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Discussion Starter #1
My multi has always been a sketchy starter - although it's never left me stranded. I had to put in a new battery this year and figured I should at least get a season of easy starts but NO, it was the same old crank-crank-crank-crank-crank-crank-crank-crank-crank-START. The other morning I had to push the button twice and do two crank cycles to get it going. During the second cranking cycle, I grabbed the throttle and gave it the slightest of twists and VOILA! Instant start. So for the past few mornings I've been just touching the gas as soon as I push the button and it starts pretty much INSTANTLY every time.

Anybody else seen this behaviour?

I'm wondering if maybe I did a TPS reset it might help? Or just get used to goosing the throttle during cranking? I am sure I killed my last battery before its' time by cranking for 30s at a time, then riding 7 minutes to work in traffic and shutting it off..
 

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I'd start with a can of seafoam...might just be a dirty injector...adding throttle at startup is not really a solution...if that does nothing I would take a peak at the valves...check the timing... clearance...crud...

 

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Discussion Starter #4 (Edited)
I'd start with a can of seafoam...might just be a dirty injector...adding throttle at startup is not really a solution...if that does nothing I would take a peak at the valves...check the timing... clearance...crud...
Thanks, I'll try the seafoam and see what happens. I adjusted valves last winter so clearance shouldn't be an issue at 5K km but I'll check them again.

Not sure what I can do about valve timing - top end is stock AFAIK and belts are on the right teeth so... I don't have the angle gauge tool that bolts onto the end of the crankshaft to check the profile, I could probably make one pretty easily though. Ignition timing is electronic using crank position sensor and is not adjustable, yes?

If the valves are dirty like the ones in your picture what would cause that? I did do a compression check when I was overhauling the valves last year and it was fine (>140psi) so they are sealing. Bike runs like a top otherwise.

Because it starts the INSTANT I add a TINY amount of throttle I am just wondering if maybe it's just not getting enough fuel at fully closed throttle... yet once started it idles perfectly and has never stalled once running. Also it doesn't seem to matter if the bike is hot or cold, it never starts on the first crank like other bikes I've owned (when hot).
 

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The source of that carbon is still on the table...I've tried many solutions...none worked... currently working on an intake temp theory...the valves aren't getting hot enough to burn clean...if I run it hard it won't start hot...but let's not get caught up in this


....are you running an aftermarket exhaust?...exhaust flap still connected?

If you did the valves yourself what was your target values for the open/closers?

If you just put the belts back on them your timing is going to be ever so slightly off...I have a good post in Ducatimonster forum under monster821 full service on how to set the timing with a readymade tool...but to check them you only have to roll the engine on it's Mark and see how the cams lineup



 

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Discussion Starter #6
My bike is the last 2V airhead year ('09) so only one cam per cyl. Exhaust is stock non-Termi, cat is still there.

Valve clearance targets were 0.15 openers 0 closers (but still spin when rocker arm spring compressed). Actuals on the openers ranged from 0.12 to 0.14 measured after install on cold engine.
 

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My bike is the last 2V airhead year ('09) so only one cam per cyl. Exhaust is stock non-Termi, cat is still there.



Valve clearance targets were 0.15 openers 0 closers (but still spin when rocker arm spring compressed). Actuals on the openers ranged from 0.12 to 0.14 measured after install on cold engine.
My bad on 4v info to 2v problem....your timing is probably on or more than close enough with those specs....I'm running an m821that would only ever start on the second attempt but it always did start on the second try...until it didn't...it's a long story...seafoam helped initially and it is a simple solution and great at cleaning the fuel deposits...I was under 5% loss for all of my leakdown tests and I still had issues starting on the first go...the valves being dirty ultimately was what my problem was...the initial shot of fuel was just getting absorbed in the crud...but in the end when it got dire I was also experiencing no chance hot starts...it smelled off...like unburnt fuel off and the exhaust would load up with carbon if cleaned in short order...this again is something I've been dealing with since it was new...58k miles on it now...when it does act up now...it was typically after a hot lap in the mountains near the redline...running it around town with some "one and done" helps stave off the tear down...but in the end a walnut blasting brings everything back to zero...if your able to get a peak at your intake valve...if it's soiled then voila...that be the cause...

 

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Discussion Starter #8
That makes sense and would explain why some extra fuel would help. I will need to pull tank, airbox, throttle bodies... might be a fall project as long as it continues to start for me. I just picked up one of those tiny cameras on the end of a wire, maybe I can snake it in there somehow, if it was carbs there would be vacuum sync ports...
 

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I used the same camera...not for the pics I posted...but rather than go through all the removal I pulled the air filter and ran a hand down there with the camera...deposits will be fairly evident....if they exist...I seem to be the only person on here having to deal with it...I'll loose an exhaust valve every 23k miles if nothing is done..if you ever get an obnoxiously loud engine note on engine braking it's time to run some techron through the system and blast the valves...this has been my experience...for all I know it's a loose coil wire...lol



Lastly...it's a bit rare but try starting the bike with the exhaust can removed ...if it starts right up the cat might be fouled .. something new to try anyway
 

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Quit overthinking it. Just do what works. Have you never heard “ If it ain’t broke, don’t fix it” ?
 

