Transmission Assembly - Yamaha JT1 Series Service Manual

ENGINE-
Cr,ankcase, Transmission Assembly
Fig. 3-15-5 Fig. 3-15-6
Note:
Fully tighten' the bolts of the crankcase dividing tool. keeping the tool in a horizontal position.
The crankcase is designed to split into two halves. right and left. Only one drain plug is provided for both the
transmission and clutch housings. Both housings can be drained at the same time by removing the drain plug.
8. Reassembling
a) When reassembling the crankcase, be sure to apply
YAMAHA BOND No. 5 to the mating surfaces of
both halves after cleaning them thoroughly.
3-16 Transmission Assembly
Fig. 3-15-7
The constant mesh, wide ratio. 4-speed transmission makes it possible to fully utilize the steady performance of the
engine throughout the entire speed range from low to high speed.
For layout of the transmission and related parts, refer to Fig. 3-16-1 and 2. The primary reduction ratio is 74/19 =
3. 894. Therefore the total reduction ratios will be; Primary reduction ratioxTransmission gear reduction x Secondary
reduction ratio= Total reduction radio.
~
Primary _Reduction Ratio ........................... 74/19 =3.894
Secondary Reduction Ratio .....................• 41 /13 =3.153
Transmission Gear Reduction Ratio Total Reduction Ratio
1st 40/13 =3.077 37. 773
2nd 34/18 =1.889 23.193
3rd 30/23 =1.304 16.010
4th 27 /26 =1. 038 12.188
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