250-500cc Ducati Ignition specs

I'm curious what your findings will be as well. I've been communicating with Willy from HPI and can commiserate, while he does always respond, occasionally it can take a few days and sometimes things seem to get lost in translation but HPI has been FAR more responsive and helpful than many other ignition suppliers. I'm in need of an ignition for my '92 WXC 360 and HPI says this: http://www.hpi.be/item.php?item=210R357 flywheel will work. The large diameter is spot on, however I'm unsure of the angle, a mechanic told me my taper angle is 6 degrees (not sure how to calculate) if that's the case the angle of the HPI flywheel will not work.
What got my attention regarding your post is the fact that you think the taper angle on your HPI flywheel while stated to be 4 degrees was actually closer to 6 degrees. I understand it is possible they sent you the incorrect flywheel and you're waiting on confirmation from HPI. I'll be interested in how things turn out. I also understand your frustration as I've been searching for a replacement ignition for my bike for nearly 3 months . Good luck

Yes, Willy has responded with the same answer for different questions. I believe the flywheel I got from them is 4 degrees, but I'm fairly confident the taper on my shaft is 5.5. I placed an order for a 5.5 flywheel and hope it fits. I figured out an easy way to figure out the taper. I'll post that a little later when I'm on my laptop.

A couple posts back, you can see the PDF with the tapers. One way is to use the wedge you cut out and try it in your original flywheel and see if it fits properly. The taper angle is figured out by drawing a line through the centerline of the shaft and then draw a line at the taper till it intersects with the center line and then you measure that angle. I'm not a mathematician or an engineer, so what I did was to plot my measurements, draw some lines and measure with a protractor. It's important that your measurements are pretty accurate. I drew a long line down a piece of paper and that will be my center line. I took my larger diameter measurement an plotted it near the top of the paper perpendicular to centerline with it being centered on that line. I then took my length of taper and made a mark. I then made a line using my small diameter at the length of taper measurement and centered it to the centerline. I then connected the ends of those lines making a V like you see on the taper PDF, but I made sure they intersected at the centerline. I then took my protractor and measured that angle. I hope this makes sense.

I'm picking up what you're putting down. I'm going to do some drawing and see what I come up with. Thanks. Keep us posted on how your current situation progresses.

I finally received the flywheel from HPI that has a 5.5 degree taper. It fits. So my WR300 has a 5.5 taper and I would suspect many other year 250's do also and HPI's info on their site is incorrect. I'll try to get it installed and running in the next couple of days.

This is what I got when I ordered the kit 210K159 that is supposed to fit 2001-2004 Cr250's and 2001-2013 WR250's.




It was missing the 110mm adapter plate. I'm not sure if it is supposed to come with the kit or not, but I had to order one separate. I also ordered a flywheel weight. They call it an inertia plate.



However, the flywheel was a different taper than my shaft. I checked several years of the CR's a WR's and according to the Husqvarna parts list, they all use the same crank as the WR300. After several emails to get the list I posted and doing some measuring, it looked like the 210R277 flywheel(rotor) would be the closest match, so I ordered one along with a puller. In the pic above.


Here is the adapter plate installed. I had to purchase countersunk screws to be able to install it.


Two of the bolts that hold the stator assembly to the adapter plate, hit parts of the engine case when threaded in. I chose to cut those two bolts flush with the back of the adapter plate.



The rotor fit with enough clearance from the stator plate. There is room for it to move closer to the ring, but the next size flywheel available ,210R036, would go on the shaft too far and would most likely hit the stator plate before seating.


Here's the inertia ring attached to the flywheel with the supplied screws. Unfortunately, the stator cover hits them.




So, I bought some countersunk screws and countersunk the holes. The bolts I bought are M6x1.0x10mm.





I had to cut the flywheel nut down to about 9mm so it will clear the cover. I just put it in a vise and used my angle grinder. I did my best to get it flat as possible.




I got everything installed, but some jackass used a 1/2" impact and stripped the darn flywheel nut. So I have to order a new nut. I installed the coil where the old CDI was attached and installed the HPI CDI where the Ducati rectifier was. I decided just to kick it over to see if there was spark. I've heard the spark looks weak on the HPI stuff and I had to close the garage door to where it was totally dark in order to see the spark. Hopefully, it will start up when I get the nut installed but will have to wait until it comes in next week.

thanks for the write up! great pics and info...its too bad there wasnt someone doing this already at hpi?!? hopefully they can use your info to have a better product. especially when so little changed on these bikes over the years...

I couldn't wait for a new nut. I bought a M12x1.25 lugnut just to try to start it. I kicked it slow a couple times to charge the cylinder and gave it heck on the third kick. It started for a split second and died. I kicked and kicked several times with no luck. I pulled the plug to see if it was wet and it was bone dry. I sprayed some magic juice in the plug hole, put the plug back in and it started on the first kick, but died. So my carb must be clogged from sitting for a year. I did take it apart before trying to start it and sprayed it with some cleaner, but I didn't check to see if the fuel passage for the metering rod was clogged. It was good to hear it run for a second. I'll mess with the carb in the next couple of days.

Check the float valve. Mine stuck closed from bad gas and sitting to long.

I can't believe I've been off my bike this long, it's just been sitting in the shed. I got an email out of the blue from Willy at HPI and they have a WR300 at their shop. They figured out what needs to be done and will be able to get what you need to replace the Ducati ignition. I need a different stator and rotor to make it work properly. They use a 110mm stator instead of using the 110mm adapter plate with the smaller stator plate. They also use the rotor(flywheel) for an RD250 and it all supposedly bolts up without any interference of the stator cover.

It Sounds like willy Talks about my bike...

Yup, that's the same picture he emailed me.

Hehe, he doesn t had this bike in his shop- He did sent me a whole lot of parts to try which combination will be the best.

I must have misunderstood him. He's sending me the 110mm stator and RD250 rotor and I've got some parts he said I can send back. It will be nice to have an option to replace the Ducati Ignition. I hope the HPI works as good or better. Not having a key way on the rotor does worry me a little, though.

I finally had the chance to install the new stator and flywheel HPI sent me. It was an easy install and the bike hasn't been started in almost a year and it started on the 3rd kick. I only rode it around the neighborhood and it seemed to work just fine. I have no idea when I will actually ride the bike offroad.

Get out there man !!