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Thanks Slinger', I've just noticed the confusion surrounding the "Black Art" of tuning popping up in the forum a bit lately.

Always happy to help

Josh.

In regards to the jetting/adjusting questions, there are a few things that probably need to be pointed out for all the newer members (Like me!) Although I don't always have all the answers, however I'm fairly well read, and am not afraid to research things, ask questions, and give things a go myself.

ANY intake/exhaust mods (eg bigger/smaller exhaust, pod filter, removing collett in airbox, and so on) will require:
1. A replacement jet (high speed jet, not the idle jet unless absolutely necessary).
2. Adjustment of the air/fuel mixture.

Here's how it works:

The Jet controls the flow rate of the fuel, in conjunction with the needle that runs through it.
The bigger the number on the jet, the more fuel it will flow.
If you increase the flow of air through the engine, you MUST increase the amount of fuel going in to it, otherwise the engine will run "Lean" ie; Not enough fuel mixed in with the air, and the engine will run very hot, possibly burning a hole in the piston (you don.t want this).
If the jet is too big, then it's not nearly as dramatic, except the engine will run too "Rich" (too much fuel mixed in with the air), resulting in loss of power, fouling of the sparkplug, and an engine that will run like crap.
Once you've put a bigger jet in, it's time to adjust the air/fuel mixture.

Now remember this: The mixture screw adjusts the amount of air coming in via a very small pilot hole to create a venturi effect. It does NOT adjust the flow of fuel. That is determined by the relationship between the Main (High-speed) Jet and the tapered needle that runs through.

Tighten (do-up) the mixture screw, you let in less air and a leaner mixture will result.
Loosen (undo) the mixture screw, you let in more air and the mixture will become richer.

A perfect mixture (air/fuel ratio) is called Stoichiometric (commonly called Stoich) and is an air/fuel ratio (AFR) of 14.7:1 ie 14 parts air to 1 part fuel, though this is damn near impossible to achieve.

Tuning any engine without an oxygen sensor/exhaust-gas analysis machine is damn hard, with most tuners relying on three things:
1. "Feel" of the engine eg smoothness, pickup (acceleration), sound, vibration etc
2. Temperature ie Leaner mixtures = hotter engine temps, while Richer mixtures = cool running's.
3. Spark-Plug Colour (Ok, Color for you USA scooter-nuts)

For more info on the correct colour of the carbon build-up on your spark-plug, i'm pretty sure I saw a link on here somewhere for an excellent guide....

Just remember, adjusting the mixture screw and riding around for 5 minutes at full throttle will NOT give you an accurate colour-change on your spark-plug. It takes a couple of hundred Kilometres and a wide range of engine load/s rev-ranges, stops, starts, start-ups and shut downs to accurately guage a PROPER colour-change on your spark-plug.

Happy Tuning,

Josh.

Hey guys.

Finally got time to install my new Keihin CVK 24mm Carb in the Like 50 4T!

Well.... sort of.

Everything bolted up better than I thought, with the new carb even fitting into the original inlet hose from the airbox.

The problem is, that I left a sneaky vacuum hose off the manifold (didn't see it hiding!), and proceeded to try and start the scoot.
After 20 minutes of cranking and pouring fuel manually into the bucket, I gave up for the night.

The next day I tried again. I eventually found the elusive vacuum line and connected it, and pulled the top off the carb to pour some fuel in.

When I went to put the slide back in the bucket, I noticed that the rubber diaphragm had stretched so that it won't fit into the groove correctly, and threfore won't provide a good enough seal for vacuum.

WTF? I thought thhis type of rubber would be fuel-proof....

Any ideas?

Josh.

Hey guys,

I got my 1,000 Km Service done today, pretty reasonable @ $101.00.

The Like 50 4T is much smoother, accelerates slightly better and generally feels like it's got more torque to play with in the mid-range.

My question to you all is what kind of spark plugs do you prefer to use, and is there any point to using something like an NGK Iridium plug?

Your thoughts........

Josh

I see 

Note in bright sunlight, it's actually a deep blue metal-flake finish though, right?  At least the "black" Like 200i our shop just got recently is this deep, metallic blue, I should say. Maybe it's different in other markets.
.

Yeah, my girl was the first to notice that it was actually black with a blue metallic flake through it - like a week or two after I bought it!

Very subtle it is.

Josh.

..same engine and tranny as the a50...

So would the exhaust mounting points be the same between the two?

Like, can I bolt an a50 exhaust on my Like50?

I got my sexy new Leo Vince Scoot SP3 Exhaust in yesterday...... I ended up buying one direct from Italy to fit a Suzuki AP50 Address, as it looked like the closest fit to mine.
Within a matter of minutes of the courier delivering my box of goodies, I was under the scoot doing a trial-fit.
The mounts should be ok, but the Flange that butts up to the head needs to have the weld ground off, the flange rotated about 140 degrees, and re-welded to the bolts will line up 
I was so hoping it would be a bolt-on.
Oh well... I have to attack the restrictive cone on the inside of the inlet with a Dremel anyway.... There's no way in hell that's staying there!

Josh.

what up jb..... thats a pretty cool scoot right there....i like that, no absolutely nothing on a 4t tho....lmao...    i have a 04 zx50.... THANKS TO WORD, i FINALLY have a pic of it in my thread(tech)...

By the sounds of things, that ZX of yours hauls ass! I got just over 90 km/hr out of my Like on a slight downhill last night.
Still the stock Carb & Exhaust....., just a DE-Restricted Variator Bush!

WTF?