Electronic Ignition

[peter]

[Chappy]

[peter]

[lazairiii]

[Chappy]

Pete,

Thanks for the update! It is kind of curious though that the engines kickback worse with the Atoms, as one of their features is supposed to be less of it.

A big problem we would see with the Rotax 185's was ignition failure due to crappy capacitors, not so much the points. But when the capacitors (condensers in motorhead speak) start going bad, they cause the points to pit. If that doesn't actually kill the ignition, it does cause a change in timing and a poor spark. A completely failed capacitor will just about totally kill the spark. I can't tell you how many times I've been told that someone's engine has spark but just won't start. When we check it out, we find the spark is present but very weak. A pitiful weak spark is not enough to start one of these engines! They need a nice fat one to do the job.

The CDI units from Wildfire may be wonderful, and help keep the internals cleaner and the engine running in tune longer, but the price is too dear for many of us. At less than $25 each, the Atom modules seem like a nice compromise. I just want to get rid of the potential point and cap problems. I've had wonderful reliability with the Atoms over the years, and feel that they should potentially be very reliable on the old Rotaxes.

Chappy

[JPXman]

i still have my contacts at ducati energia in italy who were willing to do a bulk run for us. i put that project on the backburner due to not enough interest.

I need 100 engines worth of equipment for them to do a run. and i think the cost worked out to $100 per engine for the stator plate & coil, and the CDI coil... i still have my old list of those interested, but if you are ever thinking of upgrading, shoot me and email and when i get close to 100 i'll get the ball rolling.

Tyler

[Shannon]

Pete I'd be really interested to do testing with an Atom myself. This is probably how I'd go about it.

First I'd fine tune a set of new points (and condenser) to .016-.017 BTDC (~4.0-4.5mm) with a top dead center guage and multimeter. Note: I always change points and condensers as a pair.

Second tune a fresh carb (new kit) to the Wajax Rotax engine manual spec. Initially turn (L) out 3/4 to 1 turn, set (H) out 1-1/4 to 1-1/2 turn, adjust idle set screw so it's off of contact with the throttle stop lever and then turn it inward 1 turn so carb shutter is slightly open.

Running on Points I'd start the engine, warm it up and fine tune (L) as close to 1800-2000 rpms as possible without going much over 2000 rpms or below 1800 . Use the idle set screw to achieve what you can't get with the (L) adjustment. For example if I can only achieve 1780 with the (L) adjustment then the set screw is tweaked until the engine is idling somewhere around 1800-1850-1900-2000 range. With the engine running at full power adjust (H) to achieve max possible revs and then re-adjust (H) by slowly turning CCW to the point just before RPM loss is noted (usually less than 1/2 turn). Check: The engine should go from idle to full power almost immediately with no hestitation. Any bogging or loafing indicates a problem.

Now back to idle. The engine should be "Popping and Shaking" (Jumping and Vibrating) at idle (1800-2000) when set up according to the manual with points. Everything I've ever seen and experiened say that's how these engines are supposed to run at idle. I've never seen a smooth idling Rotax 185 to date. I fear that any smooth idling engine is one that is going to wear out early and be prone to failure. I can't confirm that however because I've never seen a smooth slow idling 185. That's not how these engine run with engine manual directed mixture settings. I have to remember that just because an adjustment of the carb will let the engine run a certain way that doesn't mean it's correct. The engine could care less about how fire gets to the sparkplug (points, CDI, Atom, Nova) but it does care about the mixture it's drinking.

OK these things done now swap over to the Atom and see how the engine runs. If there is a great difference between performance of the engine running on points and the engine running on the Atom then something must be amiss. If the engine runs about the same or better with the Atom I'd feel pretty confident about further testing.

[lazairiii]

[Chappy]

[peter]