MoTeC Global Forum

Hi, I'm putting an m400 on a Yamaha wr450 single cylinder motorcycle engine. the stock ignition was CDI, so i have to switch coils unless i want to keep running a CDI, which i'm not sure if i am or not. i will be spinning the engine up to 10,000 rpm, so do you guys think that CDI is nesssary?

For either CDI or not, what ignition module (or CDI box, what are the differences between all them anyways) would you guys suggest for this engine? also, what coil would you guys use that matches the rest of the system as well?

I noticed that there is a coil/module combo from denso, this sounds like a very economical option that i am interested in, what are you opinions on this coil/module?

Also, if anyone has any experience on having the REF signal so close to the alternator in the flywheel cover, that would also be welcome. I plan on using a Hall sensor and embedding 4 magnets into the flywheel or using the stock variable reluctance sensor and adding teeth to the existing one tooth on the flywheel. Any opinions on this would be very welcome as this is my first motec setup. I have done data acq before, but not the fuel injection side of it. Thanks for your help.

Joshua

Are you sure this has CDi? Many of the Japanese bike say they have CDi when they are inductive. Measure the resistance accross the coil terminals to find out. I have never seen any improvement on 4cyl racers (up to 16,000rpm) with cdi but there is always a first time... Is there a separate cdi box? Use a std japanese Denso coil with a Bosch module. Make sure your ref and sync wires are shielded. I have run motec off teeth on the alternator case. Should be OK.

Thanks for your reply. I guess i never verified that it was a CDI. the manual just says it is and i took them at there word. there is only one box that controls everything on the motor.

so i've decided to go with a standard bosch module, and a bosch coil becasue i know they wil work together. i am having trouble getting specs on some of my existing coils to see if they will work. if anyone has a link to a page with some specs on them, i would really appreciate it. or if you could ive the specs on the denso coils that i have. it is pn 129700-4740-J0474. Thanks,

Josh

roepke44 wrote:Thanks for your reply. I guess i never verified that it was a CDI. the manual just says it is and i took them at there word. there is only one box that controls everything on the motor.

so i've decided to go with a standard bosch module, and a bosch coil becasue i know they wil work together. i am having trouble getting specs on some of my existing coils to see if they will work. if anyone has a link to a page with some specs on them, i would really appreciate it. or if you could ive the specs on the denso coils that i have. it is pn 129700-4740-J0474. Thanks,

Josh

Josh,

I am interested in logging the data out of a 450f - have you done that?

~Holmz

Not yet, but i will once our car is actually moving sometime in the next 6 weeks. I'm not going to be logging much except health check stuff.