Riding on a cap instead of battery?

why exactly would you want to? a battery is more reliable and able to store energy for a much longer period of time and you wouldnt have to kickstart it at all

On these old topics there are a few things that they neglected to mention. A battery during WOT gets fully charged over a certain time. After this time, the voltage regulator has to drop ALL current/voltage, just like it would when there was NO battery connected. So in other words, it really does NOT matter if a fully charged battery is connected or not.

And there's another thing I question, which I haven't found any decent answers on, is that the voltage regulator dumps excess energy to the ground, to regulate the voltage. That may be true, however, on my scooter, the stator seems to respond to heavy load, or no load at all!
So it's not like the motor is at a constant ballast, but rather a fluctuating ballast depending on the electrical load on the bike.

I'd say, try it for yourself! Install a heater coil (or resistor) on one of the 12V wires and the ground, and drive around, and see if your MPG's and top speed are affected or not!

Like usual, scootnwinn, there is no need for your sarcasm, it may be left behind.
I'm not here to ask questions to people who have no opinion, I prefer to listen to people who DO have an opinion about the topic I'm asking about.

And, no, a stator only charges a battery in tiny amounts, several times a second. At those rates, a cap would work almost identical to a battery.
I don't know what kind of caps you had in mind, but I assure you I'm not talking about a cap you managed to get from a scrapped radio.
I'm taling about between 1/4 to 3Farad caps; they have plenty of capacity to run a bike (theoretically), and more... They just don't have the capacity to keep feeding the light bulbs when someone forgot their key in the ignition, nor do they have the capacity to engage the starter.

Next time, when you don't understand something, it's much nicer to ask, rather than to ridicule! It makes you seem very... well.. low class!

I expressed my opinion sarcastically because well I enjoy it. Acting like you know everything and asking questions constantly showing you have a misunderstanding of the fundamental principals that you are in other threads presenting yourself as an authority on makes you seem very... well... ignorant.

I do fairly well and actually manage to contain my snide remarks on about 70% of the stuff you post and I assure you I work daily to be classier so that I might be accepted by the the entire internet at some point.

I normally answer your question clearly as I did above. You infer however that your idea is right regardless of what anyone may say to the contrary.

So seriously give it a try maybe your on to something.

Sarcasm will always be get used to it

We have thought of this and I've even tried it for a short period of time myself. Being an engineer it was just out of curiosity. It's a bad idea though.

It's been retread and comes up every now and then. But the jist of it is it puts undue strain on the electrical system. When you have such a low internal resistance such as with a capacitor it causes current spikes in the electrical system causing the elements such as the stator and voltage regulator to needlessly heat up. I can explain further with time constants and peak currents and I^2*R losses but I don't know how well versed you are in electrical engineering theory. But when I did it, the voltage regulator was unable to control the voltage reliably and at high RPM's I was getting too high a voltage on the output, averaging 16-17 volts and the regulator got pretty hot.

The regulator was simply not designed to go in a low resistance capacitor. A capacitor does not behave exactly like a battery and isn't a substitute for one. Also the kick starter was not meant to be used as the primary start method, it's for backup only. The teeth will round off pretty quickly and eventually you won't be able to start it.

He is curious and looking for more answers isn't that what discussion forums are for?
Apparently some here can and have tried this out of curiosity but he can't?
If everyone was experienced and an expert this forum would be boring instead of the rude place some of you seem to prefer.
Thank you hank for maintaining your politeness and decorum regardless of your views, wish others could do the same.

Curious, yes. Looking for answers? Perhaps. But he pretends to know things and offer advice for which he has little knowledge. I am not referring to this thread alone, but to the hundreds of others where he has tried to come off as being an 'expert'. When he does ask questions, more often than not, he challenges every answer.



When did I ever say he couldnt try it himself? Don't put words in my mouth.

i honestly do not think that i was being rude i just couldn't understand why even from a theoretical stand point that it was a viable option.

this is a forum and as such everyone types and it is hard to read peoples attitudes and emotions through words so i do not take anything too seriously online

i am just commenting on the kickstarters... i have had a dead bat for over 6 months in my scoot, always kick starting is, and so far there has been no failure at all ( i have made sure to get the bolt torqued down good before i started using it but that is all! )

Thanks guys for your support!
I'm asking a lot of questions, and have a lot of ideas.
But just like we had a thread a while ago, of someone who thought he could improve his bike, by putting a bigger muffler on it, I explained what I have learned from this forum, and did not ridicule him for not knowing; neither did I judge him to be stupid, or treat him with sarcasm.
I think there's no excuse for treating people bad, not on a single forum, neither will you in real life!

I know, the forum is more hidden, and you can vent your frustrations, but if you did it in real life, you might end up with someone's fist in your face, and a bleeding nose if you're not careful.

I also admire Hank's professionalism in all of this, and when I look at people making fun of others, I just think that I was there as well, about 10 years ago.
Perhaps in 10 years those guys will mature, and start getting bored of laughing at someone else.
After all, they do evil to me, they probably do it to others as well. It's only going to end up returning to them.

