[zedro]

i know undersizing tires slightly is common, but within the same lineup and to such a large degree is freakin rediculous.

i've been running Comp 32s front and back, which are rated at 2.8 but measure 2.75" on my (new and awsome) 823s, which is perfectly reasonable. But now i just installed a new Comp 16 2.5 for the rear, and the damn thing measure 2.25"! So instead of the quarter inch difference that i wanted, i get a silly whole half-inch difference between the front and back. Next to the Comp 32, it looks like a damn XC tire. I wonder if the difference will be that noticible...

On the bright side, these UST tires are stupid easy to mount and inflate on the 823s. Rubbed a little Stans on the bead, slipped right on and used my floor pump. The brand new Comp16 inflated right away, but my slightly used 32 needed some messageing

 

[spookymilk]

dosn't matter how big it is, just matters how well it hooks up, if I there was tire that was a 2.0 but hooked up as well as a 2.8 Michie, I'd buy it, cause it would drastically reduce rolling resistance.

PS- I have a Comp32 and it makes my 2.5 Nevegal look like a semi slick so it's all good

 

[thaflyinfatman]

I hate it even more when they're oversized. I got some DMR Moto 2.2s only to find out that they're actually nearly 2.5s...

 

[GrahamKracker]

It's cool. The Comp 16 is one of the best tires made. Take it out and see how it grips, I don't think you'll be disappointed, unless your conditions are waaaay different from mine. (Santa Cruz, CA)

 

[zedro]

i'm just worried that the difference in width will cause them to track differently. It does look like a seriously grippy tire.

If the 2.5 is a 2..25, then i wonder how small the 2.2 is....

 

[Acadian]

i'm just worried that the difference in width will cause them to track differently. It does look like a seriously grippy tire.

If the 2.5 is a 2..25, then i wonder how small the 2.2 is....

smaller, but not THAT much smaller.

I think it's just that you are too used to that big bubbly Comp 32 I run a 2.5" Comp 16 on the front of my bike and I find it wide.

Like thaflyinfatman said, I think it's worse when they are WIDER than the stated size. If you think the Michelin are undersized, stay away from Maxxis

 

[dump]

i'm just worried that the difference in width will cause them to track differently. It does look like a seriously grippy tire.

If the 2.5 is a 2..25, then i wonder how small the 2.2 is....

how about you go ride the damn thing & then bitch

 

[McGRP01]

Sizing wise, Panaracers are worse!!

 

[neversummersnow]

Chris K always runs 2.7/2.35 combo, so that's not too much different than what you are talking about...i bet you like it!

 

[zedro]

how about you go ride the damn thing & then bitch

guess i just feel cheated by the undersizing, like your girlfriend musta felt....

 

[Softy]

I don't understand the arguement. It is science. The tire makers have no standard width rim to measure from. The same tire mounted on different width rims will yield widely spaced results.

Put a 2.5 on an XC hoop and it will measure near 2.2. It will stand an inch taller than a 2.0 , raking out he head angle.

The arguement that his tire is fivehundredths of an inch narrow is plain stupid.

 

[zedro]

I don't understand the arguement. It is science. The tire makers have no standard width rim to measure from. The same tire mounted on different width rims will yield widely spaced results.

Put a 2.5 on an XC hoop and it will measure near 2.2. It will stand an inch taller than a 2.0 , raking out he head angle.

The arguement that his tire is fivehundredths of an inch narrow is plain stupid.

not sure what your getting at, the same rim is being used vs. the Comp32 but twith a whole size under....anyways, gonna try and use the smaller size to my advantage by shortening the wheelbase and slackening the headangle. Was just really surprised to see such a difference with the same manufacturer and rim setup. I still love Michies...

although i just noticed that the tire is defective with cracks all along the casing which werent visible when the tire was deflated. I'll get to see if a new one turns out to be the same dimensions.

