Tire Size Changing- 1980 GS850

[Poot]

Hi all,


I'm going to be switching the front tire on my 850 from a 110/90 to a 100/90, based on someones advice.

I'm wondering if there is a possible change/upgrade for the back tire choice from the 130, maybe to a 120?


Would this increase the handling? I'm running with progressive suspnsion front and rear, and am also shortening the spacer in the front during the winter for some better cornering, and am looking to make this bus handle as well as it possibly could.

thanks.



POOT

[KGB]

Going down in a size, as in ur case shouldn't be aproblem.
If anything it will make it handle a little quicker or turn in quicker.
Also depending on brand and profile of tire.

You may want to keep the 130 rear if your doing lots of high speed highway, more contact patch, and if you carry a load.

[Poot]

ok. sounds like a plan. I do a fair bit of high speed, bot with and w/o load.

I'm doing my road trip now, which should mean that my tires (me88) will last till the end of the season. I'm then going to put the 55 on the rear, and if the front is no good after this season, then I'll change it to the 100/90. Its still good, as it was brand new at the beginning of last season. no weird spots, bubbles, etc.


thanks.



POOT

[bwringer]

The standard and best handling tire size for an 850 is 100/90-19 front and 130/90-17 (130/90-16 for a GL model) rear.

Some claim that 110/90 fronts don't affect the handling. I happen to know for a firsthand fact that a 110/90 front does affect the handling negatively, turning a very nimble bike into a pig, relatively speaking. You won't crash and die, but the bike is not as nice to ride. Stick with the 100/90-19.

Some also claim that you can sometimes cram a 140/80 rear in a shaftie, depending on the tire brand. I haven't tried this personally, but I do know the rim width is too narrow for the wider tire, so the tire profile will be wrong and the effect on handling will also be negative. Stick with the 130/90-17 (or 16).

The equivalents in letter size tires (Dunlop 491) are MM90-19 and MT90-17.

[Grandpa]

The standard and best handling tire size for an 850 is 100/90-19 front and 130/90-17 (130/90-16 for a GL model) rear.

Some claim that 110/90 fronts don't affect the handling. I happen to know for a firsthand fact that a 110/90 front does affect the handling negatively, turning a very nimble bike into a pig, relatively speaking. You won't crash and die, but the bike is not as nice to ride. Stick with the 100/90-19.

Some also claim that you can sometimes cram a 140/80 rear in a shaftie, depending on the tire brand. I haven't tried this personally, but I do know the rim width is too narrow for the wider tire, so the tire profile will be wrong and the effect on handling will also be negative. Stick with the 130/90-17 (or 16).

The equivalents in letter size tires (Dunlop 491) are MM90-19 and MT90-17.

I totally disagree with you, bwringer, probably for the first time I can remember. I had four 850's, from 1986 thru 1999, and ran 110's on them. I tried a 100 once and couldn't tell the difference in handling. I agree that a 100 wouldn't hurt, though...

I have a 110 on the front of the GK I presently ride. I recommend to all that you use a 110 if you have any kind of frame-mounted fairing and/or are a heavy rider and/or push it hard on the corners (all three apply to my case).

I have a friend who installed a 140 on the rear of his GK, and it was sooooooo... tight with the swingarm back there, I'd hesitate to intall one. I agree tht a 130/90-17 (or 16) is best for the back.

[awjonesii]

I originally had a 100/90/19 on my front tire. I ride an 82 GS850. The shop I bought my tires at put a 110/90/19 on it when I had them replaced. I thought it was a bit heavy but overall happy. Until...I bought new tires recently and to the suggestion of a friend - put the correct 100/90/19 back on - my goodness, what had to be pushed into a corner hard, now slides in and out alot faster and smoother.

I recommend the 100. Do what you want, but I would swear by it as far as handling goes.