I'd think a more thorough description of the speedometer problem might be necessary to evaluate the likelihood of repair from the kit linked.
The most common cause of KLR speedometer malfunction (IMHO) is, bent "ears" on the winged washer (RECEIVER-SPEEDOMETER 41064-1051) in the hub, failing to engage the corresponding slots in the hub (the bending a result of improper reassembly of front wheel and axle after removal). The repair: Flatten the wings (with vise, and/or hammer and flat hard surface), re-assemble with ears in slots.
Beyond this common malfunction/repair, a lot depends upon the speedometer drive (does the speedometer cable turn when the wheel rotates?), and the speedometer instrument itself (when the speedometer cable shaft is chucked in an electric drill, and the drill chuck rotated counter-clockwise, do the odometer and speedometer needle register anything?). If the problem's in the hub, the kit may or may not fix it; impossible to predict without further examination, IMHO.
BTW; pictures would help diagnosis; you need 15 posts before the website judges you worthy of posting images!
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