Tire size conversion?

[DMB]

My bike ('80 GS550E) takes 3.25H19-4PR front and 3.75H17-4PR rear tires. How do I convert those sizes into the current sizing standards.

I would like to know how to convert them so just telling me the size I need is good but not really what I am looking for.

Thanks.

[BassCliff]

HI Mr. DMB,

There are many tire conversion charts all over the web. You can search for one or just use the one I "borrowed" for my website.

http://members.dslextreme.com/users/bikecliff/images/tire_info.html

Thank you for your indulgence,

BassCliff

[DMB]

Awesome. Thanks. I never scrolled down that far on that page.

[Nessism]

Those tire sizes are listed in inches. Convert to mm by multiplying by 25.4 if you an want exact conversion.

3.25 = 82.55mm

3.75 = 95.25mm

Understand that in the real world the tire sizes typically don't match the stated dimensions.

[DMB]

Those tire sizes are listed in inches. Convert to mm by multiplying by 25.4 if you an want exact conversion.

3.25 = 82.55mm

3.75 = 95.25mm

Understand that in the real world the tire sizes typically don't match the stated dimensions.

So if I look at that than I would want to get a 80mm width front tire and a 90 or 100 mm wide rear tire? But according to the chart I should get a 90 mm wide front tire? Is it not that big of a difference to matter?

[Nessism]

As stated before, the listed width is not always the actual width. The modern equivalent sizes to the actual tires would be 90/90-19 front and 110/90-18 rear. Honestly, forgive me for saying but I think you are over thinking things. Suzuki changed tire widths from year to year on many models without changing the rims so why get all bogged down with trying to match the exact width that came on your bike? The front rim is 1.85" wide, just like most GS bikes, and 2.15" rear. Most GS bike owners run a 100 front so that one is easy. The larger front tire helps correct the speedo error so that's a bonus. For the rear, a 120/90 matches the rim width nicely and matches the bike as well. I run those sizes on my 550E and they match the bike perfectly.

Good luck.

[psyguy]

another route

rim size (incl rim width) is stamped on the wheel
tyre manufacturers have charts that tell you what tyre size to use on what size rim
usually more than one tyre size fits a particular size rim

best follow tyre manufacturer's recommendations