OzVMX Forum

Clubroom => Tech Talk => Topic started by: Gippslander on September 01, 2014, 06:30:44 pm

Title: Tire sizes, confused
Post by: Gippslander on September 01, 2014, 06:30:44 pm
Getting confused,

I'm looking for some new Michelin S 12 tyres, I want 110/100-18 and on one of the ads I see the following:

"Up for sale is a brand new Michelin S12XC 130/80-18 (110/100-18 equivalent)"

Can anybody explain that to me, thanks

(fixed my typo  on the size I typed 100 and it should have been 110)
Title: Re: Tire sizes, confused
Post by: matcho mick on September 01, 2014, 06:51:07 pm
yep,makes sense if your'e pissed ;D, :P
Title: Re: Tire sizes, confused
Post by: JohnnyO on September 01, 2014, 07:02:39 pm
Michelin measure their tyre width from knob to knob and most other brands measure the width at the carcass.
A 130 Michelin is equal to a conventional 110
Title: Re: Tire sizes, confused
Post by: matcho mick on September 01, 2014, 07:05:30 pm
O
Title: Re: Tire sizes, confused
Post by: John Orchard on September 01, 2014, 07:09:29 pm
Yeh I have a Michy 110/90x18 on the back of the Kawa 400, miles too small.
Title: Re: Tire sizes, confused
Post by: Gippslander on September 01, 2014, 07:51:24 pm
Thanks John, couldn't work it out at all, doesn't make sense why they would do that just confuses the crap out of people anyway will probably give them a go, am looking for new tires for the 77 KTM 250, 110 on the back is probably about right, and they do the same on the front they say 90/90 is the equivalent of 80/100, but that's even sillier anyway they don't seem to list anything else if you go on their website they don't have a Michelin S 12 in 110/100 x 18 80/100 x 21, time to hit the fridge
Title: Re: Tire sizes, confused
Post by: Rookie#1 on September 01, 2014, 07:55:21 pm
Michelin measure their tyre width from knob to knob and most other brands measure the width at the carcass.
A 130 Michelin is equal to a conventional 110

Exactly, you'll find this on Michi and Metzler tyres, some others as well. I often get people who want to put a "130" on the back of their (insert any big bore here) and tell me it "has" to be a 130!! And "they're all the same", even after attempting to polite educate them often they're still walk out with tyre waaaay too small because "I know my bike mate" ???? oh well who am I to argue, after all.....what would I know  ;D ;)
Title: Re: Tire sizes, confused
Post by: Mick D on September 01, 2014, 09:05:55 pm
Getting confused,

Boy your confused, don't get me me started, so many experiences and what I thought at so many times what may have been knowledge ::) ::) at least 2/3 of life time of confusion,,,and it ain't over yet
Best try to explain in a moment when I'm not so busy drinking
Title: Re: Tire sizes, confused
Post by: Nathan S on September 01, 2014, 09:12:22 pm
Sometimes you buy a Michelin that has a sticker on the sidewall that has the "normal" size on it.

Michelin 120/90 = everyone else 100/100.
Michelin 130/80 = everyone else 110/100.
Michelin 140/80 = everyone else 120/100.
Title: Re: Tire sizes, confused
Post by: Mick D on September 01, 2014, 09:37:43 pm
so the confusion still goes on,,
sounds like you got to carry some sort of a manufacturers-conversion-equivalent card with you ::)
FFS

For  me the Confucius started way back in the 70's some where when I bought a 400x18 to replace a 400x18,,,,,,
and the new forker wouldn't clear the arm and chain >:(

Oh yeah well that's the way it is mate,,,,
some manufacturers measure the total width of tread and some measure the width of case, then add the tread, forkers.

So yeah,,,,,,,,,,,,,,,,,,,is there still some sort of manufacturer BETA, VHS sizeing thing still happening ?? 
Title: Re: Tire sizes, confused
Post by: SON on September 01, 2014, 09:50:02 pm
Maybe there is an advantage in buying from a shop where the guy knows the back wheel from the front
Title: Re: Tire sizes, confused
Post by: Gippslander on September 01, 2014, 09:53:59 pm
Thanks Nathan, can you do a comparo chart for the 21 inch front wheel tire sizes  ;D

Mick,  not sure I can laugh at the BETA VHS thing  because my memory goes back to when someone bought a cheap video player at the pub and went home beaming and the Mrs pointed out that BETA was  dead in the water
Title: Re: Tire sizes, confused
Post by: Mick D on September 01, 2014, 09:56:34 pm
 ;D ;D ;D ;D ;D ;D ;D

Well at least you got me laughin ;D ;D ;D
Title: Re: Tire sizes, confused
Post by: JohnnyO on September 01, 2014, 10:14:30 pm
Sometimes you buy a Michelin that has a sticker on the sidewall that has the "normal" size on it.