 

[Jeremy R]

Yo Zed,
Riding those tires are alot more fun than measuring them.
The reason that your tires measure small is bacause of those
weak narrow 823's. A regular size DH rim, they measure spot on.
Also, the Comp 32 is a straight up beach ball.
Those tires have such a high amount of air volume, it makes everything else look small.
Those tires are a giant crutch, and should only be used on super fast and rough courses. I say this because they are addictive. They give you so much traction, it will make ya want to run them all the time.
I had to use a "cold turkey" approach to not running them unless I really needed 'em. It was quite painful. :dancing:

 

[Castle]

Zed, I just mounted a set of Comp 16's 2.5's on MTX hoops, and I measured 2.3 even...

these run a good bit smaller than my minions and highrollers which actually measure right at 2.5 on these hoops, I was expecting a 2.5 atleast from michelin! I agree with the let down.... I guess I'll find out if they feel squirley and twitchy when my fork gets here..

I guess Maxxis tires really aren't all that undersized after all.......

 

[zedro]

Zed, I just mounted a set of Comp 16's 2.5's on MTX hoops, and I measured 2.3 even...

these run a good bit smaller than my minions and highrollers which actually measure right at 2.5 on these hoops, I was expecting a 2.5 atleast from michelin! I agree with the let down.... I guess I'll find out if they feel squirley and twitchy when my fork gets here..

I guess Maxxis tires really aren't all that undersized after all.......

heh, just installed the replacement Comp16, and and its even a tad smaller than the defective one at a smidge under 2.25" lol.....oh well.

The 2.5 Comp24s my buddy runs seem to be spot on though. I guess its because this Comp16 size is new, my lbs noted the newer Michy models seem to run quite a bit smaller now.

 

[BrokenSpoke]

zedro, i had the same suprise with mine, my new one where smaller then last years, even tho they where the exact same...i know it sucks at the first look, but when you ride them you dont notice, they are just insane when you ride neaky:

 

[Acadian]

heh, just installed the replacement Comp16, and and its even a tad smaller than the defective one at a smidge under 2.25" lol.....oh well.

Defective one? what was wrong with it?

I guess its because this Comp16 size is new, my lbs noted the newer Michy models seem to run quite a bit smaller now.

the 2.5" Comp 16's aren't really new - they've been around for a while now.

Are you sure they run smaller? I have a few at home, I'll have to compare.

 

[zedro]

Defective one? what was wrong with it?



the 2.5" Comp 16's aren't really new - they've been around for a while now.

Are you sure they run smaller? I have a few at home, I'll have to compare.

it had some cracks in the casing, but it suspiciously looked like someone gouged some box cutters into them.

The 2.5" Comp 16s are newer i should say i guess. On the same rims, they run relatively quite a bit smaller than the Comp32s and 24s

 

[ChrisRobin]

it had some cracks in the casing, but it suspiciously looked like someone gouged some box cutters into them.

The 2.5" Comp 16s are newer i should say i guess. On the same rims, they run relatively quite a bit smaller than the Comp32s and 24s

Weird, I just measured mine and my comp32 is 2.75 from edge of tread to edge of tread and my comp16 is just a tad under 2.5. I found the comp24 to be pretty much the same width but lower profile.

 

[Castle]

Weird, I just measured mine and my comp32 is 2.75 from edge of tread to edge of tread and my comp16 is just a tad under 2.5. I found the comp24 to be pretty much the same width but lower profile.

which hoop are you using?

 

[zedro]

Weird, I just measured mine and my comp32 is 2.75 from edge of tread to edge of tread and my comp16 is just a tad under 2.5. I found the comp24 to be pretty much the same width but lower profile.

thats really odd. Maybe they're mis-badged 2.2s? I would love to try it as a front but as it is its too narrow.

 

[Jeremy R]

thats really odd. Maybe they're mis-badged 2.2s? I would love to try it as a front but as it is its too narrow.

