145/80-13" tires

[GasSavers_Ryland]

I'm thinking that the next time I need to get tires I should really get some 145/80-13" tires, but they seem like they might be as hard to find in the US as the 165/70-13" that came stock on the VX, altho I did find a set of 5 snow tires in that 145/80 size on Ebay, of course they are snow tires... anyone looking for some super narrow snow tires?

[budomove]

The kumho 795 all season comes in 155/80, is lrr, 14lbs, rated among the best in all seasons for snow, ranks near the top in survey results across the board, and costs $30 from tirerack. I have a set of these in the mail for my hx rims in 175/65/14 and they are 14 lbs, 1lb more than the re92 in 165/65/14, half the cost, and twice the expected treadlife

Xfi was also considering these for either his vx rims.

http://www.tirerack.com/tires/Compar...t=All&x=10&y=8


edit: If you read the reviews, you will see they handle great on wet, are really quiet, wear very slowly, AND people comment on better MPG.

[budomove]

anyone know if revs per mile on a tire affects mpg?
I would assume there'd be a direct link between diameter and revs per mile, but apparently there isn't. a 175/65/14 potenza with a diameter of 30" has a 906 revs per mile, whereas a 175/65/14 kumho 795 with a 29.? diameter has 880 revs per mile. how is this possible?

[LxMike]

Originally Posted by budomove

anyone know if revs per mile on a tire affects mpg?
I would assume there'd be a direct link between diameter and rpm, but apparently there isn't. a 175/65/14 potenza with a diameter of 30" has a 906 rpm, whereas a 175/65/14 kumho 795 with a 29.? diameter has 880 rpm. how is this possible?

yes it does. more rev per mile means your engine will be turning faster also. your speedo would be off too.

[budomove]

By rpm, I meant revs per mile, and I understand the link b/w revs/mile and odometer.

If you compare the specs, you will see diameter and stated revs per mile don't jive. there must be another variable in determining revs per mile. the kumho diameter is between the two re92 diameters, and so should its rpm if it were a causal relationship.

kumho 795:

175/65 SR14 (lrr, 14lbs)

22.9"
880

re92:

165/65/r14 (lrr, 13lbs)
22.5"
926

175/65 SR14
23"
906

[LxMike]

there gonna be a varience between tires even same sizes will measure slightly different. also would depend on what tire pressure they was measured at

[budomove]

max pressure:

kumho 795:35psi

potenza re92:44psi

So if psi effects revs per mile, and revs/mile affect odometer reading, that means that even people with the right tires for their odometers are getting false mpg info. Does the same go for SG and SuperMID?

Are we all touting our mpg horns with inaccurate info?!

There is a formula to figure out actual mileage, but most people i assume don't do this, and if they do it doesn't take into mind the effect of tire pressure on revs per mile, which is big if that is the main diff in re92/kumho 795 revs per mile readings.

[QDM]

It's easy to check the accuracy of a spedometer/odometer/tripometer by using a GPS. My motorcycle is right on, my Swift reads 5% under, and my Toyota pickup reads 5% over.

Q

[GasSavers_Ryland]

revs per mile could also change if you have a soft side wall compared to a stiff side wall, but you would also want to know total diamiter to make sure that you are not going to have tires rubbing on fenders, if you mesure the distance between the center of your wheel hub, and the groud, and the center of the hub, and the top of the tire, you'll notice that your tire is soft, and that affects how many rotations per mile you get.

I'm still wondering about the 145/80-13 tires, contenetal is suposed to make one in that size, or they used to, that was advertized as an Eco tire with LRR properties, but I can't find it now, and am not sure if they even sell it in the US

[GasSavers_DaX]

My N600 uses 145-80's, but they're R10's. Kumho Power Star 758's. Very skinny.