GSXR front end speedo
 

I'm going to fit the speedo to my front end (K3 GSXR) I have fitted aftermarket discs (10 bobbins) which means i can't do the old magnets in the holes trick.

I was planning to stick the magnets to the disc and need to make sure the speedo is going to be accurate. Anyone know if there is a set distance the magnets need to be fron the axle in order for it to be accurate? I could always mount them wherethey would go on standard discs providing they will fir there.

Any ideas gratefully appreciated!