The Honda PCX / Forza / ADV150 / SH Forums

Hey all,
I know a 140/70-14 will fit the rear but will a 120/80-14 clear the front as well? I'm going with pirelli diablo tires.

Try it and find out. I kind of doubt it will fit but no one else has tried that size.
I would run that size if I knew it would fit.

Sorry Dasshredder, I meant 120/70-14. I have ordered both tires in pirelli diablos. We'll see how they stick 8D

, post some pics when you get them on.

I will. I'm taking a summer physics course right now and according to the laws of physics the wider tires should increase stability and reduce the angle of lean needed to turn as far. I'm really looking forward to that as most of my riding is highway at 65+ mph.

Will not the wider tread negatively impact fuel consumption?
Or do the Pirelli tires have a larger circumference to compensate?
Or, does the PCX have sufficient torque to overcome the larger tire circumference at the lower RPM?

The 140/70-14 is just large enough to correct my 1mph at 70 fast reading speedometer. At the same time the wider contact patch shouldn't hurt that much. I'll let everyone know once it's arrived and mounted.

I really don't like this idea as it distorts the tire profile. It will give you a more squared profile meaning more contact patch on the straights, but dramatically less at partial lean and beyond. If you rarely lean it over, it may not kill you. Either way, the wider tires are usually rated for higher top speed, and if nothing else, the wider tread adds a couple lbs of rolling weight which will have a neg effect on fuel econ, hill climbing ability, and acceleration.

When you do mount the tires, please take close-up pics from directly behind the tire so we can see the tire profile.

Will do. The extra weight will also add more stability and theoretically will also allow less lean for the same turning.

Hello all, my front and rear tires shipped separately. I have installed the front tire. I'll see if it "grows to the rim" but for now I'm content. The tire currently has less than five miles on it so it's too early to tell how it will grip.

Here are the pics I promised.

At slight lean angles the bike will feel 'tippy' but as lean angle increases the effect will not worsen. Oversteer will be a serious problem so be careful. On the Interstate, with the contact patch now shorter relative to the width, the bike will feel like you are riding on square tires and side wind effects will be dramatic.
Increased rolling weight will lengthen stopping time and distance.
Increased wind resistance will likely increase fuel consumption. On a Triumph Rocket III the effect would not be measurable. On a bike with 13HP it will be.
The narrowest wheel a 140 profiles for is 2.75. On the PCX150 the 1.85 front wheel pinches the profile sufficiently as to make a blowout....uh...imminent.
You must have mounted the tire yourself; it's hard to believe any shop would have done it.
Still, an interesting experiment. I'll wager you'll have that 140 off in a week - by choice or not.

The 140/70-14 will go on the rear. Multiple members have mounted them. I put a 120/70-14 on the front an had it mounted by my local Honda dealer. You misunderstood.

Hey everyone, the GAP seen in the first picture is actually lined up wih the outter profile of the tire. It's just not visible wih my cell phone camera.

Tribpreper wrote:At slight lean angles the bike will feel 'tippy' but as lean angle increases the effect will not worsen. Oversteer will be a serious problem so be careful. On the Interstate, with the contact patch now shorter relative to the width, the bike will feel like you are riding on square tires and side wind effects will be dramatic.
Increased rolling weight will lengthen stopping time and distance.
Increased wind resistance will likely increase fuel consumption. On a Triumph Rocket III the effect would not be measurable. On a bike with 13HP it will be.
The narrowest wheel a 140 profiles for is 2.75. On the PCX150 the 1.85 front wheel pinches the profile sufficiently as to make a blowout....uh...imminent.
You must have mounted the tire yourself; it's hard to believe any shop would have done it.
Still, an interesting experiment. I'll wager you'll have that 140 off in a week - by choice or not.

Oversteer on a 10hp step thru?

You must have fitted a variator....

Tribpreper wrote:At slight lean angles the bike will feel 'tippy' but as lean angle increases the effect will not worsen. Oversteer will be a serious problem so be careful. On the Interstate, with the contact patch now shorter relative to the width, the bike will feel like you are riding on square tires and side wind effects will be dramatic.
Increased rolling weight will lengthen stopping time and distance.
Increased wind resistance will likely increase fuel consumption. On a Triumph Rocket III the effect would not be measurable. On a bike with 13HP it will be.
The narrowest wheel a 140 profiles for is 2.75. On the PCX150 the 1.85 front wheel pinches the profile sufficiently as to make a blowout....uh...imminent.
You must have mounted the tire yourself; it's hard to believe any shop would have done it.
Still, an interesting experiment. I'll wager you'll have that 140 off in a week - by choice or not.

Mgalutia did the tire "hairs" touch the fork like mine did?

dasshreddar wrote:

infant

Hi Tribpreper, thanks for chatting here. First let me say that I know very little of what you guys speak of in "tire sizes and fitting." However, I'm always intrigued by tire chat. If sizing up my tires on my scoot would be beneficial to comfort and safety I would seriously consider doing so. But if dangerous, I'm out of the game! Honda chose our tires for a reason. Do I know why? Not really. Safety? Balance? Comfort? Traction? And mix of Elements.
With all that said, you yourself seem very knowledgable about the topic and I'm interested. I appreciate all opinions and experience on this topic (whether you diss each other or not). In fact ya'll make me laugh sometimes (I really enjoy that)
If you don't mind me asking,...Are you by any chance in the tire industry or something job related to tires? I've had Michelin tires on every vehicle I've owned, I trust them. Folks here really seem to like the City Grips on their PCX's and sizing up has been tested quite a bit as well. Not by me (yet) though
Thanks for your input.

Dasshredder I havn't fitted the new rear tire yet. It comes in the mail today by UPS. My fron tire the hairs brushed the rear of the front fender and were gone by 30 miles. I scrubbed the tire with dish soap and a scotch brite pad yesterday to get the majority of the slick crud off. It's already scuffed in pretty well as I have almost 50 miles on it. The front tire grips and rides great.

As for more mass reducing stoping power, I already have upgraded front pads and rear shoes so I can stop significantly shorter than normal anyway. The front is requiring no extra effort. As soon as both new tires are on I'll update everyone on the stability feel.

120/70 front and 140/70 back seems to be pushing the limits. Is there some alternatives in between this extreme and the standard 90/90 and 100/90?