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  1. #1

    Advice needed on triple pipe gpr

    Need some advice on what to do with my ski, I built a 1200r as follows: stock motor, new platinum WSM pistons, stock carbs re-jetted, factory pipe triples, high flow water box, stock PV's, advent ignition, flame arresters, new stock reeds, skimmed stock head - 150psi, premix oil - 40:1, hot rod crank, 13/19 skat-trak, riva grate, can't think of any other mods,

    built the ski and got it running, thought it always ran rich but struggled to tune it without T-bar mixture screws, tried to tune it the other day and ended up melting the side of the front (number 1) piston away against the exhaust port to the point where the top piston ring was exposed and broke off,

    Someone suggested putting it all back to stock so its reliable but ive sold my waterbox, and alot of stock parts or do I get better quality pistons, new barrels and get it tuned correctly but always have the tempromental pipes and list of things to go wrong? Does anyone have barrels, pistons, parts ill need? Cheers all


  2. #2
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    you will burn up any motor if your carbs are not dialed in. rebuild it and have someone tune it and dial it/break it in for you. are you positive it was a carb issue

  3. #3
    mudslanger's Avatar
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    Sending you a PM

  4. #4
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    If you decide to sell pipes let me know I just may buy them. I have a stock waterbox, jugs, ebox, pvs, etc if you go that route

  5. #5
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    Ck for leaks would be the most important step at this point. It didnt run right and the jetting should be kinda close from the posting on here. A pipe leaking water can size a piston just like that. It wont run right either and ur chaising a GREMLIN BY TUNING CARBS AND THAT MAY NOT THE PROBLEM ,probly. So pressure test the pipes, in the water jacket should hold 15 psi for at least 5 minuet. Pressure test the water jackets on the the cylinders bolted on to the block with the heads bolted on. Should hold says 40 psi for 5 min. also if that all cks good the pressure ck the cases.. Alos look at fuen filters shut off valve. If running 150 or so cranking compression u should be mixing a little race gas as they have a tendency to seize in the mid range around 7000 rpm. 135 is about the max on pump gas.
    It also depends on the ecu and timming.
    One thing I will grantee the cilinder that sized is crakked Period. Hope some of this helps u. U can send that to milluim and they can weld it up BUT you better test it when u get it back for a leak.

  6. #6
    I'm pretty sure it's carbs, its detonated away the side of the piston terribly so the ignition or fuel is bad, I'm 90% sure it's a carb issue because it was way out of tune which was my fault, I think ill shortly be selling the ski because I'm moving away so unfortunately she has to go, I'm not sure if its more sellable being stock and reliable or tempromental but crazy fast? What do people want? I live near Perth in Western Australia. If I convert back to stock I have to change all the pipe work from the water box to the hull because I have a custom outlet. Ill reply to the PM I've recieved but am not sure what to do, stock or modded? Can anyone price me up the difference with parts they have, e.g barrels , pistons, carb parts, postage... Or an offer swapping to convert mine to stock? Cheers guys

  7. #7
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    Your better off parting it out IMO. Depending on the damage the internals can be damaged. Selling as is wont fetch you much due to the internals being possible damaged. The jug as well may need a 300 renick, 160 piston kit, etc.

  8. #8
    Either way ill deftinatley fix it before I sell it, unless I can make as much parting it out easily? The crank looks fine and no debris has gone down the bottom end, I can either put 3 new pistons in and 1 new jug, tune it properly and sell it with the pipes or convert it back to stock, sell the upgrades that are on it and put it up for sale, the other thing I need is a new display / speedo, as mine got a crack in it which leaked water. Anyone?

  9. #9
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    Depending on the damage it may or may not be worth fixing and selling unless you throw it together just to get it running. Tear it apart and evaluate from there. How can you can tell no metal went into the cases without splitting them? I'd assume your guessing and hoping there isn't. Only way to truly tell is split cases. Should have had someone with experience break in motor and adjust carbs. Expensive lesson learned

  10. #10
    mudslanger's Avatar
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    Quote Originally Posted by Rocketman View Post
    Ck for leaks would be the most important step at this point. It didnt run right and the jetting should be kinda close from the posting on here. A pipe leaking water can size a piston just like that. It wont run right either and ur chaising a GREMLIN BY TUNING CARBS AND THAT MAY NOT THE PROBLEM ,probly. So pressure test the pipes, in the water jacket should hold 15 psi for at least 5 minuet. Pressure test the water jackets on the the cylinders bolted on to the block with the heads bolted on. Should hold says 40 psi for 5 min. also if that all cks good the pressure ck the cases.. Alos look at fuen filters shut off valve. If running 150 or so cranking compression u should be mixing a little race gas as they have a tendency to seize in the mid range around 7000 rpm. 135 is about the max on pump gas.
    It also depends on the ecu and timming.
    One thing I will grantee the cilinder that sized is crakked Period. Hope some of this helps u. U can send that to milluim and they can weld it up BUT you better test it when u get it back for a leak.
    +1 Great advice and some pics of everything damaged would help

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