PRETTY POWERFUL PUCH PRECISION on China?

Discussion in 'Performance Mods' started by geebt48cc, Mar 2, 2013.

  1. geebt48cc

    geebt48cc Member

    Yes, today it was cold and thought that I would put this really cool VXB 10X14X15 Needle bearing on bike. It's a bit longer than stock 13m, to 15m to kill some of the free play between piston once together. Well not from Germany (like I would like), but it's from Japan. It's a rated at 50,000 RPM. That's pretty close to tops on this engine at WOT, but it still will work.............lol

    So, after I got all of that done, I put the Puch high high compression head on. I didn't use any head gasket. Uno, like Jag told me, it wouldn't give me anymore compression than the milled slant head I took off..........Its about the same now still, BUT!!!!!!!!!!!!! ENGINE sounds better + MUCH,MUCH,MUCH runs cooler in temp too!

    Yeap, you chalked another one up JAG......................but I'll catch you on something yet. lol


    All is good

    Glen PS-I'm a big guy at 6' 6",260, and this is the first needle bearing I've done. It had 800 miles stock, and didn't really show any wear/or play? Around here in SW Va., it very hard to find many flat areas to ride either. THINK about that?
     

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  2. jaguar

    jaguar Well-Known Member

    hey now, we want to see pictures of your engine with the funky looking head!
    Does it run the same? I once modified a stock head to have a squish band and it ran worse. That is because squish bands work by increasing fuel/air turbulence but these small engines already have enough. With that advantage gone the fuel mixture has less opportunity to reach the spark plug on its upward journey from the transfers because the squish band presents a lip to the flowing mixture, diverting fuel from a direct path to the spark plug that is hopefully made up for by swirling the mixture right about the same time the ignition spark happens.
     
  3. geebt48cc

    geebt48cc Member

    Yeah, it really is just about identical to my old milled slant head. BUT, I only was able to ride it just a couple of miles? One thing I really have noticed, is the motor is going to run cooler. It has never had any issues there, but now it has more surface area to cool.

    I'll take a few pictures tomorrow. Jag, after reading so much about this head, I thought for sure that I would need a head gasket or two? Uno, in order for me to get the same performance that I had from stock milled slant, I also am not using any gaskets. I'm going to get the compression gauge on it pretty soon to see.

    Gosh, I don't really think there's much more I can do mod wise to this single engine.............Is there? Jag, I've lost my bag of jumpers for the Jag CDI. It doesn't now have any jumpers at all.(Total of four) So, just wonder if that would help in any way with this head? Stange, because you would think by just looking at the two heads sitting beside each other, that the Puch head, would really be much higher in compression...................but like I said, they really are neck to neck?!
     
  4. jaguar

    jaguar Well-Known Member

    Well it's hard to tell just by seat-o-the-pants which has more compression. Put the gauge on it and then add a gasket if it's 140 or more.
    Most people go w/o any jumpers on the CDI. Have you reversed the wires yet for a hotter spark and longer lasting plug?
    What else can you do to the engine?
    1) stuff the crank and/or unused space between the reed valve and the cylinder
    2) redirect the mixture flow from the transfers more rearward (for more torque)
    3) put lighter wist pin on
    4) make sure the air filter is non-restrictive by testing with it on and with it off (should run the same)
    5) narrow your stinger diameter by using an insert for more down low power. You can make your own insert by cutting out a section of cheap aluminum cookware. Make the final hole 8mm diameter. Make sure there are no leaks anywhere along the pipe.

    Just when I think I have discovered all the tricks of the trade then I discover something else to do. :)
     
  5. geebt48cc

    geebt48cc Member

    Jag, I understand all that you've listed, but #2?? ..............................Also, last night, I took the only base washer off myNGK B6 plug to even add that much more compression.

    These are the bad pictures
     

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  6. jaguar

    jaguar Well-Known Member

    You should paint the head black to keep it from standing out too much.

    Redirecting the transfers is one of the best ways to get more low end power from these engines but nobody does it. (wtf?) That's a head scratcher to me. It's not hard at all to do. Read about it on my site and get back to me with questions.
     
  7. roughrider

    roughrider Member

    Heh. I've hardly discovered any, but I HAVE discovered that these engines are fun to play with.

    And Glen? Whoa dude, that's one tricked out machine! I can tell you just love messing around with your bike.

    As much as I like the simplicity of a big rear sprocket to torque up hills, I'm already thinking of all the mods I'd need to get the same torque and acceleration out a 36 tooth sprocket. But all else being equal, I just need 30% more power, but then I'd have a motor that turned 4,000 at 20mph (my regular cruising speed) instead of 5,000+. Thus, my engine would last longer.

