ESE's works engine tuner

[TZ350]

From page 181

Thomas and Bucket have got the generator system working OK now, using two coils with 420 turns of 0.6mm enameled wire on each and wired in parallel. The system was made with a new $15 pit bike rectifier/12v-regulator from Trademe and two rolls of 0.6 wire from JayCar at $11 each.

10.74 AC Volts from the generator, 13.9 DC Volts from the Pit Bike Rectifier/Regulator.

To find DC Volts from an AC source and full wave rectifier and smothing capacitor, multiply AC volts by 1.44, less 0.5 to 1.0 Volt for the forward resistance through the regulator........

How are you guys powering the ignition units?
12v battery?

Hi Koba, as you know, we made our own generator by rewinding the ignition coils so they put out about 14 Volts at 2.5A and used a cheap Pit Bike rectifier regulator to charge a 12 Volt battery.



We used one of these jell type batteries they work well on the CB125T's up here at Mt Welly, but the vibration of our 2-stroke killed it.



So in a moment of brilliance I grabbed the 14 Volt battery from a Black and Decker battery drill.

Worked great, lasted all day on the dyno, then after a while the battery lost power and the ignition started playing up.

When the 14Volt batteries voltage dropped the ripple voltage from the generator was false triggering the ignition and we were getting multiple sparks per revolution...... and we could easily see this with a timing light.

It only took Thomas and Bucket a few moments to relise my mistake.

A 12 Volt charging system dosn't work well with 14 Volt batteries......

Our next move is to try a capacitor instead of a battery, a 24V 100,000 uf electrolytic should do it, our IgniTech ignitions will run any where from 10-18Volts and draw about 0.2A at idle and 0.8A flatout, so the 12 Volt charging system and capacitor could be OK.......

[koba]

ahh, true! I lost that in all the information!

Thats damn smart.

[Henk]

I have heard of people running big caps instead of batteries and charging systems in the past and going total loss that way, not sure how it would work for a long race though. If you go for a huge cap instead of a battery and still run the charging system it may pay to slap a smaller cap in parrallel, electrolytics tend to be a bit slow so you may need something else to knock the spikes off.

[bucketracer]

it may pay to slap a smaller cap in parrallel, electrolytics tend to be a bit slow so you may need something else to knock the spikes off.

That was the problem with the nearly flat battery, its internal resistance made it a bit slow too and the charging system could develop voltage spikes (ripple voltage) across it.

[Yow Ling]

I have heard of people running big caps instead of batteries and charging systems in the past and going total loss that way, not sure how it would work for a long race though. .

Its not total loss if you still have the charging system. Caps are great but wont initially power up the electronics. I have a zeeltronic that likes a battery , it is only the signal processor and will start without a battery but goes into panic mode with no battery at 6k , a revlimiter at that speed is not very impressive. Battery wire fell off in the dipper at ruapuna, I thought it was seizing.

[F5 Dave]

Yeah I've had to put on a bigger battery with my Zeel, they are pretty thirsty & need a decent buffer. For a racebike I just want to push & go. Batteries are just a pain & another reason not to finish a race. Seen it again & again with people running total loss. How to ruin your day in several drawn out episodes with lots of swearing, adult situations & self flagellation.

[Bert]

Yes the square GP port is a problem, 70% did not allow much rounding of the window, 75% was as much about improving the shape as increasing port time area.

Sorry for dredging this up,
though i fully understand your problems with square ports (thanks Suzuki), I was actually referencing the work done on the port itself (red circles, as seen in earlier photos). maybe a bit more rounding in these areas might provide less pressure/whatever on the piston/ring: you have plenty of bore to work with.

now here is a ring gobbler (something like 77-78% of bore):
http://www.kiwibiker.co.nz/forums/al...hmentid=203280

[TZ350]

Thanks Bert, you have a lot of interesting pictures on your site, http://www.kiwibiker.co.nz/forums/al...p?albumid=2701

I did not know you had posted about your build, very interesting, I will have a good look through it.

If anyone else has posted their work I would love a link so I can read through it..........

[TZ350]

Yeah I've had to put on a bigger battery with my Zeel, they are pretty thirsty & need a decent buffer. For a racebike I just want to push & go. Batteries are just a pain & another reason not to finish a race. Seen it again & again with people running total loss. How to ruin your day in several drawn out episodes with lots of swearing, adult situations & self flagellation.

I totaly agree, even with the very low current draw of the IgniTech CDI Ignition total loss can be a problem. We will be looking at improving the charging system.

Easyish to make a 12 Volt one using some 12V Rectifier/Regulator unit but a bit tricker to make a 14 Volt one from scratch.

[Henk]

Charging voltage for a 12V system is up around 14 vols in any case. Might not be as hard as you think.

[F5 Dave]

some regulators are set higher than others. Used to run ~ 13.7 but newer ones on some brands try to get away with higher voltages probably to account for voltage loss through nasty contacts etc so have been creeping up to 14.5.

Of course if you don't have the output power it will sag under load to less than regulated voltage. Add to this cheap small batteries vibrating their plates apart & creeping internal resistance. Those non adjustable MX CDIs are looking good again despite their compromised curve.

[Bert]

Modifying an analogue CDI (if you can get them apart). some might find this interesting:
http://www.geocities.com/a57ngel/moto/CDI.html
http://www.geocities.com/a57ngel/moto/CDI-mod.html

[TZ350]

Modifying an analogue CDI (if you can get them apart). some might find this interesting:
http://www.geocities.com/a57ngel/moto/CDI.html
http://www.geocities.com/a57ngel/moto/CDI-mod.html

Thats interesting Burt, if one had the stator part of a MX ignition they could follow the schematic and make the CDI part.

Another usefull kit from JayCar. Kit number KC5466 $29 aprox. Its a CDI kit to replace a bikes blown CDI. This could be adapted in all sorts of ways.It uses the bikes own high voltage stator coil to charge it and the trigger coil to fire it.

It would be worth looking at the Jacar CDI kit's to see if they can be modified to give an ignition curve too .........

Hmmmmm thats got me thinking about them again.

[Bert]

It would be worth looking at the Jacar CDI kit's to see if they can be modified to give an ignition curve too .........

I maybe wrong but I think Skunk has build one of these for his RD/ZXR project
http://www.kiwibiker.co.nz/forums/blog.php/2010-Skunk

the kit has potential as it has a fixed pulse (no advance/retard) but requires a trigger (from a Hall effect sensor etc). now surely it is not that difficult to have it set at the most retarded setting & have some smarts sitting between the trigger and the trigger input of the CDI (that could be changed at different RPM = pulse frequency) which acts as a advance/retard emulator by controlling the timing of the trigger...
go back 50 odd pages and I think we have had this conversation before...

[TZ350]

Modifying an analogue CDI (if you can get them apart). some might find this interesting:
http://www.geocities.com/a57ngel/moto/CDI.html
http://www.geocities.com/a57ngel/moto/CDI-mod.html

Hi Bert

The Jaycar kit looks like it could be modified to have a retard curve as shown in the link on your post.



It also looks like it could be made to run without a seperate trigger coil.

Although a trigger coil could be fitted, and it could even be as simple as a few turns (60?) of wire around the main HV generator coil.