rev limiter
 

hi I would like to build a reve limiter on my zenoah G26RC1, its stock with the magneto flywheel and has the kill switch buton to turn it off

This is for drag racing purpuses what I want is to have a really high rpm engagment on my clutch an be able to reve up to a disered rev limit right before the cluch engages and then when I launch just turn of the rev limiter to lauch at a higher RPM.

This is what they call a Launch control in the Super FWD Honda Drag Racing World. have any of you seen anithing like this or have an idea on how to build a unit like this on, it shouldent be dificult as the cut its self will be controled by the same cables on the kill buton

thanks

RE: rev limiter
 

The Ryobi garden engines have a rev limiter nowadays.
Check out the flywheel US patent numbers if possible, and read all about it on www.uspto.gov

RE: rev limiter
 

How about just making locking prawl for the rear axle. Then you could hold full power and release it instantly.

RE: rev limiter
 

I really want the rev limiter effect I think it will be verry intidating when at the starline.

I went on the www.uspto.gov site but dint really find anything, and the locking paw is a good idea too but it will ware out the cluch fast and cause high temps on the clutch bell.
I have been hours on line and cant seem to find any DIY for this project but it shouldent be that hard. I wanted a circut bord type controler with a volume knob to control the rev. I I cant find a way to do it I will just rig up a micro switch to a spining motor and control the voltage to the motor, this will create the on off on off on off action needed for the rev limit hold

RE: rev limiter
 

I checked the coils on my Ryobi. Do a search on PHELON. A lot of stuff should turn up

US5931137 for example has spark advance controlled by the voltage of an aux. coil.

RE: rev limiter
 

I got interested and looked a bit further than my nose's length. Thus doing, I found US6408820 by Walbro, which has three electronic switches to control the CDI advance characteristics, including wiring schematics. The third switch seems to keep the idle low advance in operation until released.
Abstract:
A capacitor discharge engine ignition system includes an ignition coil having a primary winding and a secondary winding for coupling to an engine ignition spark plug. A first electronic switch has primary current conducting electrodes in circuit with an ignition charge storage capacitor and the primary winding of the ignition coil, and a control electrode responsive to-trigger signals for operatively connecting the ignition charge storage capacitor to discharge through the primary winding of the, ignition coil. A charge/trigger coil arrangement generates periodic signals in synchronism with operation of the engine. The charge coil generates a charge signal to charge the ignition charge storage capacitor, while the trigger coil generates a trigger signal for triggering discharge of the capacitor through the ignition coil. An electronic circuit for controlling timing of the trigger signals as a function of engine speed includes a second electronic switch in the form of an SCR having primary anode and cathode current conducting electrodes operatively connected to the control electrode of the first electronic switch, and a control gate electrode. An RC circuit, including a resistor and a capacitor, is operatively connected to the charge coil and the gate electrode of the SCR to prevent application of trigger signals to the control electrode of the first electronic switch during occurrence of the charge signal, and thereby control timing of application of the trigger signal to the control electrode of the first electronic switch. A third electronic switch has primary current conducting electrodes connected between the trigger coil and the control electrode of the first electronic switch, and a control electrode connected through a zener diode to the ignition charge storage capacitor. The third electronic switch prevents application of trigger signals to the control electrode of the first electronic switch at low engine speeds until the voltage stored on the ignition charge storage capacitor exceeds the zener breakdown voltage of the zener diode.

RE: rev limiter
 

ok I dint really understand much on the ignition sistem your talking about, I do know what a zender is I have used them to trick ECUs in cars, resistors capacitors coils all that I understand but after reading it a few times I got mixed up.

I am looking to make a rev limiter like the one in your car were if your in neutral and you rev up all the way the car its self will stop the RPMS at somewere around 7000rpms
going something like "ananananananananan"

Pe Reivers is there any way with what you read about that system to do just that, in the ign coil there are two contacts that when joined stop the ign spark to the engine. the engine has a kill switch that is just for that to shut it off. I get the effect I want by reving the engine full gas and just presing rapidly on the kill switch. I there any circut or elctronic that I could put between the cables were the kill switch is that would give be that on off on off on off effect I am looking for? If not I am going to install a micro switch on the cables and mount somthing like a small servo motor and gear box with a fingered wheel. I could even controll the speed of it from the 3rd channel like that if I disasembe the servo, and redo the gear box.

RE: rev limiter
 

Look into the Heli stuff. They run governors via the throttle. But I don't know if the response would be fast enough.

RE: rev limiter
 

I am not an electronics engineer, but a mechanical one. Yet my understanding is broad enough to be able to read electronic explanations.
The Walbro magnet CDI ignition provides leads on how to go about the issue, and keep the ignition at idle advance until you flip the switch. You need an electronics expert to desighn the system for you, and steer the ignition internal computer to achieve what you want. Some juggling will be needed to get the idle advance just right to limit your rpm to the desired value.
I also am inclined to think that there are better ways to do it, but this comes very close to answering your question.

RE: rev limiter
 

pape,
You can raise the rpm at which the clutch engages by lightening the clutch shoes or use stronger springs in the clutch. This will delay the clutch engagement, because great centifical force is required to throe the shoes out against the drum.

Dave