Does my engine spin too easily?

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MotoMike
Posts: 487
Joined: Wed Aug 04, 2010 3:40 am

Re: Does my engine spin too easily?

Postby MotoMike » Wed Aug 24, 2011 10:28 pm

Since rotor timing is not mandatory, as it is in the non battery ignition bikes, I'm not inclined to rush into that job. Even with a battery ignition, I'm sure that some minimal advantage exists by peaking the alternator output coincident with the points opening. But since I have good spark now, and it runs like a champ I'll adopt a wait a little longer stance. Additionally, since it is bad for the RR to runt without the battery, leaving it so that it can't run without the battery is in a small way a RR preservation measure. If something else comes up requiring me to get under the rotor, I'll probably correct it at that time.

DewCatTea-Bob
Posts: 2897
Joined: Sun Nov 01, 2009 10:53 am
Location: Near SE side of Lake Michigan

Need for Particular Alt.rotor-timing with Battery-ignition ?

Postby DewCatTea-Bob » Thu Aug 25, 2011 3:34 am

" Since rotor timing is not mandatory, as it is in the non battery ignition bikes, I'm not inclined to rush into that job. "

____ Of course that's certainly understandable, and I surely hadn't meant to imply that maladjusted alt.rotor-timing is a fault which needs any required adjustment-attention asap (for battery-powered ignition).


" Even with a battery ignition, I'm sure that some minimal advantage exists by peaking the alternator output coincident with the points opening. "

____ Well I'm not sure I'd agree that the advantages are exactly minimal, but otherwise that thought is quite true, cuz whenever the alternator-output is max.peaking, system-voltage is then at it's highest/strongest point, which will thus saturate the ign.coil somewhat better than if the battery alone is only doing the job.
And in such event when the rotor-timing happens to be set completely-wrong, even though the battery will then receive charge-pulses just before and just after the point when the ign.coil could make some use of a DC-pulse, the battery doesn't hold-up that DC.peak-voltage in-between those pulses. _ And unlike capacitors, a battery doesn't store-up all the electrical-juice which charges it...
The ratio of the amount that's stored, to the amount that passes-through (to be wasted to ground), varies depending on the battery's condition/state,, and however also, when alternator supplied DC-pulses occur when the ignition-circuit is not drawing current-juice, a greater amount of the juice is thus-then wasted (through to ground), compared to when the ignition-circuit is sharing the DC-pulse with the battery. _ So when the DC-pulse as well as the battery's stored-juice are both available together to power-up the ign.coil, then system-voltage can't easily drop (while the ign.coil is powering-up), as would be the case with the battery powering the ign.circuit alone. _ So depending on the battery's state of condition, when the alt.rotor is timed correctly, it's then possible to get a better ign.spark with use of the extra power-juice that would otherwise just be wasted, straight-through the battery to ground.
Thus having an alternator's DC-pulse timed to coincide with the ign.circuit's demand, leads to greater electrical-juice system-efficiency !


" But since I have good spark now, and it runs like a champ I'll adopt a wait a little longer stance. "

____ I believe that's fairly sensible, as ya don't want to be torn-down during riding-season.
I-myself have never bothered to tear-into a (battery-powered) motor just to correct the alt.rotor timing ! _ As I'd always wait until the clutch (or something in there) also needed attention.
__ You just have to keep hopes that your battery never gets run-down somewhere where help can't find you, since you likely won't get going again with just one push-start attempt. _ But if the battery is only run-down due to having left the lights on (while you're inside some-place), then several pushes in 1st-gear may get the battery back-up enough to get a starting-spark. _ (And in such a case, hope you're in good physical-shape.)


" since it is bad for the RR to runt without the battery, leaving it so that it can't run without the battery is in a small way a RR preservation measure. "

____ Indeed so, but perhaps at the expense of a long walk with an ENTIRE valuable-Duke left behind. _ (I-myself would rather chance just having to replace the R.R-unit !)
__ Ya can tell when your (stock) system is running without the battery, as then the lights will flicker brightly.


" If something else comes up requiring me to get under the rotor, I'll probably correct it at that time. "

____ If your Wide-Case (set of three) original alt.stator wire-leads have never been replaced, then look-forward to doing that as well, as their insulation-covering does go bad !


Hopeful-Cheers,
-Bob
PLEASE NOTE... If this-post is not-yet signed-off with '-Bob', then I'm still in the process of completing it,, and if not also included with 'DCT' near bottom as well, then I may edit this post's wording at a later time. - Dct.Bob


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