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  1. #1

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    what do these pistons look like ?

    I am trying to figure out the reason for damage. the upper rings in the outer cylinders broke apart and damaged the piston and heads and i dont know if the dimple in the piston is melt or just from impact.. someone shed some light ? the 2 pistons wash looks to me like a good mix .. far right im not so sure .. dont know if this is a fuel related prob or not ..
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  2. #2
    casey67's Avatar
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    The peices imbedded in the right piston looks like roller bearings from the wrist pin.
    The shavings in the head on the left head,could be wrist pin bearings???

    If it was just 1 cylinder,I would say the bearing let go. But 2 cylinders,makes me think it's an oil issue (the center was rich enough,to get lucky and survive)

  3. #3

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    thats what ive been told so far by k447, but all the bearings were fine.. soooo must be oil related or overheated .. well i guess ill just keep assembling and cleaning and checkin.

  4. #4
    bnasty's Avatar
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    Quote Originally Posted by dollaman View Post
    thats what ive been told so far by k447, but all the bearings were fine.. soooo must be oil related or overheated .. well i guess ill just keep assembling and cleaning and checkin.
    Were all of your circlips that hold the wrist pins in place still there?

  5. #5

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    yup everything in tact in there .. bottom end is mint too. i have no idea, just assuming all the damage was from the rings.

  6. #6
    SPEED KILLS, BUT YOU GET THERE QUICKER Keddano's Avatar
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    Lean,lean and lean. A good wash pattern will leave near the ports WASHED clean with fuel.Dark covered tops are too lean.I'd be looking at the fuel system,lines,etc.

  7. #7

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    ive got another thread started on this topic, however since this ones goin , i just found out last night while about to open and clean the carbs that there were no high speed fuel screws !!! they are missing, and some gunk in the mag end carb i beleive. could this have led to the big bang ?

  8. #8

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    AH HAA

    Well i did some detective work and found the original owners number ! .. I spoke witht he guy and he told me he had it for 5 years and never cleaned the carbs, even with decreasing power and performance. He pretty much confirmed what i needed to hear (that the problem was all carb related) from what he explained... and that it needed to be cleaned and tuned properly a long time ago .. he didnt even have a clue about the fuel screws or where they are on the carbs... so the chances they came out (if thats even possible ) is definately plausible .. lol this guy was clueless thought power would come back if he drove it more .... anywyas i think i know what i gotta do now, but still looking to find the right model number for the high speed screws.... if anyone could help out that would be great.

  9. #9
    Moderator beerdart's Avatar
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    What ski is the carbs from???

  10. #10
    casey67's Avatar
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    It appears only a couple Keihin carbs had the high speed screws ( 96 SL700 being one) I get the impression the manual showed the 700 carbs and was never updated,causing alot of confusion.The service manual also shows the high speed jet screwing into the front of the jet block(true for the 96 700) All the other carbs I have seen,the jet is on the back of the block. I think it is safe to say none of the 3 cylinder models had the high speed screws.

    The 97 SLTX carbs I looked at recently did not have the high speed screws.
    It's unlikely all 3 would fall out. When the carbs are apart you will definetly see there is no passage for the screws.

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