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Splash Fed Big End Bearings

Discussion in 'The Garage' started by ogrilp400, Oct 30, 2011.

  1. ogrilp400

    ogrilp400 XS650 New Member

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    I have just been informed that XS 650s' have splash fed big end bearings. Is this correct? I thought splash fed big ends went out with 1940s stationary engines.
     
  2. gggGary

    gggGary Old guy, NO expert.

    The engine has ball big end bearings and contains oil passages and ports to ensure needed oil keeps the bearings lubricated. Ball and roller bearings do not need a high pressure oil film to live like babbit type bearings do. Bearing failure in XS650s tends to be related to disuse allowing rust to form rather than wear during use. With reasonable oil changes the bottom end often goes 60,000 miles or more between overhauls.
    The manual shows a lubrication schematic and I swear i have seen engine oil distribution art also but can't place my finger on it. So... who was the expert who "informed" you that it's splash?
     
  3. ogrilp400

    ogrilp400 XS650 New Member

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    I was discussing oils, pumps and bearings on another bike forum and a bloke there said "XS 650 big ends survive on a splash feed oil system" I find this hard to believe. I have had very very little to do with Japanese bikes but do believe that they would have a gear pump pumping oil into the crank shaft.
     
  4. ogrilp400

    ogrilp400 XS650 New Member

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    Yes I know that rolling element bearings only require a light stream of oil, drips even, as against plain bearings needing a good flow and pressure. Do XS 650s' have ball or roller BE bearings?
     
  5. Purplezinger

    Purplezinger XS650 Addict

    The connecting rod, big end bearings are splash lubed.
     
    Last edited: Oct 30, 2011
  6. ogrilp400

    ogrilp400 XS650 New Member

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    Thanks Purplezinger, I found it hard to believe too.
     
  7. Purplezinger

    Purplezinger XS650 Addict

    A side note, Chevy straight 6's had low pressure oiling with splash paddles (on the connecting rods) until (I believe) 1953. I think starting in 1954 Chevy had high pressure oiling.
     
  8. jayel

    jayel #9 Guru 74 TX650A

    ball bearings
     

    Attached Files:

  9. This one?
     

    Attached Files:

  10. XSLeo

    XSLeo XS650 Guru

    The oil gallery across the front of the engine that feeds the oil supply line to the head has ports on the inside of the case that squirt oil on the rod big ends. If you look in Jayel's pic you will see them. Just above the dark line thar shows the oil, just in line with the rods.
    The the alternator side and the two center crank bearings get oil pumped to them. The clutch side bearing runs in oil. The oil level is high enough so the crank runs in oil too. This splashes oil up on the botom of the pistons as well as the rods. This helps cool the pistons
    The crank being built up out of several parts can not carry oil to the rod big ends.
    Leo
     
  11. Purplezinger

    Purplezinger XS650 Addict

    Opps! my bad, the crank is pressed together. no oil passages. I knew that, The big ends have to be splash lubed
     
  12. gggGary

    gggGary Old guy, NO expert.

    Jayal and Aldo; yeah, both of those drawings.
     

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