Looking to buy the new M/M head...

Discussion in 'Motorized Bicycle General Discussion' started by The 26incher, Apr 18, 2010.

  1. The 26incher

    The 26incher New Member

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    Hey guys, Could we get some feed-back on the new Manic Mechanic head for use on a GT5. I know for $45 you can beat the price but what kind of luck have you guys had with it? Also, would it be better to buy a hotter or cooler spark plug? Where I live it's almost always 75 and sunny. I know I'm going to buy it for the "show" factor but I also want it to "GO!" Any input will help. Thanks
     
  2. stuartracing

    stuartracing New Member

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    I just installed it om my motor last week and it has made big time difference`s...It came with a B8S short reach plug.....I`ve got about 25 30 miles on it so far with zero issues.....I did try to do a compression test today and got about 2 half cranks with the pedals and it jumped up to 125 psi with just that.....I suspect it will have some excellent comp.....My torque is awesome from idle all through the power range with zero 4stroking.....I got off the throttle at 35 mph and had should put my infared heat gun on it to check on the temp.....I am running a NT Speedway carb. And a lawnmower muffler exh. pipe.....I love the power curve this billet head deliver`s, very noticeable....
    Paul....
     
  3. longhair

    longhair New Member

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    [QUOTE=The 26incher;


    Hey 26er. where the heck were you? we missed ya......... Awesome ride with good beer stops for you boozers, and BBQ..duh.
     
  4. Creative Engineering

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  5. Creative Engineering

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    Paul summed it up nicely!

    The combustion chamber in my billet head was designed for an engine that has nearly zero deck height and a crowned piston. The PK80 and the Grubee GT-5 were checked and tested with good results.

    Jim
     
  6. Creative Engineering

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    Please don't take offense, but your post reads like I am offering a cylinder head of unknown performance qualities.

    I know it's hard to believe, but I physically make these parts from raw blocks of Aluminum. I go to great lengths to ensure that everything I make offers the buyer a real benefit.

    There is no "luck" involved, just hard work and testing!

    You will likely need a 7 or 8, (NGK), heat range plug depending on how your engine is tuned. The higher the number the colder the plug with NGK. Use 93 octane fuel!

    Jim
     
  7. GeneFiorot

    GeneFiorot New Member

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    Elegantly said my Man Home Run Jim!
     
  8. stuartracing

    stuartracing New Member

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    I`ve been running the SUNOCO 100 octane race fuel.....With a fuel oil mixture of 3 oz`s to a gal....No pre ign. detonation at all....Plug color is on the dark/safe side....So I`m giving up a little hp there..... $45 well spent...
     
  9. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    Hey Jim, I posted this in another thread about your new heads... I'll ask here too...

    It's my understanding that the PK-80s need to have two head gaskets to keep the piston from hitting the stock head, right?
    When you made these heads, did you make them so that they only need one gasket instead of two?,
    & what happens if someone trys to bolt one of these on a engine other than a PK-80??? (will the compression be too low?)
     
  10. Creative Engineering

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    Sorry I didn't answer your question in the other thread Norm.

    The PK-80's are assembled with 2 head gaskets. I'm not sure what the thinking was with that, but it is totally unnecessary.

    Yes you are absolutely right about compression and other engines. Some engines do have a flat top piston and the billet head that I make would actually result in reduced performance for these engines.

    I'm certain that there are other engines that will benefit from the correct chamber design that is machined into the billet heads. In summary, the deck height should be close to zero, and the piston should be crowned. The deck height should be checked on the diameter of the piston not the crown. The crown should be above the jug surface.

    Jim
     
  11. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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