Yamaha RD specs- | *These are aircooled models. | |||||
RD125 | RD200 | RD250 | RD350 A/B | RD400 | ||
Pist. Side Clearance (in.) | .0014-.0016 | .0016-.0018 | .0016-.0018 | .0016-.0018 | .0012-.0014 | |
Ring End Gap (in.) | 0.008-0.016 | 0.006-0.014 | 0.006-0.014 | 0.008-0.016 | 0.012-0.020 | |
Oil Pump-Min stroke (mm) | 0.20-0.25 | 0.20-0.25 | 0.20-0.25 | 0.20-0.25 | 0.20-0.25 | |
Compresion Ratio | 7.1:1 | N/A | 6.6:1 | 6.6:1 | 6.2:1 | |
BoreXStroke (mm) | 52x46 | N/A | 54x54 | 64x54 | 64x62 | |
Weight (stock)-LBS | 256 . | N/A | 309 . | 315 . | 342 . | |
Carb Type | Tekiei-Y20P-1A | N/A | Mik- VM28SC | Mik- VM28SC | Mik- VM28SC | |
Main Jet | 94 . | 94 . | 120 . | 140 ('75 =110) | 115 . | |
Pilot Jet | 44 . | 44 . | 30 . | 25 . | 25 . | |
Float Level (mm) | 20 | 20 | 15 | 15 . | 23 | |
Jet Needle | 4D50-2 | 4F51-2 | 514-3 | 514-3 | 5L1-3 | |
Needle Jet | N30 | N80 | O-8 | O-8 | P-2 | |
Air Screw Turns out | 1 1/2 | 1 1/4 | 1 1/4 | 1 3/4 | 1 1/2 | |
Point Gap (mm) | 0.30-0.40 | 0.30-0.40 | 0.30-0.40 | 0.30-0.40 | 0.30-0.40 | |
Spark Plug -NGK # | B8HS | B8HS | B9HS | B9HS | B8ES | |
Plug Gap (mm) | 0.6-0.7 | 0.6-0.7 | 0.5-0.6 | 0.5-0.6 | 0.6-0.7 | |
Timing- @mm BTDC | 1.8 | 1.8 | 2 | 2 | 2.3 | |
Transmisson Ratios: | ||||||
First | 2.833 | N/A | 2.571 | 2.571 | 2.571 | |
Second | 1.705 | N/A | 1.777 | 1.777 | 1.777 | |
Third | 1,250 | N/A | 1.318 | 1.318 | 1.318 | |
Fourth | 1.045 | N/A | 1.04 | 1.04 | 1.083 | |
Fifth | 0.916 | N/A | 0.888 | 0.888 | 0.961 | |
Sixth | N/A | N/A | 0.785 | 0.785 | 0.888 | |