Results 1 to 18 of 18

Thread: my first CB200 top end teardown and many questions...

  1. #1
    Member
    Join Date
    07.22.21
    Location
    REDMOND, WA, USA
    Posts
    38
    Thanks Thanks Given 
    2
    Thanks Thanks Received 
    3
    Thanked in
    3 Posts

    my first CB200 top end teardown and many questions...

    Hi Everyone,

    This is a continuation of multiple separate posts I've made over the last year or so related to:
    1) low compression, 2) bike dying at stop when engine was hot, 3) disparity in cylinder temps not fixable with carb adjustments, and 4) engine noises at idle.

    After trying each of the easy fixes suggested by all the guru's here, I wasn't seeing much change in the bike's behavior. One common suggestion previously was to address the compression problem... so I broke it open today to investigate further.

    The engine has 10k miles. it was given to me in pieces as a project bike.
    PO said it had been sitting for 10years with unknown engine condition.
    this is my first bike, and I have MANY questions for you all:

    Regarding Noises at Idle:
    I think it was ancientdad who suggested a loose/malfunctioning tensioner spring, and he was right.
    I was never able to get it to tighten up externally.
    Inside, the chain looks like it has been grinding into the cylinder head, with a deep enough gouge that it appears to be binding the spring mechanism.

    pretty sure this tensioner mechanism needs replacement, correct?

    Also, assuming I am able to deburr the hole that the tensioner spring is sitting in (that is causing sticky behavior) do I need to address the ground-away & missing material caused by slack chain hitting the head? or leave it?
    tensioner2.jpg


    Also, how typical is this tension mechanism idle sprocket wear?
    The nubby teeth here looks like it needs replacement, but I'm not sure how tall they are supposed to be. thoughts?
    spring tensioner roller.jpg


    Cylinder head has dark stain near Left Cylinder (top of the photo below). Does that suggest headgasket blowby?

    And what is going on with Right Cylinder exhaust valve tan coloring? is this evidence of overheating?
    Its worth noting was that this was always the "hot" cylinder... 30-40deg F higher than Left.

    head.jpg

    Regarding Compression - the cylinder walls are rough on both. I assume this was the source of bad compression although I was expecting much much worse given the atrocious compression readings (~100-110 psi). note, the lighting in the image makes it look much rougher than reality. I will try honing first, i think.

    cylinder.jpg

    Rings are intact / not broken. Pistons appear fine.
    Other than dimensional checks called out on each in the FSM, what else should I look for to determine if they need replacement?

    I know that's a lot all at once!... but as usual - thank you for your help!
    Attached Images Attached Images

  2. #2
    Benevolent Dictator ancientdad's Avatar
    Join Date
    05.21.20
    Location
    Nature Coast, FL
    Posts
    16,314
    Thanks Thanks Given 
    2,692
    Thanks Thanks Received 
    4,067
    Thanked in
    3,197 Posts
    The condition of the pistons is irrelevant at this point, the cylinders have rust rings from hell and that is likely why the compression was so low. You'll need to go at least 2nd oversize on the cylinders (0.50mm), maybe more, to get that cleaned up. It probably sat for a very long time somewhere along the way before you got it, got stuck and was later unstuck and revived but not rebuilt. The valve color probably relates to that cylinder running better than the other one. As for the cam chain wear - ugly for sure - once you get it completely apart and clean you can inspect the area to be sure it didn't get worn all the way through into either the passage for the cam chain adjuster rod or the outside which would present an oil leak. Oh, and the cam chain tensioner roller is shot but the little nubs are not the worst part, it's the caved-in look of the rubber roller elsewhere from getting pummeled by the loose chain.
    (move along, nothing to see here)

  3. #3
    Senior Member Flyin900's Avatar
    Join Date
    11.27.20
    Location
    Canada
    Posts
    595
    Thanks Thanks Given 
    100
    Thanks Thanks Received 
    243
    Thanked in
    178 Posts
    As AD noted lots or worn out parts in there. I had some of the same wear on the tensioner and associated parts on my CL175. If your going to do it right it needs everything that is part of the cam chain and tensioner system replaced. That means the lower rubber roller the cam chain first hits when leaving the crankshaft below your tensioner picture. The tensioner teethed roller and the complete pusher rod assembly and that spring for sure. A new cam chain is a must too, as it has been hitting the barrels side per the gouges.That deep gouge is typical of no maintenance by a PO letting the cam chain run too slack.

