ZX50 Crankcase Tuning

[sidthesloth]

Alright, I have bitten the bullet and ripped the engine out with a view to increase the inlet tract. I have never done this before, so I will be learning as I go, and hope to hell I don't muff it.
I will include some pics as I go. I have a couple of questions if anyone is able to help, I would really appreciate. Looking at one of the pics you will see where I have marked the aux. port. The existing one in the case is tiny, where the one on my cylinder is massive by comparison. How far can I go with this, without causing any problems? Or can I just go as far as I like while leaving a reasonable wall thickness.
Also, in the same pic, you can see two holes which I assume the fuel is forced through, to go to the transfer ports, should I increase these as well? The reason for doing this is that I have put on an 82cc cylinder kit, along with a 24mm carb and inlet to suit, at around half to three quarter throttle there is no more acceleration, only an increase in noise.
Any input welcome.

[Rianna]

You can do, sid...Good luck!!!

[wordslinger]

...where th' hell's zombie...........

[Hoolander2]

You mean those two round holes in the bottom of the transfers?  I think they're for letting some of the fuel/oil mix get to the crank bearings for lubrication.  Don't know about other questions, sorry.

[Hoolander2]

And I wouldn't increase or change them in any way.  Increasing them, I believe, would decrease amt of mix going up the transfers. 

[sidthesloth]

Yes, thankyou Hoolander, I see that now. See, always learning.

[art]

  Your in over my head sid  Just a thought though. I believe this is about where I was at on my people 50 (before problems) I felt my real hold up was gearing. Your making noise but no more power to the ground because the tranny has hit it's peak.

[sidthesloth]

No, I don't think so art, I have now got the tranny at what should get her going. But right the way through setting up this cylinder, it has had nothing over half to three quarter throttle. I don't know if this is going to do any good, but the only way to find out is try.
I will put in a couple pics of where I am at so far.
The boost port has got me worried because I don't know whether to cut right the way down or not.

[sidthesloth]

This one is from outside the inlet with one opened up.

[sidthesloth]

I will try to put two pics on here, one from inside and one from outside. This is the inlet windows opened.

[Rianna]

Wow, sid, you have been busy. I see what you mean by "all in pieces" now.

[Hoolander2]

I'd go easy on that boost port on this first go round.  Open up too many ccs below and you're not gonna force enough mix up.  Oh well, can always fill back in with weld. 

[Hoolander2]

Does the boost port have it's own reed?

[sidthesloth]

G'day Hoolander, I took the safe option and opened the channel above the crank and left the casting near the crank as was. There is no reed there. Will put up pics when I get home.

[sidthesloth]

Here are the pics of the case after cutting out the boost port. The tabs you see at the bottom of the channel are the ones that caused me some concern. In the interests of playing it safe I left them as they were. I think this will utilise the carby a lot better than it was before.