    Best,
    Rick
     
  8. geebt48cc

    geebt48cc Member

    No, Jag, I remember you talking about how any high compression head you've tested has pretty much been equal to milling a stock HT head, compression wise. I tell you, the big reason I got, is do to the higher temps you get when you do mill stock. So, with this Puch head you get so much more surface area for cooling. Gosh, it even looks the part also.

    Question? I've found everything you listed, but I can't find the redirecting the mixture flow to transfers ?

    Thanks big guy..........
     
    Last edited: Mar 4, 2013
  9. jaguar

    jaguar Well-Known Member

    Big I am not. people used to scratch their heads wondering how this skinny person could do so well at motocross.

    Yeah, the stock head can get pretty hot. On my racer engine it got up to 425 degrees on one short test run. at only 130psi and 8300 rpm.

    Click onto the link for "correcting transfer ports".
     
  10. geebt48cc

    geebt48cc Member

    O'yes, I see now. Jag, after you've filled in that portion of intake with JB, there's not and chance of it breaking off with time or temp? I know you've got to get intakes on jug very clean, but still?

    lol, Jag, I bet you really could dominate on motocross, considering your size!
     
    Last edited: Mar 4, 2013
  11. jaguar

    jaguar Well-Known Member

    I have done a few and no problem with any of them. I make sure it is super clean by utilizing my rotary tool to clean the area first. then I make sure the glue occupies part of the top and bottom curve, which is most important for keeping it secure.

    ps- picture this: old American that is skinny with health conditions leaving far far behind the young latinos. needless to say I wasnt popular. One of my last races I had to stop after the first lap to see where everyione was. I let the second guy catch up to me to give him a chance and them left him in the dust. They didnt even invite me to the awards ceremony. Not that I had any good year long placement. I just did it for fun and didnt do all the races so my overall placing wasnt good. People that take plastic trophies serious need some serious mental help.
     
  12. geebt48cc

    geebt48cc Member

    Jag, thoughs trophies still would have bragging rights though?!!!!!!!~
     

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  13. jaguar

    jaguar Well-Known Member

    Im not going to pretend I am pure but I do believe that ego and pride are the natural enemies of our spiritual advancement. I am glad I have no trophies. The whole idea ruins the child-like fun of it all. People get serious and mean and use their motocross status to stand on the heads of others. The way I got into it was I was part of a weekend trail riding group and sometimes we would go to the motocross track after trail riding, on Saturdays. We would practice and after a couple months the organizers asked us if we wanted our own classification to also race Sundays (once a month). We said yes and our enduro class of motocross was born. I have always been extremely shy and I almost didnt race the first time because I didnt want to be observed by so many people. But eventually I got used to it. I tried to use epoxy to patch a gouge that was in my piston and the uneven heating of the piston caused it to bust and ruin the cylinder on my KDX 200. The sleeve was then custom made for it but made out of soft metal that would only last me 6 months. So I decided to turn lemons into lemonade and started experimenting with porting. I eventually settled on a good setup which gave really good mid-range power which allowed me to get the holeshot almost every time. That was the beginning of my current love of 2 stroke discovery and experimentation.
     
  14. geebt48cc

    geebt48cc Member

    Jag, when you did race some, I'm sure that people did swamp you to gain any imformation on what mods you made. Amen on the ego trips, because testosterone runs wild I'm sure. Jag, I know 8mm diameter, but what is best length of ending stinger on exhaust?
     
  15. jaguar

    jaguar Well-Known Member

    Geebt, look at the top of your piston and see if there is any residue in a pattern which would indicate whether or not the intake charge flow is correctly rearward or not. If there is a pattern then take a picture of it and tell me which is the exhaust port side.
     
  16. jaguar

    jaguar Well-Known Member

    No, they were too jealous (due to ego) to admit I knew anything and to ask my help.

    If you input engine size and peak rpm into my Excel file then it gives you max and minimum stinger diameters for 3 different lengths.
     
  17. roughrider

    roughrider Member

    It takes wisdom to know one's own ignorance, so para-sayeth Socrates. Then, to ask for help, requires humility, yet, I would add, self-confidence.

    Unfortunately, sometimes, asking for advice will make the other person think they are somehow superior, and they will then try and act the lord and master in all things, all the time. So--sometimes--it is wise NOT to ask such a person's advice.

    Not talking about you, Jag. Just sayin' that many people have had this experience, so it can make them shy.
     
  18. jaguar

    jaguar Well-Known Member

    Every time I start to get a big head then comes along a situation that makes me feel like I'm still just beginning to learn.
     
  19. geebt48cc

    geebt48cc Member

    Puch paint

    Jag, this isn't bad.................Is it?
     

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  20. jaguar

    jaguar Well-Known Member

    What's bad is you running out of room around your engine. Looks like the motobike of a mad scientist! ha!
     
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