HELP UPGRADING

[maddog21]

Thanks zombie about how fast do you guess my top end speed will be i have 11.5 to 1 gears airsal 70cc lc top end 6 gram rollers unrestricted cdi and technigas next r chrome pipe still orderi.g parts i will order those springs and contra and brass weights tomorrow thanks again

[zombie]

Your stall point is the rear gears. You will easily reach 60, and do it pretty quickly but at 11:1 you will be at or about 8500-9k rpm.

I would contact Josh at  http://www.thescootergarage.com

Tell him I sent ya, and ask what he has for a better gear ratio. You will be able to reach 65+ with a 7-8:1 ratio, and cruise at 60 all day around 7500-8k rpm.

These are tough ass engines, and they can/do take it.

[maddog21]

Thanks zombie will they handle 10k or not good for them i run my cobra 9k it is bone stock just pipe

[maddog21]

Why does it say you are banned and not trusted by admin lol

[zombie]

My ZX is dialed in at 9.5 - 10.5k. It runs 65-70MPH all day (7.3:1 gears).
From 10.5k the Ign timing (HPI Programable CDI) slopes to 3* BTDC at 13.8k, and 82 MPH. There is no real power in this over rev but it keeps the bike humming.

These engines can handle a sport kit w/ no problems.

LOL the Avatar... I found that, and banned myself. Someone had too!

[maddog21]

Where did you get that cdi

[zombie]

From Horse Power Ignition in Belgium,  http://www.hpi.be

I bought a complete ignition system from them for just under 600.00 US.
I think just the CDI sells for 245.00, and I'm not sure but I remember the interface "dongle" is 45.00 (computer interface).

I have a second HPI/CDI that will fire off an OEM pulsar coil, and work w/ any ignition coil. It's brand new, and only been test fired for a fair price if you are interested.

Benji from Treatland sells a sh** load of them if you want more info. Or you can Email HPI. They are great guys,although I did have some software issues that took forever to straighten out. It's a smack up, does what you want it to do set up. I never could have tuned my bike correctly w/o it.
Our OEM or "performance" CDI's are like buying a carb that can not accept new jets. You can never get to real power or over rev without tweaking the Ign curve.

For a daily driver it is over kill. But for a wannabee race bike (70mph +) it's the real deal.

[maddog21]

How much differance would it make on my super 9 and how much do you want and its just cdi thats it right?

[zombie]

How much differance would it make on my super 9 and how much do you want and its just cdi thats it right?

With a mild sport kit, and all the goodies lets say you get 65, and approach 70 on a good day. Also lets say it takes 10 seconds to reach that speed.

What the Ign. will do is give you a couple seconds off the ET maybe 8 seconds now, and if you tune the curve correctly you can increase your top rpm, and speed by maybe 2-3 MPH, and another 1k rpm above the factory red line.

Read up on it before you get antsy. The software is free, and available at HPI's web site. It's called "Tune Box". The dongle can be ordered thru Treatland...  https://www.treatland.tv/new-puch-peugeot-motobecane-vespa-moped-parts-s/88.htm

If you like what you see I'll sell it for 100.00, and you pay shipping. I can pre program a base line curve into it for you, and you will be able to plug it in to any computer, and see where it is set. You can also modify that according to your needs.

It's all not gravy tho. Setting too much advance at any given point leads to destructive pre-detonation, and blown piston domes.
You have to have an experienced ear for your engine or an Exhaust gas Temp. gauge to know what is happening in the cylinder.
 I just happen to have another brand new EGT too. That one has no sensor probe (I bought it as a back up to mine) but they are readily available on FleaBay for 20 bucks.
If your interested I'll throw in the gauge for 15 bucks. (cost 25+ new).

Beyond that... I have some Presa Canarios for sale too. Maybe an old fridge...

[maddog21]

Lol i will look into it thanks i will let you know i appriciate your help i want to make this thing fast for scooter

[maddog21]

I looked didnt find anythung called tunebox and that is for the super 9 i didnt see anything there for super9

[zombie]

And you wont... It's a universal kit, and the software is for all their cdi's

http://www.hpi.be/068.php?cyl=1  full kit

http://www.hpi.be/downloads.php  scroll down to "Downloads"

I checked what I have, and I also have an inner rotor. Not the whole stator kit but if you price it all out you will save around 200.00, if you want my stuff.
I'm really just sitting on it cause it is single purpose. You have to want to get into custom tuning or it is a HUGE waste.

[maddog21]

I want to make it a beast but i would need some advice to get started but i am a mechanic so im not stupid but never done anything like that to.a scooter

[zombie]

Then you understand ignition curves.
All of the 50 - 150 cc Kymco scooters have the same curve. They begin at 24* BTDC, and straight line to 0* at 9k. Thats the sole reason none of them make power after approx 7k. = 3*

I set my initial timing to 32* BTDC, and sloped it to 22* at 8.5k.
When the pipe, and cylinder come together at 9.5 the timing is 20*. I keep it there till 10.5, and slope it straight down to 3* BTDC at 14k.

I kept it high in  beginning /trial runs but found bad Pre det the both in the power band, and in the over rev ranges.
The EGT also confirmed this with dropping exhaust temp. (meaning the piston was holding the heat, and the timing was too far advanced)
Every 5* I dropped the timing was showing a 50* rise in temp in the pipe.

I followed that to achieve a steady 950*f in the pipe at 6" from the header.
Like I said you can do this by ear but the gauge really helps settle any doubts, and second guessing.

On the "Kymco Links" thread, 2nd page 1/2 way down is a link to a couple of books .
Two stroke tuning by Gramm Bell, is the better of the two but they are both good.
I read cover to cover several times to get all this straight in my head.
I have owned 2t bikes since I was 13, and learned quite a lot. Those books explained to me what I knew, and what made the things I knew happen.

Since there are so few cylinder choices for the S 9... You might want to consider some custom porting of whatever cylinder you wind up with.

Rule of thumb... Taller ports (closer to the head) make more power but narrow the usable power band, and raises the rpm that band kicks in at. Perfect for drag bikes.

Lowering the ports makes less power but allows for a wider band, and lower cruise rpm.

Check out the books.

[maddog21]

Thanks zombie you know your stuff i appriciate your advise and i want those parts you have so what else would i need to go with it and how will we do the deal i live indiana
I think it will be a beast with that cdi so tell me exactly what else i would need to make it right for my super9 lc snd how high are these safe to rev do you think with stock crank and will my next r pipe be good enough thanks alot for your infirmation it will help me alot. I advanced timing on my zuma myself by longating the holes it made big differance i waas surprised in the differance is it easy to do on the kymco to?