Low profile MTB tyre...!!!!!

[O'l Timer]

Gooday all. Just replaced a tyre on my E-Trance. Replaced my rear 2.6 x 29" Maxxis Assegai with a 2.6 x 29" Vittoria E - Mazza. When my original front tyre is sitting next to the Vittoria rear there is a distinct visual difference. Thought I would measure the tread and using calipers across the outside Knobblies found the Vittoria was 60mm (2.36") @ 35psi and Maxxis measured 67mm (2.6") @ 35psi. I run 25 psi front and 30 psi rear but thought I would pump up to Vittorias max PSI of 35 as a datum point. The rolling distance of the Vittoria was also 76mm (3.0") shorter than the Maxxis. Don't know if anyone else has noticed similar with other brands but will be interesting to see if I notice any noticeable differences when I go up in the hills in Mid Wales next week. The gearing I would imagine will be out....don't know!!!

 

[steve_sordy]

@O'l Timer I have read that some brands vary in their claims about width, which is why the reviewers measure the width to check. So it must be a thing.

Diameters are something else, in that it seldom gets a mention.

It doesn't seem that long ago since 27.5" wheels were taking over from 26ers. At the time my mate had the same tyres as me, Continental Trail Kings 26x2.2. He bought a new bike and it came with Schwalbe 27.5x 2.25. (The width is from memory).
I asked him how he was getting on with the new bike and especially the wheel size. He replied that he couldn't tell the difference. I had been messing with my fork set up and just happened to have a 36" tape measure with me so I measured our respective wheel diameters. My 26er was 26.75" and his 27.5er was 27.25". No wonder he couldn't feel the difference, they were less than 2% apart! Even if the declared wheel diameters were accurate, they are still only less than 6% apart. (Compare that with an average gear shift of 15%.)

 

[O'l Timer]

Interesting....I don't think that there are any British Standards relating to wheel / tyre sizes so makers can really put any figure down that pleases them. Obviously tyre diameters are more critical for fitting onto rims. I had a non-foldable Magic Mary on my previous Trance that took about 5 hours to fit necessitating the purchase of a track pump "blaster" type and a strap around the tyre to enable me to seat the bead.....foldable type only for me. Really...in my case I have a Mullet E-Trance I suppose.....lol.

 

[O'l Timer]

Just been looking at a review on Bike Radar for an E-Mazza of 2.4" width tyre. My 2.6" doesn't look too far away from a 2.4" tyre. Perhaps Vittoria use the same widths rather than make larger moulds...lol

"The 2.4in Enduro and e-MTB casing tyre measured 59mm/2.32in on both the 27.5in and 29in wheels when inflated to 26psi, while the 2.4in Trail casing tyre measured 61mm/2.4in exactly on both wheel sizes when also inflated to 26psi."

 

[steve_sordy]

@O'l Timer I am not suggesting that the internal tyre diameter (at the bead) varies, well not by much. But the outside diameter seems to vary a lot. Some tyres adopt a balloon shape and therefore measure bigger, some adopt a flatter profile; and of course the tread will have an impact (think big knobs vs a semi-slick).

And then there is the impact of rim width!

 

[O'l Timer]

Think that may be my limiting factor......rim width. Taken from MTBR review on line....
" The 2.6 Mazza is 63.37 mm wide with a 33 mm width rim."
Looked up my bike specs and see that my rims are 30mm wide. So rims are "pulling" in my tread width.....but why are my Maxxis not doing the same. Think i'll stick to just riding and don't look to deeply into things.....lol