tire size

[dealjb]

Anyone running 130 rear on 80 GS1100E? Have 4.50 (120) on it now. Looks like it might be tight on the chain guard side.
Thanks

[GSJohn]

Duane is right on....here is a site that gives the dimensions for various sized tires. The diameter difference between a 120/90 and a 130/90 is 0.71 inches.

http://victorylibrary.com/tech/tire.htm

[robertrafal]

anybody notice a difference in the front wheel size of an 1981 gs 850g and a 1982 gs 850g? Is the latter wider? the wheel, not the tire of course.

[psyguy]

anybody notice a difference in the front wheel size of an 1981 gs 850g and a 1982 gs 850g? Is the latter wider? the wheel, not the tire of course.

suzuki did play with the rim sizes on 850's around that time, remember reading about in the service manual

[TheCafeKid]

suzuki did play with the rim sizes on 850's around that time, remember reading about in the service manual

Yes. Both front and rear are different widths. I cant remember how much, but its slight. My 82 1100G STOCK came with a 130/90-17 in back and a 100/80-19 in front. I currently have a set of 81 850 wheels on it, cos i like the star pattern better, (in 82 the rim styles changed as well) and its sitting on 110/80-19 and 130/80-17s. So i dont think the difference would matter in tire size. However, you may be more likely to get away with a 140 in back on the newer rim without pinch if you so desired.

[psyguy]

I currently have a set of 81 850 wheels on it ... and its sitting on 110/80-19 and 130/80-17s.

hm, i'd double check that those are the correct sizes for an 81
the profile should be 90 not 80 for a good fit on the rim, iirc

[TheCafeKid]

hm, i'd double check that those are the correct sizes for an 81
the profile should be 90 not 80 for a good fit on the rim, iirc

Im not a tire expert, but I was assuming that the profile wasnt as important as the width, seeing as the profile seems more to do with the hight of the tire itself more than anything. For instance, if you were to change from an 18 inch rear to a 17, the hight loss in the rim could be made up, mostly, in the profile. Personally, *I* notice the difference in ride hight from 80 to 90, and its only a half inch all the way around. Most concern in tire size seems to come from the width, that you dont go too wide that you pinch, thereby eliminating the larger contact patch you were trying to achieve with a wider tire anyway. Am I wrong? Can you shed more light on this for me?

[psyguy]

excuse me if i'm not clear in my explanation...

Can you shed more light on this for me?

a lower profile tyre will be more "squeezed" to fit the rim (relatively to a higher profile tyre of the same width)
as 130 tyre is already at the top end of what you can fit in terms of width for that rim width (tyre/frame clearance issues aside), changing to the lower profile is going to:
1. make the tyre thread portion flex more than what it's designed for - thus negatively influencing the rideability,
2. put more pressure on the tyre sidewalls - thus negatively influencing the rideability

btw, 130/90 vs 130/80 = 13mm sidewall size difference and no width difference BUT when put next to each other on the same rim 130/90 apears noticeably wider than 130/80

[TheCafeKid]

a lower profile tyre will be more "squeezed" to fit the rim (relatively to a higher profile tyre of the same width)
as 130 tyre is already at the top end of what you can fit in terms of width for that rim width (tyre/frame clearance issues aside), changing to the lower profile is going to:
1. make the tyre thread portion flex more than what it's designed for - thus negatively influencing the rideability,
2. put more pressure on the tyre sidewalls - thus negatively influencing the rideability

btw, 130/90 vs 130/80 = 13mm sidewall size difference and no width difference BUT when put next to each other on the same rim 130/90 apears noticeably wider than 130/80

Right ok i see what you are saying now. Basicly the same width tire, but one with a lower profile will not have the advantage of the hight of the other, therefore its a greater angle from the bead to the edge of the tread, increasing the amount of stress on the sidewall. The 90 would be a bit more vertical, allowing more linear displacement of the stress. Gotcha. So is it possible to run a 140 on one of the 82 and up rims without serious interference or pinch? Anyone done this?

[TheCafeKid]

BTW psy, what pipe is that on Bruno? Its pretty slick, id like to find one like that for the cafe.

[Suzuki mad]

GS1000E 130/90/17 pirelli sports demon.

GS(X)1100E 130/90/17 Battlax BT45.

No problems.

Suzuki mad

[psyguy]

tck, yes, you got what i meant... and explained it in more technical terms, too :-)

the pipe was made locally, it's for sale actually, but the shipping would be a killer

[Grandpa]

So is it possible to run a 140 on one of the 82 and up rims without serious interference or pinch? Anyone done this?

I ran a 140/90-16 on the rear of my (your) GK once, with no adverse effect. It was a HiMax C.S.

When you get it, it will have a 130/90-16 on the rear, on the stock rim. I'll give you the 17-inch old-style rim with it.

[snark]

Here is a tire conversion chart I've found.

http://www.steelthundercc.com/tiresizes.html

BTW I just put a set of Pirelli MT66's on my 450L. I rode them to Johnstown this week for Thunder in the Valley in the rain...they stick like glue.

[catbed]

here's another one:

http://www.webbikeworld.com/Motorcycle-tires/tire-data.htm