New Casatronic (by Ducati) Static CDI Option

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Adam_Winstone
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It’s great, and much appreciated, when a dealership takes note of requests from its customers. Rimini Lambretta Centre are not the only dealer that fall into this camp, however, there are plenty of dealers that don’t; simply selling on whatever they happen to have on the shelf. In this case I approached RLC with a specific request for a bespoke part and they heard my case, listened to my reasoning, then said that they would see what they could do. Next thing I know, they’ve done it and made the bespoke part available to me… WOW!

Among those of you that may have invested in Sticky’s new ‘Lambretta Kits Book’, the keen-eyed may have noted that he states that all kits were tested using the fairly new Ducati Casatronic ignition, which he was very complimentary about. However, those that really paid attention may have noticed that he undertook all testing with a static ignition advance of 18 degrees BTDC (page 47), which caught my eye as the Casatronic ignition is not offered with static ignition as an option, rather, all off the shelf options come with a pre-set advance/retard ignition profile (Standard, Sport or Race). Whilst these profiles, determined by their respective CDIs, suit virtually all of the motor configurations on the road, I have a motor that is somewhat unusual and under certain conditions isn’t best suited to those advance/retard profiles.

So what is so different about my motor configuration…?

Well, nothing really, other than it is BIG cc and pulls a high top gear ratio at low RPM… and therein lies the issue; at low RPM the advance/retard function is in its early stages and the ignition timing is still relatively advanced. As we have all learnt in recent years, especially with the continued move towards hotter burning fuels, advanced ignition timing can easily lead to pinking, seizure or holed pistons. NB: The well conceived Casatronic profiles will avoid any such issues (subject to choosing the appropriate CDI for your engine spec’) and, to be honest, my request for a compatible static CDI is more about my own paranoia as it is about any issues; I have been running the Casatronic ‘Standard’ CDI for a while with no ill effects, although plug colour has looked a little light after periods of cruising; when the ignition timing is fairly advanced.

OK, to say that my motor is not unusual isn’t quite accurate. I run a self-configured Mugello 293cc motor (casing and crank from RLC, barrel machining and welding through Paul Baker at SRP), configured around a 72mm bore and 72mm stroke combination, running a 3.9:1 top gear ratio. As such my motor will be cruising at VERY low RPM, if riding with others at low speeds (e.g. Sunday rideout mode). Do note that this is relatively unusual as most tuned/kitted engines run more port durations and tend to run at higher RPM than standard, which is where advance/retard ignitions really come into their own. The advance/retard of the ‘Standard’ CDI is perfectly suited to the requirements of standard engines, however, motors (like mine) that are configured to cruise at less than standard revs will not benefit from an adv/ret function and may start to run hot whilst cruising. The new generation of expansions with more power at lower RPM (e.g. CST 3) will also restrict how far up the RPM range a motor rises, thereby limiting the ignition’s retard function.

If you look at the excellent graph provided by Ducati, which allows comparison of the Standard and Sport ignition profiles, you can very easily that the majority of retard function (both CDIs) happens between 4,500 & 8,000 RPM. If you have a tuned engine because you typically ride it at speed, all when and good, however, take a moment to look at the graph and consider what the ignition advance will be if running at 4,500, 5,000, 6,000 and 7,000 RPM… at higher top ratios and a range of speeds:


4.8:1 4.6:1 4.4:1

4,500rpm = 24° / 26.5°(Standard/Sport) 47mph 50mph 51mph

5,000rpm = 23° / 26°(Standard/Sport) 53mph 55mph 57mph

6,000rpm = 21° / 25°(Standard/Sport) 63mph 66mph 68mph

7,000rpm = 19° / 21°(Standard/Sport) 74mph 77mph 80mph


So, a Sunday rideout cruise of 50mph or a group touring speed set by a standard LI150 (c.a. 50-55mph) would see these configurations cruising at an ignition advance anywhere between 26.5 and 23 degrees, which on today’s hotter burning fuels see engine temperature starting to rise. Indeed, an EGT or CHT gauge will often show temperatures rising when trying to cruise at lower speeds. Whilst it may seem counterintuitive, the way to bring running temps down under these conditions is to drop a gear and run at higher RPM, which is uncomfortable for all members of said touring group and rider alike; engine revving hard and loud pipe saving even more lives (LOL).

… to cut back to the chase…


My engine, with its low revving and high top ratio is ‘the perfect storm’ for encouraging heat, whilst cruising at low RPM. What my motor could really benefit from is a lower firing point at lower RPM, which takes us back into the realms of a static ignition timing of around 18 or 17 degrees (give or take a degree or so for compression ratio variable)… a direct reflection of the static ignition timing used by Sticky for the testing of all kits in his new book. Indeed, Sticky was the first person that I approached over this and he took up my cause with RLC.

Fast forward 2 months and RLC have made available a static CDI for the Casatronic that fires at a static 17 degrees (strobe to double check if you source one); requested by me as it is suitable for a wide range of standard and tuned engines (remember that ALL kits were tested at 18 degrees for Sticky’s kits book), and a little accurate filing of the stator holes will allow a couple of degrees of adjustment in either direction (19-15), which covers the range that virtually all motors will run on today (standard to fast road tune).

RESULT - On the road my motor is now equally happy throughout the range and the plug colour indicates that it is running reassuringly cooler at lower RPM cruising speeds. As I said previously, the existing range of adv/ret profiles (CDIs) that are already in circulation are perfectly suited for the full range of road to race motors, however, this new addition of a static CDI simply widens the choice for those running oddball motors (like mine) or for those who have decades of experience running static ignitions and want to stick with what they know… I too am a creature of habit.

Thanks to RLC for being receptive to my request and for actually making this happen.

PS – 2 months on (CDI performing faultlessly) and RLC have just informed me that this static CDI option is now in production and they expect it to be ready in 2-3 weeks. I have no idea of the price and/or other ordering details so please liaise with RLC if you want to get your hands on one.

Adam
Adam_Winstone
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... sorry about the table, which reads correctly on a PC but not on a phone.
GeorgeS
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That's a good story, a dealer listening to customer needs and doing something about it.

I'm curious, did you ever have a look at a kheper cdi or other programmable options, or do these fall short of what you want?

Sent from my SM-G950F using Tapatalk

Adam_Winstone
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Joined: Tue Jan 31, 2012 8:54 pm
Main scooter: Lambretta GP
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Hi George

No, I've not tried the programmable ignitions. I have used a fair few different fixed profiles, not all linear, and still continue to use such ignitions on other motors, however, this motor had already shown itself to suit static (previously using a Varitronic with Readspeed CDI) but that had not been available for the Ducati Casatronic... until now.

Adam
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