how much fudge room on tire size??

[snowbeard]

well, I at least know I'm not gonna get a 16" or and 18" on my 17" rim , but if my original tires (well, what's on it now anyway) were 130/90 17, how much can I push the 130? I've got an '81 GS650G, shaft, full on stock everything.

I don't suppose I want to go smaller either, unless someone can give me a REALLY good reason...

and while I've got ya's, what exactly is bias in a tire? can I still get a radial biased tire on there? excuse the newbie ignorance

Thanks all!!


edit:I realize I may have ignored some numbers on my tires, but I am not near the bike to remember exactly... but anyone who knows what they're talking about probably can fill in the blanks?

[Joe Nardy]

Snow,

You could probably go up to a 140/90 but there really isn't any reason to change from stock. A wider tire will make your bike turn more slowly. You can also end up with a SMALLER contact patch due to the wider tire being pinched onto a too narrow rim. I'm not familiar with the shaft bikes but you might also have clearance problems between the tire and shaft.

Bias and radial refer to the direction the belts inside the tire are oriented. A radial pattern makes the tire more flexible and therefore gives a better ride and better handling. You probably will not find any radial tires in the sizes to fit your bike. Radials came along after our bikes were being produced and are made in the wider sizes to fit the later bikes. There are many posts on this site regarding tire preferences. You will most likely be happy with Metzelers, Dunlops, Pirellis, or Bridgestones.

Thanks,
Joe

[snowbeard]

thanks, I've definitely got a good feel for what tire to get, but now I'm running into availability problems, 17" just isn't a preferred size it seems... so I'm trying to get my range on what works when I'm surfing ebay!!

nice point on the turning radius, maybe I will hold out for 130 after all!

[first timer]

on my 81 550 which should be very similar to your 650 i can only go to a 130 then i have about .25" to .5" before the tire rubs on the brake arm. there isn't much need to go bigger then 130. these bikes were designed for even narrower tires then this. you shouldn't have much problems finding a 130 tire espesially a metzler. ebay you stand a chance of buying a old driedout tire.

ryan

[snowbeard]

yeah, I am slightly worried about that with ebay, I guess I'll have to be really careful.

[mtngoat]

Re: Tire sizes..

I recommend you read the specification label on your bike's spindle housing. The label describes the rim and tire sizes for your model.

Then go to any motorcycle supplyhouse on the WEB. Many of them have a "tire fitment guide" which will give you the tire sizes available for your bike.

Motorcycle Accessory Warehouse and Discount Motorcycle Tire both carry a fairly good range of tires. Their prices aren't bad either..

Good luck,

Herb
(mtngoat)

[Anonymous]

I to was looking for a tire for my 80 GS850 and I ended up going with a stock tire size cuase of the clearences. i ended up getting mine from Dennis Kirk. www.denniskirk.com. They were the only ones that I could find the same size. 120/90 I think was the size. gave about $80.00 for the rear.

[Dink]

Tyre construction is fairly simple!
Radial= the belts run "radially around the tyre.
Bias= the belts are "biased at an angle to the rotation to the tyre.

I think sticking close to stock in tyre sizes is the best way, one size over is generally all that will fit and clearences are tighter on shaft driven bikes.
Dink

[Anonymous]

Is it physically harder to put a wider tire on a specific rim? I just switched to my summer rear time and nearly blew a gasket getting the second bead on without interfering with the tube. Stock is a 3.5x18 and I run a tubeless 110/90 instead. It seems to me that the tire is squashed really flat and there is no room for the inner tube until you air it up to push the beads apart. I find that I need to pump the tire up over 50 psi to get that last bit of the bead to seat too, I'm not sure how much more than 50 since my guage goes out of range.

That's my take anyway, Steve

[mcycle-nut]

Bias= the belts are "biased at an angle to the rotation to the tyre.

Dink

You mean it has nothing to do with what one thinks of a certain tire, as in "Metzelers are best, f#$k the rest?

[Dink]

Bias= the belts are "biased at an angle to the rotation to the tyre.

Dink

You mean it has nothing to do with what one thinks of a certain tire, as in "Metzelers are best, f#$k the rest?

8O I know incredible aint it!!! 8O
Dink