New variator aaaannddd issues arise....

[streido]

Glad to hear that. Hope for you, that its the right one

96 was useable but just too rich, 94 was better but gave a little backfire and hesitation and plug read a little too rich, 88 was too lean so i think the 92 is almost perfect. It runs well on it anyway so ill do a proper chop tomorrow to be sure. Think its easier now i have the Leo fitted rather than the stock exhaust, was a nightmare before but runs better now. Find out for sure tomorrow.

[blue]

with all my luck im better off with a briggs and stratten on my scoot.

[wordslinger]

How would you tune a CVT, so his rpm wouldn't rise after hitting max gearing?


..trial and error...

[streido]

with all my luck im better off with a briggs and stratten on my scoot.

Or pedals 

Ive had a nightmare getting mine just right, think its been 2-3months on and off ive been swapping jets and changing plugs to get it good. Better that than running lean tho i suppose.

[baddi]

How would you tune a CVT, so his rpm wouldn't rise after hitting max gearing?


..trial and error...

The only way i could find would be to tune the CVT to get the engine at its max RPM while upgearing or to install an extremely strong contraspring, that steals so much torque from the engine, that either cant hit max gearing or that it havent got any more power to increase the rpm after hitting max gearing.

I'll still say that he should either let go of the throttle when he have hit the max gearing or that he should increase the final gearing after the CVT, so that he will have more speed, go longer per liter of fuel and not have enough power to hit max gearing and therefore not enough to hit max rpm, and his CDI wont stop cutting the spark and throwing fuel to the exhaust, as it does now.

[zombie]

That makes perfect sense.
Using a "race contra spring will hold back top rpm while giving great low end.
Using up gears will give a better top end, and reduce take off-mid range.
Like always it comes down to 'Balance"

[baddi]

That makes perfect sense.
Using a "race contra spring will hold back top rpm while giving great low end.
Using up gears will give a better top end, and reduce take off-mid range.
Like always it comes down to 'Balance"

I'm just saying that to Word, as he here say that tuning the CVT could prevent him from hitting max rpm after his vario is fully geared out, which can only be done by disturbing the balance in the CVT alot, as the CVT tuning has none effect from the point that the vario is in highest gear.

So if he keeps his throttle turned after hitting max gearing in the CVT, his RPM will rise

..true...then more cvt tuning is needed...so that cant happen...

For all the time i've been reading and sometimes posting here, i've looked at Word as one of the wise men of this forum, so it didn't really match when he said that CVT tuning could prevent this. :p

[zombie]

Slinger, and I had just finished talking about how the CVT controls the engine/rpm's, and I think he got carried away on that one. Using the cvt to tune the power band is what we were really talking about. Max rpm's are a different issue.
The only way to efficiently control rpm's is thru Ign. timing, or a rev limiter. It's too bad no one has figured a way to re program the OEM cdi's.

[baddi]

Slinger, and I had just finished talking about how the CVT controls the engine/rpm's, and I think he got carried away on that one. Using the cvt to tune the power band is what we were really talking about. Max rpm's are a different issue.
The only way to efficiently control rpm's is thru Ign. timing, or a rev limiter. It's too bad no one has figured a way to re program the OEM cdi's.

Okay, misunderstandings happen.
But what i were saying to the OP was that his popping sound might come from unburned fuel getting thrown into the exhaust as he hits the rev limiter. After all, he has mounted a bigger cylinder, so he certainly has the power to do this
The reason why you cant reprogram a CDI is that it either uses ROM (Read Only Memory) or are not digital at all but just uses analog circuts to control the ignition advance and such. If it's analog, it should be possible to change a component (problably just a resistance or a couple of them) to make the ignition curve either steeper or flatter, but it is not really deeply possible to tune the ignition, this way.
If the CDI is digital (which i guess, depending on this), it will be using ROM, which is like if you carve something in stone. I guess that you could be able to reprogram it the same way it was first programmed, but i dont know how this is done, only that the components in the CDI doenst have a "writer" so you can over- or rewrite information without opening the chip and having special machienery.

