~~~1983 Honda XL600R Total Engine Rebuild~~~

Discussion in 'Thumpers' started by BThresher183, Jan 12, 2015.

  1. BThresher183

    BThresher183 Adventurer

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    Was able to take off the clutch and drive gear off finally. I used a rubber strap oil filter wrench to hold the inside of the clutch so that I could remove the nut. Was going to take the transmission out and the rest but I am worried about not being able to get everything back together like it should be. I have written things down and taken pictures, but still. I am still weighing my options for the gaskets. Will probably order from ebay today.
    #21
  2. mcma111

    mcma111 Long timer

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    When I do an engine rebuild I only order the gaskets and seals that I will be needing. Those kits give you pieces that you may not need. Price out just what you need and compare to the kit.
    #22
  3. brucifer

    brucifer Long timer

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    You don't need to take anything out if you don't want to. When you split the cases, everything stays in the left hand case. Just lay the engine on the left side and remove the right case. Keep your eyes open for washers (shims) on the end of the transmission shafts etc. Sometimes they'll stick to the right case when separating.
    Have a good look at the transmission gears to see if they are pitting. If any are found to have pitting, they need to be replaced.
    #23
  4. BThresher183

    BThresher183 Adventurer

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    Thanks for that info. I am actually really impressed with this bike. The lower (and upper) are extremely clean and all the gears look like new. Really good condition. I'll try to post up some pictures. But I will try to go through it to look for any abnormalities. I am worried about missing any washers etc. I will just try to research each assembly to double check. But that old gasket was in rough shape so I am pretty confident that, that is where the leak was coming from.
    #24
  5. brucifer

    brucifer Long timer

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    I've gone through the same thing you're going through now.
    I bought an ebay lower end for my '84 XL600 and after looking it over felt I could use it as is. Built a nice performance top end using a JE piston and Megacylce cam and rockers. Put about 50 miles on it and noticed an oil leak coming from the main case parting line at the front where the balancer is. :bluduh
    Out came the engine and a complete tear down. Replaced the main gasket and reassembled with a performance XR600 top end. That engine went into a plated 2000 XR600 that I sold to my neighbor a handful of years ago and it's still going strong.
    #25
  6. BThresher183

    BThresher183 Adventurer

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    Here are some shots of where I am at right now.

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    #26
  7. BThresher183

    BThresher183 Adventurer

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    I was going back and forth with the idea of a different top end, bigger piston etc. I think it will be a miracle if the engine runs after this haha. This is my first time taking any engine apart, so it will be an experience. The cylinder looks good, and I think I will purchase a new piston and rings, just because. Also, a new cam chain since I'm down there. All new seals and gaskets. My other goal is to try to completely de-grease the outside of the engine. Years of driving it with a small-moderate oil leak has made a mess of the engine and the frame.
    #27
  8. mcma111

    mcma111 Long timer

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    Before you go out buying a new piston take the cylinder and piston to a machinist and have them measured. I would have the cylinder honed and then measured. If they are still in spec you could get by with just a new set of rings.
    #28
  9. BThresher183

    BThresher183 Adventurer

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    Gotcha, I will check into that!
    #29
  10. BThresher183

    BThresher183 Adventurer

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    I ended up Just ordering the Vesrah kit on ebay. So I didn't have to guess which part numbers I needed, and the oring I am looking for list 2 different sizes for the same thing. I was going to make this a 2-3 year project, but I really want to jump back on this bike this summer and enjoy the ride. Really wanted to make it more of a motard style, or even more a a drag looking style. Was toying with the idea of extending the swingarm, but that comes with its own set of headaches.

    I appreciate the help from everyone. I will try to get my cylinder checked out before I throw it back together. The piston is in great shape, just had a little bit of buildup on the top of it. But It look brand new. What is the rule for piston and cylinder size? How do you know what size to get? Thanks!
    #30
  11. BThresher183

    BThresher183 Adventurer

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    Just wanted to share some pictures of my thumper. Although these pictures were from a while back, it is pretty much identical (except dirtier and oilier...) I do have an aftermarket seat cover, and I do have the side plastics, I was just charging the battery I think. I ended up replacing both front and back fenders with universal aftermarkets. The back one has always looked a little weird. Would love to find something that looks closer to the original. Also have more street tires on it now, and its plated.

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    #31
  12. BThresher183

    BThresher183 Adventurer

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    Also, Here is a picture of the piston, and a more updated picture of the bike.


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    #32
  13. tcepilot

    tcepilot Been here awhile

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    Are engine bearings available still? Mine will be needing a rebuild before too long. Valve seals are bad. I don't know what's been done to it since 83 so I want to rebuild it and have a new bike. I just want to know if and where I can find all of the parts.
    #33
  14. BThresher183

    BThresher183 Adventurer

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    #34
  15. brucifer

    brucifer Long timer

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    Looks like you have an aftermarket piston.
    #35
  16. BThresher183

    BThresher183 Adventurer

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    I assume that it is. The top end was rebuilt a year or two after I bought the bike. Looks the be in ok shape. Not sure if I should reuse or not.
    #36
  17. brucifer

    brucifer Long timer

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    It looks to be in nice shape in your pic. If it and your cylinder measure within spec there's no reason you shouldn't reuse it.
    Keep in mind a forged piston such as you have will require looser tolerances than the stock cast one.
    #37
  18. BThresher183

    BThresher183 Adventurer

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    I should be able to measure the inside of the cylinder with a caliper, as well as the piston. Is this the best way to get those measurements? What are the tolerances between piston and cylinder?
    #38
  19. mcma111

    mcma111 Long timer

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    You can't get an accurate measurement with a caliper. Only a rough reading. You need an inside bore gauge and a micrometer for 4". You measure the cylinder top, middle, bottom front to rear and side to side. Anything less and your just fooling yourself.
    #39
  20. BThresher183

    BThresher183 Adventurer

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    That's what I was wondering. I know that it is recommended to go through all of this, but I will weigh the risk. The cylinder and piston look in excellent condition. I can only think there is only a couple thousand miles on the engine at most since the rebuild, So I can't imagine it needed too much work. Always had clean synthetic oil in it with regular changes and oil filters. I will check the clearances between the piston and cylinder when I get to a point of putting it back together. What is recommended when putting the crankcase back together. Should I be putting grease on the bearings moving parts?

    I just received my left side crank case in the mail (put a hole through the original when trying to split the cases) and the gasket kit should be coming tomorrow. Working on de-greasing and cleaning up the crankcase before putting it back together.
    #40