my zx50 issues

[Shaka]

..itsa stock engine he tuning...

I know, the principles are the same no matter what engine you are tuning.  I Jennings book, one of the first chapters talks about tuning a stock cylinder and first "bringing it up to factory spec"  as there are always slight imperfections in the manufacturing process.

[wordslinger]

...i need me a 2-stroke....

[thebatman]

hey shaka, sorry i missed you....   ok, sounds FAIRLY easy, but the "cyl tunnels"?? is that the "over hang" on the cyl that slides into case first??   match it??? what grind all overhang off???     im so close to 50+, damitt man!!   i know you think im crazy saying i had reached 52mph wit this stock ass scoot... i do believe that 1500 helped, seems to have dropped a tad wit the 1000.    i did print the jennings book, hadnt ever seen the other.    was hoping that cage would get me there with other slight mods.        well sid, how did you even GET the numbers?? those strange formulas on jennings book??   how you check, my calipers dont fit everywhere...

[sidthesloth]

Hey batman, don't grind off those guides. I know what you mean about the calipers don't fit, it would be so much easier if they did. When I read Jenning's book I didn't understand a lot of it, the maths will have me bamboozled every time, but it gave me a better understanding of how the engine works which helps with trying to improve the engine, when Shaka said about matching the cylinder to the case I think he meant grinding the crankcase to suit the cylinder so that the port tunnels line up and give a better flow.

[Shaka]

What Sid said, match up the port tunnels, you don't grind the cylinder skirt off!  To get the measurements you have to make a port map.  You do that by rolling up a piece of paper and putting it inside the cylinder.  Then you make a transfer rubbing with a pencil to outline where the ports are.  You then remove the paper and take the measurements off the paper.  Here's a good starting point for learing about cylinder porting:  http://scooterinvasion.net/forum/viewtopic.php?t=708

[thebatman]

so does everybody use the ngk br8sha spark plug?? wit all getting indexed  i used bosch in my car, why couldnt i use those, they are good plugs, or sumthin... bosch has the 4 way electrodes too, wouldnt that help on 2t?? burn more

[Shaka]

I currently am using the Champion equivalent BR9HSA plug just because that is what I got for plug chops when I bought all they had!  I've just been running through those and then I am going to try the iridium.  I think it is a BR9HIX?  You will run the BR8 though in your stock motor.  I had to go with a cooler plug with the aluminum cylinder.  I'm not sure about fitting the plugs with multiple electrodes.

[thebatman]

i cant never get to the local shop for sum plugs but napa is down the rd..  seems like those splitfire type plugs would be ok...   i have heard that word iridium...   maybe they could match it

[thebatman]

well i tried going over to scooterinvasion....logged in, read sum stuff, went to post, KEEPS telling me to log in OVER AND OVER!!  BUT at the bottom of page, im right there.... guess im getting MANY omens not to even touch scoot again, cuz since cage wont help, why bother getting one of those too?.. was hoping to get a laymans terms explanation on that... if i remember my jug, theres ONE HOLE: exhaust.. not the 6 hole drawings i saw

[Shaka]

You may not have had your account activated by the moderator yet, so you can log in, but not post yet.  Your cylinder is the same as all the ones you see on there.  It has an exhaust port, which is the biggest and leads directly out the side of the cylinder.  The other intake ports are routed out the bottom through the transfer tunnels into the bottom end.  You have to remove the jug  to see the transfer tunnels, they lead out the bottom.  The new reed cage may help a little, but won't make a dramatic improvement without changing the manifold and carb as well.  If you want to keep the stock carb, it has got to be a slight improvement.  I can't speak from experience on that one, as I changed my carb and ran it with the stock cage and manifold; then changed the cage and manifold after I realized how restrictive the stock ones are.

[thebatman]

yeah, id like a bigger carb but running stock jug, surely i couldnt go up much... figure about a 17mm?     this gets real frustrating on my end..i love to see the work/any work being done so i can really learn how to do it myself

[wordslinger]

well i tried going over to scooterinvasion....logged in, read sum stuff,

..takes a minute to get all their settings squared away...hang in there...

[zombie]

 cant never get to the local shop for sum plugs but napa is down the rd..  seems like those splitfire type plugs would be ok...   i have heard that word iridium...   maybe they could match it    Who Lopvew ya daddy! You can go to 28mm on  the carb w/ no trouble. How much do you want to spend. Fix the bits first,

[thebatman]

theres no way i can put a 28mm on a stock oem jug... thats like puttin a double pumper on a go cart??      oko carbs are reasonable, but i know...delorto, arreche...      what bits?

[wordslinger]

.....the bits ..you know......all those BITS!!