Current tire options for alloy wheels (tubeless tires)

[peterbaron]

Quote:
”….The 3% rule for tires stands as one of the most important guidelines in tire replacement.  Staying within 3% of your original tire's diameter ensures both safety and optimal performance when selecting new tires. This seemingly small percentage can make the difference between proper vehicle handling and safety….”

[Karidis]

https://cb1100forum.net/forum/showthread...211&page=2

The Speed-O-Healer app says it is 5.8% not 5 mph. I have CRS.

http://cb1100forum.com/forum/showthread....#pid340481

[Nachodaddy]

Hey, Karidis. It's good to see your name on here again. 

[Cormanus]

Thanks for the additional information, Karidis. I stand corrected.

[air-cooled fan]

I just installed the the Angel GT 160/60 on a standard 2014 so thank you to all for sharing all the tire options,

[Venteuri]

... Pirelli Angel GT Tires. The 160 will fit on the rear. If I recall the speedo will be off by 5 mph.

Is that right, Karidis? I don't understand precisely what tyre measurements mean, but I thought 140/80 and 160/60 ended up being the same diameter meaning the speedo shouldn't be out of whack. Of course, I may well just be displaying my ignorance, but I'm a long-term user of 160/60 rear tyres and I don't think my speedo reads differently when I run 140/80s.

The meaning of the tires is the width and % of the sidewall height in mm.
Example: 80% of 140mm = 112mm sidewall height (from floor to rim)

This is a very helpfull calculator:
https://www.calculator.net/tire-size-calculator.html

https://www.calculator.net/tire-size-cal...te#compare

[LucienLeFranc]

Thanks Venteuri for those links!  Better than the site I was using.

So, 140/70-18 vs. 160/60-18:

   

The 160 is almost an inch wider, but height is the same for practical purposes.

[Cormanus]

Yes. I kept thinking the stock tyre was 10/80, but it isn't; it's 140/70, so the difference is. as you say, negligible.

thanks for the link to the calculator Ventueri. That's really helpful.

[LucienLeFranc]

Actually, Kardis' brain is in better working condition than mine .

I now think it is correct that the speedo will be off.

What I failed to consider is that the 160 is meant to go on a wider rim, and so when you squeeze the tire onto the 140 rim, the tire will push the diameter outward.

Kardis had an issue posting pictures here, so he sent me info via email--Ill post it shortly.

Thanks Kardis for patiently setting me straight!

---

   

This information does make me question using a 160 on our bikes, however.

Since the 160 is squeezed onto the rim and therefore pushes the tire outward, increasing the diameter, won't that also round the profile of the tire?  A 160 tire on a 160 rim will have a different (flatter) profile that contacts the road surface than a 160 tire on a 140 rim.

If this is right, then I may stick with 140 tires as long as they are available, since a 140 tire on a 140 rim will preserve the profile that the tire designers intended. A "deformed" profile due to being on the wrong width rim maybe has a similar effect to a deformed profile due to running too low or high of tire pressure?  The contact patch might be longer and narrower on straights and would transition differently into corners?  At least other than the designer intended.

At least I think that's correct?  But my brain has failed me before (recently) so let me know if I'm off base on this.

I wonder if there's an online simulator that shows how much a tire is deformed where it contacts the road due to mismatching the rim to the tire by 20mm? Maybe it's not such a big deal.

Interested in hearing from you knowledgeable folks!

[Karidis]

I think this is so close that you will not notice any change, it's too close in height. I love the 160 and will buy another when this one wears out.