110/80-14 or 100/80-14 for front tire?

[Mel46]

As everyone knows, I have a 2013 version of the PCX. I have a little over 5800 miles on the front tire now. It is the original tire that came on the bike when I purchased it new. I think it is about time to change it.

I changed out the rear to Michelin City Grips with the standard recommended size a while back.

I have read on here somewhere that a larger size front tire is more stable. I have also noticed two sizes that seem to be discussed alot. These are 110/80-14 and 100/80-14. I haven't a clue as to which tire size is preferred the most, but I do want to stay with Michelin City Grips. Anyone have any experience with these sizes?

(Standard tire size is 90/90-14)

[gn2]

Get the standard 90/90, anything else is the wrong size.

[Cube]

I believe the 2018s come with 100/80-14 now.

[Eiron]

The 100/80-14 is going to be slightly (10mm) wider but maintain the same outer diameter as the 90/90-14.
The 110/80 will be 20mm wider and a little larger (14mm) in diameter. If the speedometer and odometer are driven off of the front wheel, this will give you incorrect/lower readings. (Are they driven off of the front wheel? I don't know if they are or not.) This slightly taller front wheel height might also affect handling/geometry, but then again you might not notice.

[Oyabun]

Eiron, the speedo (& odo) pickup is in the gearbox, not the front wheel. So as long the rear wheel diameter is not changed, changing the front wheel will not change the readings.

[Mel46]

I noticed that some websites have a 100/90-14 in stock. Since the standard front for my year is 90/90-14 would that size have any effect on the front or the ride?

[gn2]

Not just size that matters, make sure its a front or a universal.
Never use a rear on the front and vice versa.

[Mel46]

I just came across this site. Looks like this size is front or rear.
https://www.jpcycles.com/product/166-67 ... upEALw_wcB

[Mel46]

Now if only I can find one that will fit my bike...hmmm.

[Eiron]

Oyabun, thanks, I wasn't sure.
Mel, tire sizes are listed as Width#/Height%. So a 90/90 tire is 90mm wide but only 90% tall (81mm).

My 2015's stock IRC tires are 100/90 rear (100mm wide X 90mm tall) and 90/90 front. A 100/80 tire would maintain my front diameter with its 80mm height, but would be 20mm smaller diameter (2x tire height difference for the diameter) on the rear. A 110/80 (88mm tire height) would be a closer match for the rear.

[homie]

I see the motorcycle superstore no longer has Michelin 14's of any size. I guess it might be difficult to find City Grips for PCX right now. There have been shortages before for new Mich'es one or the other but neither front or rear is available today.

[Mel46]

So, when Honda went to 110/80-14 for the 2018 model, how does that compare to the 90/90-14 that the 2013 model has? I was thinking that it would be better on my model because Honda did it on their newest model. Is that an error in my thinking?

[homie]

Mel, the 90/90-14 was the stock front tire/tyre/terr if i'm not mistaken. So a 110/80-14 would fit nicely, it would be wider but not as tall. Since its on the front you wouldn't put your speedometer off so you could do that but it would actually be wider than the stock rear tire/tyre/terr which was 100/90-14.

Disclaimer on this information, you need a second opinion on this. I know you don't put rubber made for front on the back and vs-versa because of thread patterns designed to shed water and gather up when braking. If you ever noticed thread patterns on motorcycles are opposing in angles... critical to staying alive.

[Eiron]

homie, did you mean 100/80? (The 100/80 would be 1mm shorter.) The 110/80 would be a bit taller than stock. The 90/90 is 81mm tall and the 110/80 is 88mm tall. It's also 20mm wider. I don't know if either this extra 1/4"+ height or extra 3/4"+ width will cause a clearance problem in the front fender?

Also, according to Honda's website, the 2018's are still using 90/90-14 front and 110/90-14 rear.

[homie]

homie, did you mean 100/80? (The 100/80 would be 1mm shorter.) The 110/80 would be a bit taller than stock. The 90/90 is 81mm tall and the 110/80 is 88mm tall. It's also 20mm wider. I don't know if either this extra 1/4"+ height or extra 3/4"+ width will cause a clearance problem in the front fender?

Also, according to Honda's website, the 2018's are still using 90/90-14 front and 110/90-14 rear.

Oh I never was the tire guy, I just refused to commit tire sizing to memory so I got nothing You know I'm still bouncing around on these over sized Mich's balloons.

[gn2]

http://www.avon-tyres.co.uk/motorcycle/faqs

[Mel46]

So now I am confused. Some members said that their 2018 PCX came with the different sized tires than what came with my 2013 model. Now you have pointed me to specs that say they didn't change the tire size. I guess, if I can't find the upgraded tire size I may just revert back to the original 90/90-14 size.

[gn2]

Reason you're confused could be that the different size tyres are on the third generation PCX which will be the 2019 model in the USA.
This model has a redesigned frame so probably different geometry hence the change in tyre spec.

[Eiron]

Well, I think changing the front from 90/90-14 to 100/80-14 would give you 1/2 of the ride quality change you're looking for. The width would be 10mm wider (probably perceptible) and 1mm shorter (imperceptible). Then, when you have to replace the rear next time, you could get a 110/80-14 to keep the same "wider rear" setup.

Or ditch all of the stress and just stick with the factory sizes!

[Cube]

It's common in the car world to alter the tire sizes (ie. wider and lower profile) for better handling so this would be what they call a 'plus zero' in some circles... wider tire with approximately the same diameter on the same rim diameter. Some car manufacturers even offer these 'plus' sizes as factory options. Based on eiron's numbers, the 110/80 is probably too tall, so the 100/80 being slightly shorter than stock is probably the sweet spot for this change based on what I remember of the process.

IIRC, the usual major concerns were that the tire might rub on something (like the fender) or that the existing rims are too narrow for the wider tire and will have too much of a round profile. I'd think this is less of an issue for a scooter/motorcycle because we start with a round profile. However, anything that alters the handling characteristics is ultimately up to the individual rider as they are the ones that will be healing if they choose poorly.

I'm personally interested in trying this change on my PCX once I wear out the existing front (forgot to check, but I think my 2018 is 90/90-14) as I don't like the narrow tire's tendency to catch grooves and cracks that my girlfriends Kymco 150 ignores.