There is a difference I don't think you're understanding how the charging system works. On 50cc scooters which use only half wave rectification, power pulses are particularly troublesome, and the average current ends up having higher peaks. Lower internal resistance in the battery and the power peaks go even higher even though average current stays the same. Since average current will stay the same the regulator is bearing the brunt of keeping the average current as stable as possible so it ends up sending those higher peaks to ground. That's how excess energy is absorbed in the system it's sent to ground and the power dissipated as heat by the regulator. But it's not just the regulator, there's internal resistance in the stator getting heated up. And once the resistance of a battery is eliminated the regulator is forced to dissipate too much power especially at higher RPM's thus voltage starts rising beyond the ability of the regulator to regulate which is why voltage can get too high at high RPM's those high current peaks are just too high for the regulator.

And you already made my point with lower internal resistance the capacitor absorbs the current faster regardless of voltage, it's the voltage difference over time that matters, which means with the same average current you get higher peaks, higher peaks means more heat in the system because of I^2*R losses.

Those peaks really do have a pronounced effect on the heat the regulator produces. If you don't believe me hook up a 1 farad capacitor to your scooter. I've done this already. Ride it around for 5 miles and then check on the temperature of you regulator if it hasn't burned out by then it will over time.

You're actually better off just running no battery than a capacitor, most scooters that do this just run a ballast resistor. Saves weight and saves money.

I'm sorry to disagree, and without any disrespect, I just would like to share my opinion about this,
but for me, there's no reason to believe that the voltage would rise higher with a cap, than with a battery (We're talking about thousands of tiny pulses per second), because the voltage regulator will regulate the voltage at all times. Whatever energy that's been generated, needs to be released; and when the cap is charged to 13,8V, the voltage regulator will throw away just as much energy as when a battery is connected to it, as a bike can not consume more energy than what it can consume (lights, dash, CDI, those are the main electric energy consumers on a scoot, and they consume just about as much, with a battery, or with a cap).
It is true that a cap can charge quicker than a battery, and thus draw more power in the short time of it charging.
However, once the cap is charged, it acts much like a battery.
Also, there are scoots running perfectly fine with a Lithium battery. Those Li batteries can deliver upto 2 or even upto 500 cranking amps, way more than what most scoot wires can carry.
However the cap is most of the time not sucking power out of the regulator, but leveling off the voltage differentials and spikes. That's unlike charging from a zero charge, just dealing with 2-5V differentials, and a few amps.
Even if the cap can receive hundreds of amps, that does not mean that the stator can provide them.
It just means if the stator provides 10A, the cap will grab it, and if it provides 1A, the cap will grab that.

Likewise, it does not mean that the cap can provide hundreds of amps in a second, that it will deliver it. It depends on whatever device consumes that energy. If the bulbs only consume 2A, the cap will provide only 2A.


I'm still trying to envelop my mind around the idea of peak amp draw, as I believe those peaks to be so short, that they are of very little concern I believe.

Also, the stator delivers AC, which means the voltage regulator it does not provide a clean DC, but a rectified AC wave (basically hills instead of a flat line).
In that case, even if the cap can draw hundreds of amps, it can't do it, because the stator does not provide it immediately, but gradually builds up until it's peak voltage has been reached; and this goes on hundreds, or thousands of times per second; so the voltage fluxuations with a large cap will be extremely small, thus the power draws will be small too.

So even if the overall voltage would get higher with a cap, which would be strange, bu if it would be true,
then the leds/lights will just burn brighter, and the spark plug sparks harder, and those things will compensate the voltage differential.

Not meaning to disrespect you, or your ideas, but I'm trying to grasp what you're saying, but what you're saying in that voltage aspect makes little sense to me (I either don't get it, or it's just not there).

And even if it would be there, which may be, but I find it hard to believe, then the excessive voltage can easily be routed by putting a resistor in parallel to the resistor that is connected to the ground. But anyway...

I'll take your word on testing the cap. I don't want to run any unnecessary risk on my scoot, which will be the main reason I won't try it (yet), not because I believe the theory you explained me, but just because of caution. :-)

@ prodgit.... as you said...."Also, there are scoots running perfectly fine with a Lithium battery. Those Li batteries can deliver upto 2 or even upto 500 cranking amps, way more than what most scoot wires can carry." YES they could...CCA is what the battery can deliver...NOT what it puts out constantly. The amount of amperage passing through the wiring is based on the demand of the starter motor. That is why some of junk scoots I work on do ok when the cheap person uses a lawn tractor battery under their seat...and I KNOW many here have folks do that. I don't agree with it...but hey...their scoot not mine. So your Amp theory is wrong. NOW if we were talking a higher voltage..say 24V Marine battery...NO the wires could not handle it.
As for the cap....I am using the one from my sons 800W subwoofer..and it gives me an additional 15mph on the flats..
With all your ideas and suggestions....why don't you start your own business once you get a patent on your new found technology.
Your writeups amaze me..one minute you have all the questions...and the next you have all the answers. You act as if no scooter..motorcycle....or auto company has EVER tried the things you post...

;D..... Not a nerd fight...I am trying to learn from the expert....soo umm..hey....keep it down in class so we can read the lesson being taught by the entrepreneur...