What I recently found out is that the motorcycle "typical timing curve" applies only to engines with a squish band head which increases the air/fuel swirl speed as RPM increases which accelerates the combustion. Heads without a squish band (like our stock ones) need an ignition curve that maxes out and then maintains that advance thru the rest of the RPM range. The latest Jaguar CDI allows you to select that curve for a stock head. This also applies to heads with too much squish clearance which has too little squish velocity. Also the higher the engine compression, the less advanced the timing needs to be. The stock CDI has timing that is suited to an engine with low compression and no squish velocity (due to lack of a squish band) although its spark voltage is too low for my tastes. More spark voltage means less misfires. This increases engine power. There's a study on this subject linked to on my CDI page.
Is there a downside to just retarding ignition? besides for loosing a bit of low end of course. Currently low on funds and that custom Cdi sounds expensive, though I’m sure it’s worth it. Just trying to keep detonation down for cheap. Thanks a bunch , your videos and website are the best source of knowledge for 2 strokes and these little bike engines. Hope you are do well.
I stopped making them and then let my friend in Australia make/sell them. His contact info is on the next page after the linked to page (in the video description).
old Texans talk slow. And many young Texans talk slow. And it's not because my mind is slow. Other than being raised around slow talking people, I've got a lot on my mind and talking slow helps me stay focused. Any way the only reason for these videos is to communicate information to you, not please your aesthetic tastes.
What I recently found out is that the motorcycle "typical timing curve" applies only to engines with a squish band head which increases the air/fuel swirl speed as RPM increases which accelerates the combustion. Heads without a squish band (like our stock ones) need an ignition curve that maxes out and then maintains that advance thru the rest of the RPM range. The latest Jaguar CDI allows you to select that curve for a stock head. This also applies to heads with too much squish clearance which has too little squish velocity. Also the higher the engine compression, the less advanced the timing needs to be. The stock CDI has timing that is suited to an engine with low compression and no squish velocity (due to lack of a squish band) although its spark voltage is too low for my tastes. More spark voltage means less misfires. This increases engine power. There's a study on this subject linked to on my CDI page.
Is there a downside to just retarding ignition? besides for loosing a bit of low end of course. Currently low on funds and that custom Cdi sounds expensive, though I’m sure it’s worth it. Just trying to keep detonation down for cheap. Thanks a bunch , your videos and website are the best source of knowledge for 2 strokes and these little bike engines. Hope you are do well.
yes you can retard the timing by modifying a woodruff key to offest the keyway about 5 degrees. It is explained on my site dragonfly75.com/motorbike
I tried to reach the Jaguar guy and he had said he wasn’t making them at the time. Any updates would be appreciated.
I stopped making them and then let my friend in Australia make them. His email is on the 2nd CDI page (see link in description)
Are these cdis available I was under the impression they're not being made anymore I'd love to get one
I stopped making them and then let my friend in Australia make/sell them. His contact info is on the next page after the linked to page (in the video description).
I stumbled upon someone using a 47mfd@200vac capacitor from the cdi to ground to retard the ignition curve on scooter cdi
Who send me a link please
Why did the motorized bike timing not retard as the Rpm’s got really high?
God you talk so slow. Nice video though learned a lot
old Texans talk slow. And many young Texans talk slow. And it's not because my mind is slow. Other than being raised around slow talking people, I've got a lot on my mind and talking slow helps me stay focused. Any way the only reason for these videos is to communicate information to you, not please your aesthetic tastes.