Kymco ZX50

[zombie]

Once it's aoll dne it willl bee toooocool

[Shaka]

Thanks Sid!  Kinda weird, but I hope you've had a good weekend!  
I sure hope so Zombie!

[sidthesloth]

Ahh, well, started dayshift on friday but at least it is only five days.

[sidthesloth]

G'Day all, I managed to pick up a piece of aluminium today but I could only get 1.6mm or 3mm, so I took the 3. BUT, having been reading The Two Stroke Tuner's Handbook I came across the part about the ports. In this section he suggests that rather than trying to machine the ports it is better to notch the piston to try the adjustment. Do you reckon this might be worth a try, or should I just go ahead with the spacer idea?

[zombie]

I appears that your ports are too far out to take that much off the piston. They are all consistent too. That make for raising the jug as the better option in my opinion. If you find you still need 1mm or so for the exhaust it would be a good idea to remove a little there. That will also help cool the piston in front of the port if you can channel the mod into a V shape from the center. soooo I would keep moving along w/ the spacer.

[Shaka]

Sid, I think Zombie is correct about notching the piston.  I think this is more for trying to match up when one port is too low.  I think he specifically uses the exhaust port in the example.  I worked with my own portings yesterday and found some interesting correlations.  I'll take another look at yours this evening and let you know what thickness spacer to use.

[sidthesloth]

Yeah, I thought so too, was just a thought. Reading that book there are a lot of ideas in there.

[Shaka]

Sid, I ran your port map back through the software.  It is showing the bottom of the transfer ports are the highest.  To bring the piston to the bottom of those ports at BDC you will need to add an additional 2.25mm of base gasket to the already 1.05mm gasket that was in place when you took the deck height measurement of 0.35mm.  With that added gasket the exhaust port will still be covered by 2mm and the boost by 3.6mm by the piston.  That should be a good compromise as you don't want the transfers to be above the piston at BDC.  This means that your deck height would then be 2.6mm.  We need to know the thickness of the head gasket you will be using as well as the amount of recess in the squish area of the head to determine exactly how much material need to be removed from the head to achieve a squish of about 0.8mm.

[sidthesloth]

I got 3mm plate for spacer, head recess was  0.78mm head gasket is 0.5mm. when I cut the spacer I will add gasket to bring the trans. ports to the piston top and take some more measurements. I haven't remeasured yet as I am still using the scoot. I get a couple of days off now so will try to cut the spacer tonight.

[zombie]

Here that shaka! He's still riding the scoot!I'm Impressed!

[sidthesloth]

I know, I know, I shouldn't ride the scoot until I get it sorted properly, but its there to use and so I do. Bad policy I know but I never claimed to be good. lol. :-)

[Shaka]

Whatever!  If it runs, run it!  Unless it's lean!   How's it been running Sid?

[sidthesloth]

Not too good, the weather has cooled a quite a bit but I don't think that is the problem. It will run off the clock at about 1/4 ~ 1/3 throttle but try to open anywhere past half and it just bogs, I think it is to do with altering the jug height, once we get it set right and get the top trimmed I should be able to have another go at the carby. I started cutting the spacer tonight, drilled lots of holes and used a small hacksaw. Lots of cutting, lots of filing and lots of patience. Another hour or so tomorrow and it should be done.

[sidthesloth]

G'Day All, I have finally done the spacer and am about to pull the scoot apart (not for the first time) and insert the spacer and see where we go from there. I don't think I have done too bad a job of it, though not perfect it should do the job.

[zombie]

This is one time that I really,really want to say F' Yeah it looks good! Sid... I commend you! Too bad Ausi. is an island or I'd be scootin' as fast as I could to shake your hand. If you have to trim some mm. off the spacer it is an easy task for a fella of your skills. Can you hear me applauding you... Just did!