Total Loss Racing Ignition Options

[rlloydm]

Hi All,

Want to validate something that I heard before I spend any more money on the race bike...

A little background: I have been running a total loss Vape/Powerdynamo racing ignition on my AHRMA bike for several seasons now and it has performed flawlessly. I recently decided to change classes and rebuild the bike for considerably more horsepower (moving from mid-30s to mid-60s).

My porting guy asked if my ignition had static timing or operated on an ignition curve. I believe that I read that the Vape units are static so have been eying the PVL units. Problem is - I can't find any solid info as to whether either system has static or dynamic timing. Can someone more knowledgable weigh in here?

Thanks!

[m in sc]

They list this as the curve:

https://www.powerdynamo.biz/eng/kb/a100curve.htm

for this system

https://www.vape.eu/en/yamaha-rd350-tz350-sport-racing-ignition-rotor-nut

easiest way to know is to throw a timing light on it, make a timing pointer and watch it as it revs.. but i assume you motor is apart.

if not, then HPI system has a curve. However, you can always email vape and ask if your system does.. but they advertise it as such.

[teazer]

PVL, Motoplat, FEMSA and Hitachi TIA self generating ignitions don't really have a curve as such. They do have a slight retard due to the time it takes for those lazy electrons to find their way through the system but beyond that latency, they are static.

If you want a timing curve you need to look at a DC CDI system.  HPI sells one and so do Zeel and Ignitech but they need either an alternator or battery (or both) to provide the power.  There is no way to program those analogue systems abut they were designed with components that allowed for a certain (small) amount of timing curve.

Lucas (prince of Darkness) had an ET system which was essentially an alternator and as such timing changes were very limited to a short period before/after maximum flux. The same idea was used in Kokusan systems used on may factory race bikes from RG500 to Honda 6s.  Alternator generated a large enough pulse as magnets pass the cores to dump power into the CDI box. Very clever but not programmable.

So I think that if you need a self generating digital CDI, you may be limited to HPI. 

Total loss is a term usually used to describe a system with battery but no charging, the others used to be called magnetos but self generating is a probably a better term for them. We used battery plus Dyna but no on board charging on AHRMA race bikes and they are total loss.

A modern self generating system has to have a smooth enough constant 12-15v output to allow timing to be implemented but I could be wrong about the details of how they get a clean supply.

TZs used Hitachi CDI or Motoplat of Femsa self generating set at basically 19 degrees, but I suspect that you could get more drivability out of corners and a wider power band after peak with a digital system. 

You could also consider an RC battery running say 14v with a Zeel or Ignitech as long as your races are reasonably short.  They pack a huge amount of power into a small package.

[mixedbikes]

No idea if he still makes them, but on one of our race karts with a Pavesi engine, we removed the motoplat and I installed a Speed programmable ignition. It came with a selector box that you could put in 4 curves and change during the race if needed. Also had software to write your own curves. We found that is where a ton of power is, when you can put in the proper amount of retard at upper rpms. really nice unit.

[teazer]

you are correct that retarding the ignition after peak revs raises the exhaust temperature because fuel is still burning as it goes down the pipe.  That rise in temperature creates a faster speed of sound, so the end result is an exhaust that acts as if it was getting shorter and therefore continues to be the correct tuned length way past peak power revs.

And karts are the masters of living in that post peak region.

Road race motorcycles need more torque coming off corners more than they need over rev capacity, though that can be handy too.  And more advance at lower revs when the pipe isn't resonating is critical at lower than peak revs and where bikes spend a lot of time.

[rlloydm]

They list this as the curve:

https://www.powerdynamo.biz/eng/kb/a100curve.htm

for this system

https://www.vape.eu/en/yamaha-rd350-tz350-sport-racing-ignition-rotor-nut

easiest way to know is to throw a timing light on it, make a timing pointer and watch it as it revs.. but i assume you motor is apart.

if not, then HPI system has a curve. However, you can always email vape and ask if your system does.. but they advertise it as such.

This is exactly what I was looking for but failing to find. Looks like my system has about the same capabilities as the PVL (plus i don't need to weld on an additional bracket to hang a second coil).

Thanks very much, guys. Knew I could count on the wealth of knowledge here.

Mark, the motor is shockingly back together well in advance of the first race of next season, I just need to sort basically everything else out. I'll throw a timing light at it when I get her running and report back.

[teazer]

Just to be clear, those are both analogue systems as far as I can tell and are not programmable.  The "curve" is a function of component choices in the design and can't be modified or programmed.

That 'curve" is basically the same as an older Motoplat or HPI or PVL.  If you want to program more advance at lower revs or more retard at the top end, after peak power, those are not the ignitions you are looking.

[m in sc]

fyi, hpi offers a programmable version. ;)

[sav0r]

those are not the ignitions you are looking.

Somebody needs to make a Obi Wan meme that says that.

[rlloydm]

Just to be clear, those are both analogue systems as far as I can tell and are not programmable.  The "curve" is a function of component choices in the design and can't be modified or programmed.

That 'curve" is basically the same as an older Motoplat or HPI or PVL.  If you want to program more advance at lower revs or more retard at the top end, after peak power, those are not the ignitions you are looking.

Maybe once I'm a frontrunning racer! As it stands, I'm aware of several folks getting good, usable power from PVL setups and whatever timing curve is inherent to them. Given that the VAPE unit is similar (which I learned in this thread - thanks, guys!), I'm going to slap it on and run it/not worry about it for now.

I do hope to put my bike on Ed Toomey's dyno once it's done. I'll report back on power numbers with cylinders & heads given the full Scott Clough treatment, VM36s with big vForce reeds, VAPE racing ignition, and Swarbrick pipes if anyone is curious?