Correct Front tire size for xs650 Standard with 1.85x 19" Rim?

[XS650D]

I purchased 2 new Avon Roadrider tires for my 77 Standard.The current front tire I have
on my bike (what I purchased bike with) is 100/90-19.
When I ordered the tires they said its suppose to have a 3.25-19" front tire on that rime size.
Apparently the 100/90-19 is 1/2" wider and 1/4" taller. Can I get any advise on this before placing order.
Thx

 

[TwoManyXS1Bs]

The older manuals call for a 3.50-19", for the same 1.85x19" rim.
Don't know why later manuals show 3.25".
Maybe an "ease of clearancing" the caliper during wheel servicing?

 

[XS650D]

Not sure what size 3.5 works out toadies that mean the wider 100/90-19 will be fine?
Or should I get the 3.25-19 Thx TwoMany

 

[TwoManyXS1Bs]

By the strict math conversion,
3.25 would be an 80,
3.50 would be a 90.
A lot of folks run the 100/90 just fine.

The "actual", measured tire dims of P-Metrics freaks me out. They're all over the place. Some discussion in here:

http://www.xs650.com/threads/center-stand-technique.44774/

 

[fredintoon]

Not sure what size 3.5 works out toadies that mean the wider 100/90-19 will be fine?
Or should I get the 3.25-19 Thx TwoMany

Hi XS650D,
nah, 3.25-19 has been considered too skinny for a 650cc bike since the 1970s.
3.5" = 88.9 (call it 90)mm.
As inch-sized tires are 100% (height = width) a 3.5"-19 tire will have the same outside diameter as a 100/90-19 tire although the metric tire will be wider.
My own '84 Heritage Special has been running on 100/90-19 fronts ever since it's original tire wore out.
One time my son mis-remembered the tire size and bought a 110/90-19 for his 1980 Special.
It fit the rim and held the road OK but there was only perhaps a millimeter clearance between it and the front fender.

 

[XS650D]

Sounds like the 3.25-19 is the way to go,Atleast I know it will fit as thats the size I have on it now
and no problems that I am aware off.I emailed Avon direct and they stated that the 3.25 was the correct
size based on the rim being 1.85" Whats the down side to running the 3.25" (1/2" Narrower and 1/4" shorter than the 100/90)
Has anyone tried both on the front and noticed any difference.I think 5Twind mentioned in a previous post that going with a
wider rear tire really slowed down the turn in and he did not like it.No mention of front tire issues with sizes though.
I had a Sportster Custom with a 21" front very skinny stock tire and it would literally slip across greasy sections of the road
when pushed hard into a corner fast, very nerve racking.I think a slightly wider tire on the front of that bike may have
helped with more skin on the pavement!

 

[5twins]

I've always used the 100 size on my '78 Standard. I've had several different brands and tread patterns, all fit fine and for the most part, worked well. I say for the most part because I'm really not crazy about my current tire, a Shinko 712. It just feels "vague" and squirmy at certain speeds. I can't wait to wear it out so I can change to something else, lol.

 

[fredintoon]

I've always used the 100 size on my '78 Standard. I've had several different brands and tread patterns, all fit fine and for the most part, worked well. I say for the most part because I'm really not crazy about my current tire, a Shinko 712. It just feels "vague" and squirmy at certain speeds. I can't wait to wear it out so I can change to something else, lol.

Hi 5T,
don't wait until that squirmy Shinko endangers your well-being, swap it out right now while there's still a legal amount of tread on it and you can sell it on.
Sell it to a sidecar man.
While I'm on the paranoid side of fussy about solo tires the rules change for sidecars.
There's only two.
Will it hold air?
Is there still any tread showing?