Modern Tire Sizes

[180pilot]

Can anyone tell me the new equivilant is to:

3.00-21-51R

4.00-18-64R

Need some new Metzlers on a 1981 R80GS

[dlearl476]

Google can:
http://www.dunlopmotorcycle.com/infocenter_tirecharts.asp

[MurphyPeoples]

I've found Avon RoadRiders to be great. Here's one website with prices:
http://www.tiresunlimited.com/ALL%20TIRES/AVON/AVON%20MC/avon_am26_roadrider.htm

Murph

[20774]

This will help to break down the inch-size dimensions:

http://www.mad-ducati.com/Technical/TireInfo/TireChart.html

Here's Metzeler's page:

http://www.metzelermoto.co.uk/web/default.page

The 4.00-18 should be pretty close to a 110/90-18...not that familiar with the cross-overs for a 21-inch wheel. Probably something like a 80/90-21... And that's a G/S, right? I have a hard time keeping the G/S and GS naming separate...

[lkchris]

There are none.

That's why these sizes are still available.

If a particular brand doesn't offer these sizes it means they don't offer sizes for Airheads requiring them.

In many cases it's USA distribution, as often a firm will indeed offer these sizes in Europe, where in some instances it's illegal to fit non-manfacturer-approved sizes.

Continental TKC-80 are a good example. They indeed produce 3.00X21 and 4.00X18 sizes but don't export them to the USA. I've imported mine from the UK.

Metzeler indeed produce these sizes, too. See http://www.metzelermoto.co.uk/web/catalog/moto/moto_catalogoDett.page?categoria=/catalog/moto/enduro_street&vehicleType=MOTO&menu_item=/products/catalog/enduro_street

IMHO Airhead riders should support tire manufacturers that support them.

And, forget the word "modern." It's not applicable and just confuses the issue.