ENGINE REPAIR

14. To calculate the gear ratio, divide the number of teeth on gear G by the number on D. Divide the number on gear E by the number on gear F. Multiply the two together to the fourth gear ratio.
15. The foot shift lever is pulled up to engage sliding dog, K, disengages from gear D and engages gear E (see Figure 17).  Gear the main shaft, so power flows . There is no gear reduction in gear.  The ratio is 1: 1 in all Ossa transmissions.

TRANSMISSION INSPECTION

1. Clean all parts thoroughly in solvent and dry compressed air.
2. Carefully check all parts for wear or damage.
3. If a thrust or friction surface shows a blue it means the part has suffered from excessive heat.  Replace it.
4. Check the teeth on all gears for wear or damage.  If the gear shows any wear, the opposite gear probably has been damaged by meshing with it.
5. Check the engaging dogs of all gears and the fourth and fifth gear sliding dogs.  If any of the dogs have rounded edges, replace them.
6. Check the freedom of the sliding gears to move back and forth on their shafts, along with the engaging dog.  Be sure there is no binding on the shaft.
7. In the case of broken teeth on gears or a foreign object in the transmission causing it to seize, check the main shaft and lay shaft for straightness.
8. Put the shaft in a set of machinist's centers (see Figure 18) fitted with one dial indicator.  Put the dial indicator on the middle of the shaft and rotate it slowly.  If it shows a run out of more than .001", replace it.
9. Carefully check all bearings and bushings in a transmission with broken teeth or with a seizure.  Replace any doubtful part.

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