Michelin 120/90 = everyone else 100/100.
Michelin 130/80 = everyone else 110/100.
Michelin 140/80 = everyone else 120/100.
Yep that's correct..
It seems as though the enduro tyres use the different measuring system and the mx tyres the conventional way.
MH3 and MS3 are 100, 110 & 120 sizes
Title: Re: Tire sizes, confused
Post by: Mick D on September 01, 2014, 10:25:37 pm
Maybe there is an advantage in buying from a shop where the guy knows the back wheel from the front

Yeap, I reckon your right,,,
cant go past a fellow VMX racer and tyre specialist and all round good guy
http://www.localsearch.com.au/Warners-Bay,NSW/Two-Wheel-Treads-Motorcycle-Tyres/profile/uQ52 (http://www.localsearch.com.au/Warners-Bay,NSW/Two-Wheel-Treads-Motorcycle-Tyres/profile/uQ52)

https://www.facebook.com/pages/Two-Wheel-Treads-Motorcycle-Tyres/136639919846671 (https://www.facebook.com/pages/Two-Wheel-Treads-Motorcycle-Tyres/136639919846671)

http://www.whereis.com/nsw/warners-bay-2282/yellowId-14553213 (http://www.whereis.com/nsw/warners-bay-2282/yellowId-14553213)

Title: Re: Tire sizes, confused
Post by: tony27 on September 02, 2014, 06:14:59 am
Sometimes you buy a Michelin that has a sticker on the sidewall that has the "normal" size on it.

Michelin 120/90 = everyone else 100/100.
Michelin 130/80 = everyone else 110/100.
Michelin 140/80 = everyone else 120/100.
Yep that's correct..
It seems as though the enduro tyres use the different measuring system and the mx tyres the conventional way.
MH3 and MS3 are 100, 110 & 120 sizes
What do you expect from French company
Title: Re: Tire sizes, confused
Post by: Slakewell on September 02, 2014, 08:57:09 am
Bugger I wanted some S 12 for my little KX and went with Dunlops because I didnt think they made a small enough one.
Title: Re: Tire sizes, confused
Post by: Mick D on September 02, 2014, 10:32:33 am
A little off the track, but while close to the subject,
Not a hell of a lot of choice in Knobbies for rear 17" donuts,,,,,,,,

But got great surprise and ongoing feeling of satisfaction, with a
Kenda 130/90-17 K760 Trakmaster II DOT Approvd 20% Road 80% Dirt Dual Sport Tire
(http://i677.photobucket.com/albums/vv132/mc125mick/20140713_165826_zpsei9zljkw.jpg~original)

If anyone has found a better 17" rear Knobby
Or any ideas for a 17" dirt track rear ?? please share :)
Title: Re: Tire sizes, confused
Post by: OverTheHill on September 02, 2014, 10:46:29 am
371112319869 ebay number for a Barum 400-18 rear tyre for the older cz. fitted one to my triumph metisse over there in '67, then it rained--saved my day did that tyre, plus the fact that the stator was unraveling & made it missfire so bad that it got more power to the ground lol--well, was my theory anyway.
Title: Re: Tire sizes, confused
Post by: Mick D on September 02, 2014, 10:59:23 am
Yes, I thought they were ok on my 73 CZ400 too, Still have a new one in storage.
I wonder what their new Mitas ones are like??
Col Moody is a good fellow that has Been around the industry for years,
 I believe he is/or is attached to the Mitas importer?

PS; I am not going to a jab a sharp instrument at my stator to try your ignition theory ;D ;D
Title: Re: Tire sizes, confused
Post by: OverTheHill on September 02, 2014, 01:20:39 pm
yes, stator thing not recommended on a single cylinder or you'll be walking home lol. I had a spare cylinder so she was a 1.5 cylinder. Funny thing was it still barp bar barped its way around  christmas hills fast enough to pull endless wheelies & then get black flagged for it--or disqualified from the results of that race--was well in front in that one too, damn. Pissed down that day or i would have been totaly psyched out--hate dust.
Title: Re: Tire sizes, confused
Post by: OverTheHill on September 02, 2014, 01:33:24 pm
here's a tyre trick i'd never admit too--oh ok--neighbours kids chinese 150 thingy with a bald & flat 12 on the back & no money, fitted a bigger tube & folded it over which worked for ages but the damaged tyre internal cords were cutting through the tube in the end, so [always happens at the weekend when i can't escape], found a 12 pushbike tyre & tube so fitted that with the 300 12 over the top, forgetting it wouldn't blow up to 300 diameter inside it's own bike tyre. Must've put 120psi in before twigging, so let it down to 50 & it's still going 6 months later [worried now], doubled the suspension with a cushioning squash gap between tyres. 'don't tell anyone it was me'!!. Might be onto something there for the 4 & 7 inch suspension rule.