| Diagram | Fig. 23 — REAR WHEEL — USE WITH SMITHS SPEEDO DRIVE BOX R/H SIDE · ref 26 |
| Subsystem | wheels |
| Listed in parts books | 1979–1980, 1985 |
Sprocket 45 tooth - As reqd
45 tooth rear wheel sprocket for the final drive chain, part number 37-7072.
This is the 45 tooth rear wheel sprocket, part number 37-7072, sometimes seen under the alt number W7072. It bolts to the rear wheel hub and is the receiving end of the final drive chain, doing the work of stepping down the gearbox output into rear wheel speed.
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The catalog record shows this part appearing alongside both Smiths and Veglia speedo drive box setups, with separate rear wheel entries noting right-hand and left-hand side speedo drive placement. That tells you the rear wheel assembly on these bikes was built around whichever speedo drive gearbox was fitted, so when you're sourcing a replacement sprocket it pays to know which speedo drive arrangement your hub carries.
Our listings for this part span 1979 to 1985 in the catalog. If you're not sure whether your rear hub takes this 45 tooth sprocket versus a different tooth count, give us a call before you order and we can confirm fitment against your bike.
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