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  4. KSS, KTS Manuals
  5. F236/4R Mk. II OHC Instruction Book 1950
  6. Refitting the Main Bearings

NOTE SPECIALLY that the inner rings of the main bearings taper .001-in. per inch and must therefore be fitted the correct way round to their respective shafts. The "large" ends of the inner rings are always fitted adjacent to the Flywheel bosses, i.e., they are placed on the shafts "large end first."

The "large" ends will be found on inspection to have a pronounced radius, but as an extra check, "Hoffman" bearings have the maker's name and identification serial numbers stamped on the opposite side of the races so that when correctly fitted these marks should be outside and remote from the flywheels.

Should an attempt be made to fit the bearings the wrong way round it will be found that they will hardly go on to the mainshafts at all when pressed lightly into position with the fingers.

Heat the Crankcase halves before fitting the timing side ballrace or the outer ring of the roller race by immersing each half in boiling water until it is hot enough to allow the bearing and the outer ring to be dropped into the housings.

Before fitting the ballrace fit the oil retaining shim (K150) and any shims for taking up end float, but always fit the oil retainer next to the ballrace. No other shims must be fitted between the bearing and the oil retaining shim.

See that the outer ring of the roller race is fitted with lip at the bottom of the housing, otherwise it will be impossible to slide the Crankcase into place owing to the rollers being unable to enter the outer ring.

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  • Velocette Documents
    • GTP Manuals
      • F40/5R GTP Instruction Book 1951
    • KSS, KTS Manuals
      • F236/4R Mk. II OHC Instruction Book 1950
      • F42/3R OHC Models 1925-1931 Instruction Book
    • MAC Manuals
      • F469/4R MAC Service Guide 1965
      • F466/2R MAC Owner's Handbook 1955
      • F50/7R MAC Rigid Frame Service Manual 1955
      • F50/4R Supplement
    • MOV and MAC
      • F131-3R Instruction Book 1937
    • MSS Manuals
      • F477 Owners Handbook 1954
    • Venom, Viper, MSS
      • F485/1R Owner's Handbook 1956
      • F484/9R Service Guide 1967
      • F484/11R Service Guide 1971
    • Valiant Manuals
      • F62-1R Service Manual