO NOT inflate to max-PSI rating on sidewall (unless you weigh 450-lbs). Use pressure listed in owner's manual for bike. About 29-33psi works well for most people. Gives good combination of grip and tyre-life.

[Bills dad]

It's more for in town however would like the capability for it to run well if I have the occasional desire to preform, and does good in wet conditions if absolutely necessary. I don't weigh more than 150 so not much weight between me and the bike.

[Triple Jim]

My BT45s work well on my 250 for spirited riding.

[Bills dad]

Thank you for your time and help!

[Triple Jim]

You're welcome, Craigen. I don't mean to suggest that I recommend going to a larger size though.

[Bills dad]

I totally understand. I don't want to get carried away with the size but one size up seems reasonable

[Triple Jim]

Did you check the recommended rim width for the tire you're thinking of getting? With one 130 tire I bought to replace a 120 on my Moto Guzzi, I found that it was designed for a wider rim, and when I installed it on my narrower rim that was the right width for the 120 tire, the 130 was exactly the same width as the 120 had been, as measured with a caliper. The only difference turned out to be more tread wrap, creating tread that never touched the pavement.

[Bills dad]

Everything I've read says 3 1/2 wide which is the stock

[Bills dad]

3.5 to 4.5 inch wide rather sorry.

[DannoXYZ]

You may find that with 3.5" rim, that tyre won't be able to roll onto edges. Effectively giving you only 130mm of useable width anyway. An easy swap to 4.0" rim is Ninja 300 rear wheel. Ninja 650R (ER6N) can donate a 4.5" wheel, but will need some machining of wheel and spacers.

[vkuchhal]

I have upgraded to 140 sections after the the stock tire from IRC was replaced by pirelli sports demon and now on my 3rd set of tire without any modification.

I have a Ninja 250 2010 model done over 55k KMS.

[Ralgha]

Why do you want a 140 tire instead of 130? Visually you won't notice a difference, and it's not going to improve the handling. Not saying you shouldn't, just know what you're getting.

[Bills dad]

Well I have the 140 on now for a few days, and to report it feels good. Holds true, and holds great in the corners. An inch wider, was wone ring how that would work out. It is taller but looks and preforms good. (So far) again hasn't been a week yet and I'm used to the balled and flat burnout tire it came with.

[Triple Jim]

Auto-correct?

[Bills dad]

Correct!

[mitchman]

I replaced my rear with the 140. Bike feels similar. However, if you are leaning a lot (racetrack), you will never use the whole rear tire, if keeping the stock front tire (110). Well at least this is the case with my tire combo (110 front, 140 rear. Tires are pirelli diablo rosso.

Check the image of my tire wear and you will see what I am talking about. Anyway, for the road use... I don't notice any major difference. Just go with the combo you get/like.

[DannoXYZ]

Originally Posted by mitchman

I replaced my rear with the 140. Bike feels similar. However, if you are leaning a lot (racetrack), you will never use the whole rear tire, if keeping the stock front tire (110). Well at least this is the case with my tire combo (110 front, 140 rear. Tires are pirelli diablo rosso.

Check the image of my tire wear and you will see what I am talking about. Anyway, for the road use... I don't notice any major difference. Just go with the combo you get/like.

Yup, you'll also create balance mismatch at limit that I find dangerous. Front-end will let go before stickier 140 rear, which is much, much more difficult to catch than rear going out first like with stock sizes.

One time at Thunderhill East, I got impatient in turn-2 and whacked throttle wide-open while completely leaned over. Guess what? Yeah, I crashed, but how it happened is annoying. Rear 140 tyre didn't spin, bike didn't exit turn rear-first or high-side me. Rear continued to stick even with full-throttle at full-lean!!! However, front tyre just let go with no warning! Having stickier rear-tyre than front is scary! If I was going to upgrade tyre-size, it would be front first. More grip in front is so much safer and easier to control when back-end slides first.

[mitchman]

Originally Posted by DannoXYZ

Yup, you'll also create balance mismatch at limit that I find dangerous. Front-end will let go before sticker 140 rear, which is much, much more difficult to catch than rear going out first like with stock sizes.

One time at Thunderhill East, I got impatient in turn-2 and whacked throttle wide-open while completely leaned over. Guess what? Yeah, I crashed, but how it happened is annoying. Rear 140 tyre didn't spin, bike didn't exit turn rear-first or high-side me. Rear continued to stick even with full-throttle at full-lean!!! However, front tyre just let go with no warning! Having stickier rear-tyre than front is scary! If I was going to upgrade tyre-size, it would be front first. More grip in front is so much safer and easier to control when back-end slides first.

True, it is very dangerous on a track. Happened to me few times before finding out that the front tire is at max lean. Luckily without crashing. I was sure that there is something wrong with a suspension setup. Then I noticed tire wear... How did you solve the issue? You upgraded the front tire as well or just went to stock rubber dimensions?

[DannoXYZ]

Originally Posted by mitchman

True, it is very dangerous on a track. Happened to me few times before finding out that the front tire is at max lean. Luckily without crashing. I was sure that there is something wrong with a suspension setup. Then I noticed tire wear... How did you solve the issue? You upgraded the front tire as well or just went to stock rubber dimensions?

I went to Dave Moss for some help. He softened front-end with little less spring-rate and slightly less damping and stiffened up rear end. We also installed wider 17x3" front wheel to improve front traction.



Along with wider rear wheel, I can now reach edges of both tyres at same time. Much more balanced handling and sliding at limit can be managed with throttle much, much easier and safer.