    You can use some high temp JB Weld to rebuild that worn area in the cylinder wall which will strengthen that part, as the slider rod of the adjuster runs through there. Honing will not fix that cylinder issue and OS pistons may be available from a British supplier IMD pistons, if you can't find any OEM NOS Honda ones.

    A valve job with attention paid to the thickness of the valve side faces, as with time they tend to wear quite thin over time. A lapping will not work well if they are badly worn away. All these parts should be available, yet it starts to add up $$$ doing a rebuild of these worn parts.
    1966 CL77 - 305cc - Gentleman's Scrambler
    1967 CL175K0 - Scrambler #802 engine
    1972 CB350F - Candy Bacchus Olive - Super Sport
    1973 CB350F - Flake Matador Red - Super Sport
    1975 CB400F - Parakeet Yellow - Super Sport
    1976 GL1000 - Goldwing Standard
    1978 CB550K - Super Sport

  4. #4
    Senior Member
    Join Date
    06.01.20
    Location
    Worcester, England
    Posts
    1,619
    Thanks Thanks Given 
    122
    Thanks Thanks Received 
    471
    Thanked in
    369 Posts
    These are pictures of a brand new 175 cam tensioner assembly. Not quite the same as the CB200, but principal is the same, this is what the tensioners wheels should look like.

    The toothed wheel is pretty much unobtanium, unless you get lucky and find a complete NOS tensioner assembly. Capellini do a replacement steel wheel with needle roller bearings, at a price.







    1972 CL175K7
    1970 CB174K4, 'upgraded' to a K6 alike
    1971 SL175, with a few non standard parts !
    1998 CB600 Hornet

  5. #5
    Senior Member Flyin900's Avatar
    Join Date
    11.27.20
    Location
    Canada
    Posts
    595
    Thanks Thanks Given 
    100
    Thanks Thanks Received 
    243
    Thanked in
    178 Posts
    Richard, will the CL175 tensioner assembly work in his CB200 motor. Since CNSNL has the complete assembly still available for the CL175 at a decent price.
    1966 CL77 - 305cc - Gentleman's Scrambler
    1967 CL175K0 - Scrambler #802 engine
    1972 CB350F - Candy Bacchus Olive - Super Sport
    1973 CB350F - Flake Matador Red - Super Sport
    1975 CB400F - Parakeet Yellow - Super Sport
    1976 GL1000 - Goldwing Standard
    1978 CB550K - Super Sport

  6. #6
    Senior Member
    Join Date
    06.01.20
    Location
    Worcester, England
    Posts
    1,619
    Thanks Thanks Given 
    122
    Thanks Thanks Received 
    471
    Thanked in
    369 Posts
    Quote Originally Posted by Flyin900 View Post
    Richard, will the CL175 tensioner assembly work in his CB200 motor. Since CNSNL has the complete assembly still available for the CL175 at a decent price.
    No, the actual pressed metal frame of the CB200 tensioner is longer, also the rubber idler wheel is larger. The idler wheel was available from David Silvers last time I looked. I suppose at a pinch one could buy the 175 part and transfer the toothed wheel across, although that would not be straight forward, as Honda fixed the wheel in place by riveting over the central axle.
    1972 CL175K7
    1970 CB174K4, 'upgraded' to a K6 alike
    1971 SL175, with a few non standard parts !
    1998 CB600 Hornet

  7. #7
    Senior Member
    Join Date
    06.01.20
    Location
    Worcester, England
    Posts
    1,619
    Thanks Thanks Given 
    122
    Thanks Thanks Received 
    471
    Thanked in
    369 Posts
    1972 CL175K7
    1970 CB174K4, 'upgraded' to a K6 alike
    1971 SL175, with a few non standard parts !
    1998 CB600 Hornet

  8. #8
    Senior Member ballbearian's Avatar
    Join Date
    11.21.21
    Location
    Hagerstown MD USA
    Posts
    1,875
    Thanks Thanks Given 
    1,114
    Thanks Thanks Received 
    639
    Thanked in
    528 Posts
    The last pic in Vinty's #1 post shows a compressed pushrod. The tensioner then never had a chance to do it's job. Hard to see much of the tensioner yet, wait till it's out and inspected before deciding it must be replaced. If the pad that the push rod pushes on, on the other end of the tensioner is solid, and the nubby roller is not breaking down, I'd get a new chain and push rod and spring if needed and go with it. Other tensioners don't even have the knobby wheels, like the 160's, 305's so I wouldn't worry on that if the rubber is still intact and somewhat supple.

