help i need a piston xl600

Discussion in 'Thumpers' started by sh0rtlife, Nov 8, 2012.

  1. sh0rtlife

    sh0rtlife Been here awhile

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    ok guys..im lost and confused....i need a piston for my 83 xl600r..
    first off i am NOT looking for more power/compression....the bore was scored soo bad shes gotta go over to a .5 aka honda part 13103-MGB-003...HOWEVER it seems said part is obsolete ...ive allready got the jug honed out and cleaned ready to go..so anything SMALLER is NOT and option..i dont mind going bigger if i have to..but id rather not

    soo..is there anyone out there who can find me a slug and rings?
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  2. helipilot650l

    helipilot650l Sweet!!!!!!

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    XR'S only has many pistons for the XL600 which is the same as an xr600 :deal
    #2
  3. sh0rtlife

    sh0rtlife Been here awhile

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    unless i missed something..they are all 10.5+ comp...but ill go dig again.....isnt stock 9.0? or something close to that?
    as i said im not looking for more performance..just stone stock reliability
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  4. helipilot650l

    helipilot650l Sweet!!!!!!

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    I have been running mine for 25,000 miles with zero problems. They run much better with the big piston. The only other option it resleeve and stock piston. XR's sells and installs the sleeves. I am telling you this big bore kit is awesome.
    #4
  5. sh0rtlife

    sh0rtlife Been here awhile

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    which one are you running..i dont want to go crazy with it..as it does see ALOT of street time..but its looking like my ONLY option....im also lookin for a good rod as well just to be on the safer side of things
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  6. helipilot650l

    helipilot650l Sweet!!!!!!

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    I am running the 10:5.1 piston 618 cc. XR's Only also has the Con rod your looking for. Still Honda Reliable!!!:deal
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  7. XRider

    XRider Almost Lifelike

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    I've built quite a few XR600s and even a few XL600s and I have yet to see one in stock form (or nearly stock) with a broken rod. If it were me I wouldn't bother replacing the rod unless the big end bearings are shot or there's to much play at the wrist pin. I can highly recomend both the XRs Only and JE 10.5 c/r pistons, I've had nothing but good luck with them.

    Freshen up your top end, leave the bottom end alone, and you'll probably get another 10 years out of the Big 6.
    #7
  8. sh0rtlife

    sh0rtlife Been here awhile

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    ok..slightly confused as im looking at the slugs....everything seems to say 85 and up...but ive got an 83....did something change in 85?....am i right in assuming that since it went.5 over i need a 98mm?
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  9. XRider

    XRider Almost Lifelike

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    Are you sure you've got and '83? In '83 I thought the XRs and XLs were 500cc, not 600cc. I could be wrong but you might want to re-check the stearing head plate on your bike.
    #9
  10. katbeanz

    katbeanz earthbound misfit, I

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    They were 600's in 83, I had one, two actually when I acquired a parts bike. I think actual displacement was around 587 and twin carbs.
    #10
  11. sh0rtlife

    sh0rtlife Been here awhile

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    being the jug is still at the machinist i cant check the cc but i thought it was 597

    and yes its a 83 without question..both the # on the block and the # on the frame state 83 useing the break down from my books..AND its titled and PLATED as such...so if its NOT an 83...then the DMV screwed up a long time back :deal............i dont remember off hand was it 83 or 83 that was the first year for the 600r..i know the old style engine for the 500 was 79-81 but i dont remember what happened in 82(ive got an 80 500xl)

    i useualy dont have a problem making sense of this stuff..atleast on all the car engines ive built both stock and full race....but this whole going MM and speaking inches at the same time is totaly scrwing with me as well as the fact everyone lists 85+ but doesnt list 83/84 which i THOUGHT was the same engine internals......my understanding was its what 83till the last of the air cooled 600s right?..with the exception of the nikasils
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  12. Ghost_Mutant

    Ghost_Mutant looking for bionics

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    The big bore dry sump RFVC started in 83 with the XL600s and XR500s. Same models in 84. I have the 83 and 84 XR5s which have the dual carbs just like the XL6.

    In 85 Honda introduced the XR6 which also had the dual carbs until 87.

    The 82 and earlier XL/R 500s are the older engine design.

    To my knowledge all years of USA XL6s have the same bore and stroke and have regular cylinder sleeves. So I would think pistons are interchangeable for these years, but I've never worked on one as I found the XR5 in my price range first:lol3

    I did have a hard time finding oversized Honda pistons to use in my rebuilds. For the last one I bought, I emailed several Honda dealers that do on-line ordering and just asked if they could find me a NOS 0.50 83/4 XR500R piston on the shelf for sale. Most replied that they didn't want my business, but one local dealer said they would search their network and they did come through for me. The piston came in a 25+ year old box that was falling apart:roflBut the piston itself was NOS just as promised.

    Make sure you get the right clearance for the piston you have. The stock cast piston have narrower clearances than aftermarket forged pistons. The first guy I had machine a cylinder for me used the forged clearance when I had a stock cast piston. That combo used oil. I got tired of that and found the 0.50 and tried another machinist who used very tight clearances. Now the bike uses very little oil between changes. I'm reusing the 0.25 piston on a third/spare engine build that is slowly coming together.

    There are some transmission gear design differences between the XL6 years. But we're talking pistons here:rofl
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  13. helipilot650l

    helipilot650l Sweet!!!!!!

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    1983-1987 XL600 pistons are all the same. Put In a new piston and ride on.... I think you will be happy.
    #13
  14. kmequint

    kmequint Adventurer

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    For those inquiring minds. Just so you will sleep better information. 1983 XL600R

    [​IMG]
    #14
  15. sh0rtlife

    sh0rtlife Been here awhile

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    589 lol...i was soooo close

    ok soo in my hunt for the right slug....if i do have to go up in compression what piston do i need?....soo bloody confused its annoying me:huh

    im guessing as i dont have my book in front of me...stock is 97mm so i need a 97.5 or a 98...can the stock sleeve handle 98?
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  16. Wattner

    Wattner Long timer

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    CycleWizard to the red phone!

    Cyclewizard@aol.com for anything and everything XR/L.... He can make one for you
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  17. XRider

    XRider Almost Lifelike

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    98mm in no big deal at all! I bore XR600s to 100mm (628cc) all the time. Some people will even go to 101-2mm but unless it's a total effort race engine 100mm is as big as I like to go (on the stock sleeve).
    #17
  18. brucifer

    brucifer Long timer

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    Stock XL600 bore is 100 mm. They have a short 75 mm stroke.
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  19. XRider

    XRider Almost Lifelike

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    Oops, I think he's right.
    #19
  20. sh0rtlife

    sh0rtlife Been here awhile

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    ok that makes no sense ....no way the stock bore is 100mm..everything ive found says its 97mm...or is that part of the change from 83 to 85?
    #20