CB200 crankshaft
Results 1 to 5 of 5
Like Tree1Likes
  • 1 Post By Quixote

Thread: CB200 crankshaft

  1. #1
    Senior Member Kawastoney's Avatar
    Join Date
    Dec 2013
    Location
    Orange, NSW, Australia
    Posts
    166

    CB200 crankshaft

    A friend is rebuilding a CB200, very slowly, on my workbench. She has now got the crank cases apart. Some bits needed drilling to get them out so some aluminium grindings have gone into the engine. The only part that seems to be affected is the crank shaft. After taking the barrels off it turned smoothly with no play. Now it is out the right con rod feels gritty at the big end. It turns, but not as smoothly.
    Questions
    1. Can the crank shaft be disassembled and the big end bearing replaced?
    2. Would it destroy itself if it was reassembled and run as it is? or would the aluminium just melt and free up the bearing?
    3. Would a replacement crank shaft be likely to be in just as bad condition?
    4. What haven't we thought of?

    Thanks for any advice.
    Peter and Susan

    1975 CB200 drum brake rebulid
    Peter

    CB175K3 build

    "Temporary Australian"

  2. #2
    Senior Member brush439's Avatar
    Join Date
    May 2011
    Posts
    185
    chances are it would go bang big style
    you'll have to get an engineering company to split it... the cranks are pressed

  3. #3
    Senior Member Kawastoney's Avatar
    Join Date
    Dec 2013
    Location
    Orange, NSW, Australia
    Posts
    166
    Quote Originally Posted by brush439 View Post
    chances are it would go bang big style
    you'll have to get an engineering company to split it... the cranks are pressed
    Thank you Brush439.
    I'll see what the local engineering company says.
    Peter

    CB175K3 build

    "Temporary Australian"

  4. Remove Advertisements
    HondaTwins.net
    Advertisements
     

  5. #4
    Supporting Member Quixote's Avatar
    Join Date
    Oct 2014
    Location
    Derby, Kansas
    Posts
    1,159
    Quote Originally Posted by Kawastoney View Post
    A friend is rebuilding a CB200, very slowly, on my workbench. She has now got the crank cases apart. Some bits needed drilling to get them out so some aluminium grindings have gone into the engine. The only part that seems to be affected is the crank shaft. After taking the barrels off it turned smoothly with no play. Now it is out the right con rod feels gritty at the big end. It turns, but not as smoothly.
    Questions
    1. Can the crank shaft be disassembled and the big end bearing replaced?
    2. Would it destroy itself if it was reassembled and run as it is? or would the aluminium just melt and free up the bearing?
    3. Would a replacement crank shaft be likely to be in just as bad condition?
    4. What haven't we thought of?

    Thanks for any advice.
    Peter and Susan

    1975 CB200 drum brake rebulid

    1. Yes the crankshaft can be dis-assembled and the bearing can be replaced, however I think you may have a simple issue (more in a moment)

    2. There is no aluminum in the design... so I'm not sure what you are looking at. The large end uses needle bearings. Its not conventional like babbit bearings like your car.

    3. You can get a good clean one or a dirty one on Ebay

    4. Try this 1st. Soak the offending end of the crankshaft in a degreaser (overnight). This will help loosen probable hardened debris (crunch feeling stuff). To help remove the debris use a spray wand (w/solvent) into the oil feed hole of the crankshaft bearing. This will help force debris out between the large end of the rod end and the crankshaft bearing. Repeat until smooth. If this works out, squirt some CLEAN oil in there to prevent rusting. Your done.

    NOTE: The crankshaft acts like an oil filter with its spinning action and will collect debris. If its been sitting awhile this can harden over time and produce the crunchy feel. The camshaft also acts like an oil filter due to the spinning action, and debris will collect down the center section.

    5. Now if you want to take the crankshaft apart... you can read how to do this (I've done two of them for the CB175and its the same in design as your 200. Carefully read through this link starting with thread #73 onward, as this describes how to dis-assemble the crankshaft. At this link, I describe my 1st time trying this so there was a lot of caution... but I can assure you its really quite easy to do (if you have appropriate equipment).

    This should take you to my thread #73
    1971 CB175 (K5) - Rebuilding Miss Daisy

    Cheers
    HondaCB200Lady likes this.
    - Jack -

    "Sometimes the fastest way to get there is to go slow
    And sometimes if you wanna hold on you got to let go"
    Count to Ten/Tina Dico

    1971 CB175 (K5) - Rebuilding Miss Daisy
    http://www.hondatwins.net/forums/1-p...n-rebuild.html

  6. #5
    Senior Member Kawastoney's Avatar
    Join Date
    Dec 2013
    Location
    Orange, NSW, Australia
    Posts
    166
    Aluminium was from something that had to be drilled to get the engine apart. Crankshaft has been washed with petrol, then bearings blown with a can of degreaser. This got all but one bearing running smooth again.
    I'll have a look at your thread.
    Thank you Quixote.
    Peter

    CB175K3 build

    "Temporary Australian"

Sponsored Links

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •