Speedo ratio for the dohc 250 special (19" wheel)

[rickee]

Hiya,

Does anyone know the speedo ratio for the dohc XS250 special, it has the 19" wheel with curved spokes same as the 400 maxim. I'm building a lean and clean cafe for the wife so I'm going with a mini speedo.

Thanks in advance!

Richard

 

[drewpy]

thought it was 18" wheel!

 

[rickee]

Nope, Some Maxims have 19, certainly the XJ750, DOHC XS250 special and XS400k Maxim have 19s with a 16 inch rear end. Real fat rear so it works out to be a similar rolling radius to a 17" I was thinking of trying to get hold of a set of 18s for the wife's bike but a: Too much money and b: The extra height in the rear might get in the way of the plan for an underseat exhaust and c: too much money.

But it does make buying a speedo problematical as I don't know the ratio.

 

[XSLeo]

With the cable off the speedo drive put a match stick with a small flag made from tape. Now with the wheel off the ground turn the wheel one revolution, count how many times the match stick turns.
Now turn the wheel counting how many times the wheel turns to get one revotution of the match stick.
One of them is the drive ratio.
Leo

 

[drewpy]

With the cable off the speedo drive put a match stick with a small flag made from tape. Now with the wheel off the ground turn the wheel one revolution, count how many times the match stick turns.
Now turn the wheel counting how many times the wheel turns to get one revotution of the match stick.
One of them is the drive ratio.
Leo

reminds me of this

this is where I live BTW