    Stuck push rod looks to me like the culprit and possible miss route of the cam chain as well because the chain should never have been that close to the front tunnel wall unless the chain was outside (or front) of the push pad of the tensioner. It will be evident when the tensioner is removed and chain wear is seen on the outside or front of the push pad. The more I think about it that would also explain the stuck push rod because the chain would prevent the rod from pushing on the pad.
    Last edited by ballbearian; 11.24.22 at 11:27 AM. Reason: meant front instead of rear

  9. #9
    Senior Member
    Join Date
    06.01.20
    Location
    Worcester, England
    Posts
    1,619
    Thanks Thanks Given 
    122
    Thanks Thanks Received 
    471
    Thanked in
    369 Posts
    That wear in the CB200 head is typical of a very slack but correctly routed cam chain.

    Differences in the 175 and 200 parts:

    CB200 tensioner on the right side of this photo, 175 on the left.

    1972 CL175K7
    1970 CB174K4, 'upgraded' to a K6 alike
    1971 SL175, with a few non standard parts !
    1998 CB600 Hornet

  10. #10
    Senior Member
    Join Date
    06.01.20
    Location
    Worcester, England
    Posts
    1,619
    Thanks Thanks Given 
    122
    Thanks Thanks Received 
    471
    Thanked in
    369 Posts
    Wear pattern in my CB200 head.

    1972 CL175K7
    1970 CB174K4, 'upgraded' to a K6 alike
    1971 SL175, with a few non standard parts !
    1998 CB600 Hornet

  11. #11
    Senior Member ballbearian's Avatar
    Join Date
    11.21.21
    Location
    Hagerstown MD USA
    Posts
    1,875
    Thanks Thanks Given 
    1,114
    Thanks Thanks Received 
    639
    Thanked in
    528 Posts
    Waiting to see if wear on the outer edge of the push pad on the tensioner. With that much extreme wear on the inside of the rod, it wouldn't surprise me.

    I know I don't have anywhere near the experience that a lot of guys here do, but I'm just thinking and watching. Being a bonafide victim of incorrect PO assembly, myself.

  12. #12
    Senior Member ballbearian's Avatar
    Join Date
    11.21.21
    Location
    Hagerstown MD USA
    Posts
    1,875
    Thanks Thanks Given 
    1,114
    Thanks Thanks Received 
    639
    Thanked in
    528 Posts
    Quote Originally Posted by Richard Pitman View Post
    Wear pattern in my CB200 head.
    I see what you mean. Right, not likely.

  13. #13
    Senior Member Flyin900's Avatar
    Join Date
    11.27.20
    Location
    Canada
    Posts
    595
    Thanks Thanks Given 
    100
    Thanks Thanks Received 
    243
    Thanked in
    178 Posts
    Yes my CL175 I did exhibit those same marks on the barrels, yet not as bad as the posters's part. It is a sign of no maintenance, or lack of cam chain tensioning. The issue is most of those wear items are 50+ years old and the rubber is like a hockey puck hard and fragile. Eventually there will be no choice but to reuse, or buy used parts for many of these bikes. I did a quick search for the parts he may need and most items are already gone from the key suppliers, with some items available if your willing to buy at top dollar from various vendors for additional shipping expenses.