That's odd man.
One thing that I have always noticed though is that the comp 24s are always wider than the comp 16s in both 2.2 or 2.5
I just assumed that it was because of the tread pattern, or maybe they are more narrow to cut through the soft stuff better. Either way, the 2.5 comp 16 makes a great front tire. I even ran that at Mt. Snow.

 

[punkassean]

I have a Maxxis 2.5" High Roller on a 521, and Michi 2.5 hotS on an 823 and the Michi is considerably wider. The hotS and the comp 16 have the same tread and are both 2.5", right? I am surprised top see that the Michi measured only 2.3" for you...I will try to get a # off of mine tonight for comparison.

wierd??? I always though Michi's measured larger than stated and Maxxis smaller...

 

[zedro]

The hotS and the comp 16 have the same tread and are both 2.5", right?

its the Comp24 that has the same tread as the HotS, both in 2.5, exept the HotS is lighter (2.5 XC tire....weird). The 16 doesnt have a brother.

 

[punkassean]

is the comp16 the high roller looking tire (although Maxxis copied Michi's design)? Either way it is stupid that Michi would have two separate 2.5" tires that measure different. Shouldn't they use the same casing???

 

[zedro]

is the comp16 the high roller looking tire (although Maxxis copied Michi's design)? Either way it is stupid that Michi would have two separate 2.5" tires that measure different. Shouldn't they use the same casing???

well the lbs said they noticed 'the Michies running small', so maybe they changed the design and casting mold, ie. the older batches may be wider?

unless its a mis-labelled 2.2 (since it measure 2.25"), but thats embossed on the casing, which i assume is part of the mold...

i think i'm gonna contact Michelin about it.

 

[BrokenSpoke]

zedro, its pps, i had the same problemes with my new michelins to, even the 2.8 one(i never remember the numbers) is smaller, could it be because some frames had problemes with tire clearence? that i dont know, all i know is they ride as good as my other set and when riding you dont notice the difference

 

[zedro]

zedro, its pps, i had the same problemes with my new michelins to, even the 2.8 one(i never remember the numbers) is smaller, could it be because some frames had problemes with tire clearence? that i dont know, all i know is they ride as good as my other set and when riding you dont notice the difference

hey man, and guess what? i installed the damn thing backwards again! wtf is wrong with me....

 

[xy9ine]

i'm just worried that the difference in width will cause them to track differently. It does look like a seriously grippy tire.

If the 2.5 is a 2..25, then i wonder how small the 2.2 is....

i'm running 2.2's on tioga factory dh rims; the casing measures about 2", but the knob width is just a hair under 2 1/4" - (spot on @ 2.2). these tires are amazing, btw. they wear fast, but stick in a wide range of conditions - very impressive for a skinny tire - doesnt really leave me wanting for anything fatter.

 

[BrokenSpoke]

hey man, and guess what? i installed the damn thing backwards again! wtf is wrong with me....

HAHAHAHA you should of let a qualified mechanic do the job

 

[Erickson]

Howdy all,

Leif from Michelin here...

I just wanted to chime in and give as much info as I can on this discussion.

OK, first a few points to remember when measuring tire width.
- There are two places to measure a tire when determining width. The first would be the casing and the second would be at the outermost part of the knobs.
- Rim width and rim profile does affect tire width.
-Tires do stretch. Measuring a tire 5 minutes after mounting it for the first time will be different than measuring it a week after it has been inflated.
-Pressure makes a difference also. Measuring a tire at 20 psi vs. 50 psi will affect your results also.


For the record, the molds have not changed. The Comp 24.1 2.2" is the same exact tire it was 4 years ago as is the Comp 32, Comp 16, etc. There has been no change in the molds in any size over the years.


There is a standards organization for rim and tire manufactures which we follow in production of all of our tires. ETRTO (European Tyre and Rim Technical Organization)


I only have a few tires mounted up in my office at the moment but I do have a Comp 16 2.2" mounted that was a display at Interbike last October. It is mounted on a Mavic D321 at 16.5 psi. Using calipers to measure, it measures 54.1 mm at the casing and 55.8 mm at the widest point at the knobs. Converted it measures 2.13" at casing and 2.197" at the knobs.

