18” rear wheel mag

[Yourstrulythom]

I have an 18” rear disc mag from a 79 sportster that I would like to mount on my 99 sportster. The wheel is 18” x 2.5” I have read that people have done this without much difficulty. Some spacers are all that seem to be required. Does anybody have any experience with this or happen to know what size spacers will be needed to make this work? Thanks in advance for any info you have.

The bike is currently running the stock 16” x 3” rear wheel
The bike is running a chain and not a belt.
Sprocket on the rear wheel is flat and not dished (PBI 2073-53-HD)
Sprocket on the transmission is .500” offset (PBI 283-23)

[Racepres]

Go for it, check and Double check yer Spacing...especially at Brake rotor/Caliper, Interface.... But... I wonder exactly What you believe you will Gain????

[45Brit]

The same as the MoCo expected to achieve by fitting it to the CR?

Not so many years ago I’d have preferred an 18” to the 16” on my XL, but with modern tyres I think it’s much less important than previously.

[gadsdenxls]

I've had 18" Harley cast wheels on a '91 Hugger and a '96 XLS with stock sprocket/pulleys on the tranny. They both used a .300" spacer on the wheel sprocket/pulley side to line up. Having a .500 offset on your tranny sprocket will change that.
IIRC, the axle spacer on the brake side was 3/4".
Hope this helps.