    A case in point is the 219/82 link cam chain he will need. Many are still available in a endless loop or a peen style link, although very few in this last style. The chains from RK and DID with a removable split link are pretty well gone now. I searched for a friend yesterday for his CB350F motor rebuild and came up dry for this style. He doesn't want to split the cases, yet that is likely the route he will need to go now.
    1966 CL77 - 305cc - Gentleman's Scrambler
    1967 CL175K0 - Scrambler #802 engine
    1972 CB350F - Candy Bacchus Olive - Super Sport
    1973 CB350F - Flake Matador Red - Super Sport
    1975 CB400F - Parakeet Yellow - Super Sport
    1976 GL1000 - Goldwing Standard
    1978 CB550K - Super Sport

  14. #14
    Administrator LongDistanceRider's Avatar
    Join Date
    05.22.20
    Location
    Vancouver, Washington USA
    Posts
    7,886
    Thanks Thanks Given 
    1,231
    Thanks Thanks Received 
    2,453
    Thanked in
    1,924 Posts
    My concern is the depth of the wear on the head. Roughly looks like 50% of that area is worn away and since it a structural area supporting the chain tensioner I'm concerned it might break loose with the pressure of the lock bolt pushing on the shaft.
    Jim O'Brien
    1979 CM400T aka the Roadbike, 1978 CB400T1 semi restored, 1972 CL350K4 restoration and the 1971 SL350K1 disaster zone.
    Plus 2 SL350K0's , 2 SL350K1's, 1 CL350K0 and 1 CL350K1 waiting for space and time
    Contact: 408-239-9580 or [email protected]

  15. #15
    Senior Member Flyin900's Avatar
    Join Date
    11.27.20
    Location
    Canada
    Posts
    595
    Thanks Thanks Given 
    100
    Thanks Thanks Received 
    243
    Thanked in
    178 Posts
    Jim as noted above in my post that area can be strengthened/rebuilt with a JB Weld metal epoxy that will reinforce it more than adequately. I agree that it is probably very close to wearing through into the tunnel of the adjuster rod. I did the same repair on my CL175, yet it wasn't worn as badly as that one. I like the Tech Steel metal epoxy as you know, since I feel it is a superior product to the JB Weld, yet it may not be as easily obtainable as the JB products in the USA.
    1966 CL77 - 305cc - Gentleman's Scrambler
    1967 CL175K0 - Scrambler #802 engine
    1972 CB350F - Candy Bacchus Olive - Super Sport
    1973 CB350F - Flake Matador Red - Super Sport
    1975 CB400F - Parakeet Yellow - Super Sport
    1976 GL1000 - Goldwing Standard
    1978 CB550K - Super Sport

  16. #16
    Administrator LongDistanceRider's Avatar
    Join Date
    05.22.20
    Location
    Vancouver, Washington USA
    Posts
    7,886
    Thanks Thanks Given 
    1,231
    Thanks Thanks Received 
    2,453
    Thanked in
    1,924 Posts
    Quote Originally Posted by Flyin900 View Post
    Jim as noted above in my post that area can be strengthened/rebuilt with a JB Weld metal epoxy that will reinforce it more than adequately. I agree that it is probably very close to wearing through into the tunnel of the adjuster rod. I did the same repair on my CL175, yet it wasn't worn as badly as that one. I like the Tech Steel metal epoxy as you know, since I feel it is a superior product to the JB Weld, yet it may not be as easily obtainable as the JB products in the USA.
    I saw that but I'm still not sure that would be adequate, welding would for sure. Looks like Tech Steel might be available thru CarQuest or Napa stores.
    Jim O'Brien
    1979 CM400T aka the Roadbike, 1978 CB400T1 semi restored, 1972 CL350K4 restoration and the 1971 SL350K1 disaster zone.
    Plus 2 SL350K0's , 2 SL350K1's, 1 CL350K0 and 1 CL350K1 waiting for space and time
    Contact: 408-239-9580 or [email protected]

  17. #17
    Member
    Join Date
    07.22.21
    Location
    REDMOND, WA, USA
    Posts
    38
    Thanks Thanks Given 
    2
    Thanks Thanks Received 
    3
    Thanked in
    3 Posts
    Thanks all for the feedback. Really helpful. I'll keep you posted after I clean it up.

    Sent from my GM1915 using Tapatalk

  18. #18
    Benevolent Dictator ancientdad's Avatar
    Join Date
    05.21.20
    Location
    Nature Coast, FL
    Posts
    16,314
    Thanks Thanks Given 
    2,692
    Thanks Thanks Received 
    4,067
    Thanked in
    3,197 Posts
    Quote Originally Posted by vinty200 View Post
    Thanks all for the feedback. Really helpful. I'll keep you posted after I clean it up.

    Sent from my GM1915 using Tapatalk
    And post close-up pictures of the worn areas
    (move along, nothing to see here)

Posting Permissions

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