I guess one of the reasons why they use either analog or ROM in CDIs are that these technologies are much less liely to get tempered with and besides that, will endure hot/cold weather, much use and many years better than the use of a harddrive and RAM (Random Access Memory) would do.

(Trust me, im an engineer)

Btw, OP, you never said if you are using a cut standart CDI, or if you have fitted a CDI compleately without RPM limitation.

[zombie]

Very nice! I am guessing you are correct about the unburnt fuel. It MAY be from a rev limiter missing the "beat". It is subjective by ear. I find Sharp/High pitched POPPING to be lean, and a Low pitched pop to be flooding. The sharper the sound the more likely it is to be lean. Like a fire cracker. If it sounds like hitting a pillow it is more likely flooding/mis fires.
Nice posts Baddi! You know your stuff for sure!!!

[baddi]

Very nice! I am guessing you are correct about the unburnt fuel. It MAY be from a rev limiter missing the "beat". It is subjective by ear. I find Sharp/High pitched POPPING to be lean, and a Low pitched pop to be flooding. The sharper the sound the more likely it is to be lean. Like a fire cracker. If it sounds like hitting a pillow it is more likely flooding/mis fires.
Nice posts Baddi! You know your stuff for sure!!!

Well thank you very much, i'm working hard to learn more too.
It's the first time in quite a while i've heard this, so Damn, that last comment just made me happier than hash!

I can't really explain how i can hear the diffrence on the sounds, but hitting the rev limiter sounds to me like flooding big time, so perhaps this is what he is experiencing. We wont know until he writes back about the CDI and if the popping is when he is at high speed or what. :p

By the way, Zombie, arent you a mechanic or something?

[zombie]

Marine engines by trade... I do them all. Outboards to inboard diesel. Plus I have had dirt bikes/street bikes/scooters/go carts/street rods/race boats/ect for 40 of my 53 years. I've made almost every mistake that can be made. So now I spend my free time trying to help others avoid all the hassle. I still blow alot of my own stuff up too. One more hp... I KNOW I can get One more hp!

[baddi]

Marine engines by trade... I do them all. Outboards to inboard diesel. Plus I have had dirt bikes/street bikes/scooters/go carts/street rods/race boats/ect for 40 of my 53 years. I've made almost every mistake that can be made. So now I spend my free time trying to help others avoid all the hassle. I still blow alot of my own stuff up too. One more hp... I KNOW I can get One more hp!

Sounds like you have hell of alot experience
But do you turbocharge and NO2 inject the engines without adding more fuel since they can blow up, or what do you do to them? :O

[zombie]

The only turbo engines I mess with anymore are diesel. I never liked the idea of gas/turbos... You waste a TON of fuel that could be better used thru porting. Blowers on the other hand are are whole nuther deal. I Like blowers... Nos is cool/fun. I never tried a dry system. I have done a sh** load of wet systems on bikes/cars/boats. Believe it or not you can get similar results with water injection... water makes aLOT of compression. With all of the methods to increase HP/Torque you Have to dump in sh** loads of fuel. Keeping the air cool, and the fuel hot are really the keys. Highest compression wins.

[baddi]

The only turbo engines I mess with anymore are diesel. I never liked the idea of gas/turbos... You waste a TON of fuel that could be better used thru porting. Blowers on the other hand are are whole nuther deal. I Like blowers... Nos is cool/fun. I never tried a dry system. I have done a sh** load of wet systems on bikes/cars/boats. Believe it or not you can get similar results with water injection... water makes aLOT of compression. With all of the methods to increase HP/Torque you Have to dump in sh** loads of fuel. Keeping the air cool, and the fuel hot are really the keys. Highest compression wins.

Wait what? Turbos not being effícient?
Are we talking 2- or 4-strokes, because at 4-strokes, this seems like something i should know before i start saving money for the turbo