Tyre Size Confusion - Is there guaranteed right info somewhere?

[pete]

So I've seen mixed information all over the shop as to what tyre sizes I can safely run on my '82 450E.

I know the stock tyres are 3.00-18 (F) and 3.50-18 (R).

Front rim is 1.60" and rear is 1.85".

Currently on the front I have a dodgy old Michelin that's hard as a rock and is 90/90-18, and I've got a dodgy bald in the centre Barracuda on the rear that's a 4.10-18.

So, I know on the front I can run 90/90-18 and 3.00-18 safely, and I know on the rear I can run 3.50-18 and 4.10-18 safely.

So, what other sizes can I safely run on those rims? 3.50-18 on the front? 100/80-18 maybe?

Basically I'm having trouble finding some road biased dual sports to suit my scrambler...

Any input would be helpful right now as my head is just a blur of tyres sizes and types...

[BassCliff]

Hi,

You do get a little wiggle room for tire sizes, being that there are now different sizing standards with modern tires. The closest sizes to stock for your bike would be 100/90 for the front and 110/90 (or maybe a 120/90) for the rear. There are sizing and conversion charts on my little website and all over the interweb if you'd like to research more.


Thank you for your indulgence,

BassCliff

[Nessism]

Those are pretty skinny wheels. I'd try to keep to a 3.25 or 100 front as the max size, and 110 max on the rear. Off road tires tend to use narrow wheels so that may work in your favor.

[pete]

Hi,

You do get a little wiggle room for tire sizes, being that there are now different sizing standards with modern tires. The closest sizes to stock for your bike would be 100/90 for the front and 110/90 (or maybe a 120/90) for the rear. There are sizing and conversion charts on my little website and all over the interweb if you'd like to research more.


Thank you for your indulgence,

BassCliff

Thanks BassCliff, the conversion from the old to new sizing is where I get lost, and my searching of the interweb is what's led to my confusion as there are many conflicting results.

I even saw one result that said the 3.00-18 is too wide

Those are pretty skinny wheels. I'd try to keep to a 3.25 or 100 front as the max size, and 110 max on the rear. Off road tires tend to use narrow wheels so that may work in your favor.

Thanks too Ed, I actually thought I wouldn't be able to go bigger than a 90 up front, but I believe 100/90 will actually make things a little easier, if not 3.25.

Thanks heaps guys, I really want to try to get the dual sports on, but at the same time I don't want to compromise my safety on the road just for looks, I'd really prefer the looks to be the compromise if it comes to that...