I do not have a Comp 16 2.5" or a Comp 32 2.8" mounted in the office but I do have them mounted on the truck that goes to all the NORBA nationals. I will try to take a few measurements at Idaho and post my results if people are interested.

If you have any more questions or have any more input feel free let me know.

Leif Erickson

 

[binary visions]

Howdy all,

Leif from Michelin here...

Damn it's nice to get information straight from the source

Thanks!

 

[Showtime]

Zedro,

I have found that the Michelins do stretch a bunch. I have a set of the Comp 24 in a 2.5" and a friend of mine got a brand new set. His looked like XC tires next to mine. After about a week of being inflated and ridden, they were the the same size as mine. I would suggest pumping yours up to about 60 PSI and go cruise around on them, they will probably stretch out a bunch.

 

[punkassean]

Howdy all,

Leif from Michelin here...

Leif Erickson

Leif Erickson, the mighty viking reincarnated??? I'll be damned! gone from conquering villages around the globe to conquering DH courses around the globe!

Thanks for the info...straight from the horses mouth!

 

[James | Go-Ride]

Zed,

We thought the Comp32 shrunk down a little bit also in the last year, but according to the post from Leif that's not the case. That aside, from our measurements the 2.5 Comp 16 measures about 2.35 on an Atomic Trailpimp at 30 psi, and the 2.2 measures almost 2.2 exactly in the same configuration. The big difference though is the size of the casing, the 2.5 casing is about 0.5" taller than the 2.2 casing, which is a pretty huge leap. The tire has a lot smoother ride with the bigger casing and better traction, due to both the width and the increased casing volume (with a larger casing tire, putting pressure on the wheel in situations like impacts and cornering affects the internal air pressure of the tire less, so the contact patch is bigger).

 

[punkassean]

James.
there must a lot of clocks over there at Go-Ride headquarters....

Cuz y'all sure seem to know exactly what time it is!!!

HAHAHAHAHAHA!!

Good info, thanks!

 

[Sgt Brown]

I just used a micrometer to mesure my tires. They have been mounted for about a month on Mavic 3.1 Tubeless, and are inflated to about 25 psi rear and 22 psi front but I originally inflated them to 60 to seat. I took the mesurement from the wides part which was the casting. Here is what I came up with.

Comp 32 2.8 = 2.5"
Comp 24.1 2.5 = 2.3"

 

[DIRTWRKS]

Hi,

I was wondering if Leif could comment on what Michelins position is on running the comp 16 in reverse direction to that indicated on the sidewall. Most riders on this site seem to prefer it that way

I have been conducting some of my own trials and I feel that it in the front the 16 hooks up better for me in the normal direction especially through rocky and slick terrain, it's almost as if there is more rubber in contact with the ground running it in the normal direction. In the rear I did not notice much of difference either way.

 

[punkassean]

Hi,

I was wondering if Leif could comment on what Michelins position is on running the comp 16 in reverse direction to that indicated on the sidewall. Most riders on this site seem to prefer it that way

I have been conducting some of my own trials and I feel that it in the front the 16 hooks up better for me in the normal direction especially through rocky and slick terrain, it's almost as if there is more rubber in contact with the ground running it in the normal direction. In the rear I did not notice much of difference either way.

I have wondered the same thing about the comp 24...

 

[Erickson]

I agree, running the Comp 16 and the Comp 24.1 opposite of the directional arrow will offer better braking and a faster rolling tire. Better breaking and faster rolling tires are usually preferred over better climbing traction while riding/racing downhill.
When I mount the Comp 16 and the Comp 24.1, I mount them opposite of the directional arrow. I do recommend mounting the Comp 32 and the Mud 3 using the sugestion of the directional arrow.

Any other questions or comments, let me know.

Leif Erickson
www.TeamMichelin.com