Better Coils for DS Motors

[koko64]

I have been reading the Fastbikesgear paper on ignition again and recommend it. It's packed full of info and worth every cent of the very affordable price for the information provided.

There is a section that covers the twin outlet coils (Beru brand) in the DS desmodue motors. Its apparently an economical design that splits the voltage between the plugs for each cylinder. That's not ideal for a higher compression motors with large piston diameters having the spark energy halved for each plug. Has anyone tried twin plug coil alternatives from Dyna or Nology? Did starting and engine response improve? I was exposed to aftermarket coils that didn't split the voltage back in my HD days (Accel ignition parts).

With the Multi desmodue DS motors I have run extra earth cables from the battery to the cases, from one side of the cases to the the other and from the battery to the starter motor body (or all of these in a chain to the starter from the battery earth cable). This often works to stop voltage drops to the starter and ECU as gaskets and threebond (and corrosion) can insulate and compromise a good solid grounding of the electrical system. Also tried an earth from the ECU body to the frame.

I'm starting to think that half the of problem may be caused by the stingy coils on these bikes. The Marelli starting sequence may not help. The three (small sample) single plug Evo engines I deal with all explode into life once they overcome the extra compression.

Would appreciate any suggestions or details of parts suppliers.

[ducpainter]

https://www.lowbrowcustoms.com/products/drag-specialties-5-ohm-dual-outlet-coil-single-fire-for-dual-plug-heads

Probably Harley oriented. Not sure of resistance required on a Duc.

Also the high price name brand spread... https://revivalcycles.com/products/dyna-coils-dual-output?variant=39629501399105&currency=USD&utm_medium=product_sync&utm_source=google&utm_content=sag_organic&utm_campaign=sag_organic&gclid=Cj0KCQiAxoiQBhCRARIsAPsvo-y2NsYYr1oMlCZ4SV3Jk8s0X-OqGCYLTtB6Y2ZLzDrAM8cqOZ2Rz8caAlngEALw_wcB

...and a 3 ohm version... https://www.denniskirk.com/dynatek/3-ohm-dual-output-coil-dc1-1.p20261.prd/20261.sku?gclid=Cj0KCQiAxoiQBhCRARIsAPsvo-wbNb7iorMfbqLDRyyK3frEg5mkP_gdD63clCqBJGh5hA1rFqU-OvUaAuPkEALw_wcB

[koko64]

Thanks DP. Surely Dynatek have something. I should contact Nology too. The DS coils are low resistance so I better start the emails.

Who halves the spark energy of a spark plug and doesn't expect starting issues on an over square, high compression motor.

Accel coils were the ducks guts back in my Harley days.

[ducpainter]

Thanks DP. Surely Dynatek have something. I should contact Nology too. The DS coils are low resistance so I better start the emails.

Who halves the spark energy of a spark plug and doesn't expect starting issues on an over square, high compression motor.

Accel coils were the ducks guts back in my Harley days.

I ran Accel coils on my kwak triple. That thing would run without rings.

[koko64]

In the meantime I'll make sure to gap down new plugs to 0.6mm max on the DS motors until better coils can be readily sourced.

I heard that Dynatech didn't have a good option but were working on it.

I''ll e-mail Liam at FBG about any new options.

[koko64]

https://ducatimonsterforum.org/index.php?topic=79167.0

Thanks to forum members for getting the info I needed which I have passed on to a shop in NZ which has done a lot of work around Ducati ignition. Liam at Fastbikesgear will let me know what performance coils are out there for DS motors and I'll post up for our members.

[greenmonster]

 

[MonsterHPD]

 

[koko64]

I sent through the info but have heard nothing as yet.