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All the Ducati 4 valve engines I've had are slow to fire up, i was told that the engine management is set to fire up the engine after a few revolutions of wind over, by opening the throttle you could be giving the cylinders gas before the management system opens the injectors, but being ride by wire, i wonder if throttle position rules.
 

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If your woman likes a certain spot rubbed first, you rub it. Same with your Ducati. If it likes a little throttle, you give it to her. Give her what she needs to get going. KISS.
 

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The source of that carbon is still on the table...I've tried many solutions...none worked... currently working on an intake temp theory...the valves aren't getting hot enough to burn clean...if I run it hard it won't start hot...but let's not get caught up in this
The reason for the carbon is because of direct injection. With no fuel washing the back of the valves like pre-direct injection, there is no longer anything to keep the valves (and intake manifold runners) clean from the oil vapor from crankcase ventilation that gets pushed back into the air intake. The carbon remnants from the combusion process also adds to this unfortunate side effect of direct injection. This is why so many enthusiast car owners put catch-cans on, to catch that oil going back into the intake. Just look up "carbon cleaning" and you will see what I am talking about if you are not already aware.

For the most part, this is not that big of a deal as a maintenance item as most cars can be done at a shop for $300-$800 depending on the vehicle and motor, but if you have a car like mine (Audi RS7), due to the modern movement of "Hot-V" turbo setups, you can no longer remove enough of the top end due to reverse-flow heads to get to the valves without dropping the engine, so that $300-$800 turns into a $3000+ job.

I do not know what it would take to do a valve cleaning on a Duc motor if you have a lot of miles on your bike. Most cars it is recommended somewhere between 50k-75k miles depending on how you drive. If you drive it hard often, carbon build-up will not be nearly as bad as there is truth to the old "Italian tune-up" method.

Quit overthinking it. Just do what works. Have you never heard “ If it ain’t broke, don’t fix it” ?
I agree with that statement, but as an engineer, I counter it with "But why not make it better?"

On a related note though, I have been doing the same with my Multi. I can easily hear my throttle body move with the bike off, so I just barely open throttle, and I do mean barely, just a touch. If none of you have tried this, try it. Your motor will crank damn near 50% faster and I am not exaggerating since the intake stroke of these big-ass twins do not have to work so hard on the intake stroke to get some air in.

Another thing to consider is moving to a battery that has a lot more CCA. I measured my Yuasa on cold starts frequently and it would often drop to just a touch above 10v when first cranking and gradually increase until it finally fired. This may be because of all the electronics on our more modern bikes, but moving to a Gravity lithum replacement not only saved me a ton of weight high on the bike, but it actually holds full charge at 13.55 (mine does anyway). I have not measured the lowest point when cranking, but it starts on the third crank every single time now vs anywhere from 3-10 with the Yuasa I had in there. That Yuasa, in my unprofessional opinion, is just not enough CCA with all of the electronics that are on bikes these days.

I can hold my new battery with two fingers whereas the Yuasa I needed to hands to comfortably hold it for more than 15 seconds. In full disclosure, part of that reason is because of my small hands while the other and main reason is that Yuasa is just damn heavy!
 

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996R / 998´s need a bit of tickling to start..

  1. wind over a second or two
  2. crack the throttle, often it´ll try to kick
  3. stop winding over & leave it 30-60 secs
  4. try again with small throttle blips & normally she´ll catch
 

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On the 998 after it sits for a day or longer, the computer needs oh I forget, say 10 revolutions of the engine to find the crank sensor and that signal to the ecu. Then it starts immediately at idle. A likely forgotten point is that it has an immobilizer. If the key is on for more than 10 seconds before you hit the button, you can crank it all day but you won't have spark.
 

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On the 998 after it sits for a day or longer, the computer needs oh I forget, say 10 revolutions of the engine to find the crank sensor and that signal to the ecu. Then it starts immediately at idle. A likely forgotten point is that it has an immobilizer. If the key is on for more than 10 seconds before you hit the button, you can crank it all day but you won't have spark.
Did not know these tips at all - thanks!
 

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Qewklain, as an engineer, you should be familiar with the old saying:”When you’re up to your ass in alligators, remember your original intention was to drain the swamp. “
 

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Ducatis are not direct injected
Oh, right, I forget sometimes motorcycles, for whatever reason, have not yet made the move to GDI even though F1 cars are reaching over 15,000 RPM in a V6 with GDI...

Well, I have no ideas then. Ethanol? Yeah, I am going to go ahead and blame the ethanol and not riding hard enough from time to time to burn some of that crap off before it gets to cool down after shutting down long enough.

Qewklain, as an engineer, you should be familiar with the old saying:”When you’re up to your ass in alligators, remember your original intention was to drain the swamp. “
Cannot say I have heard that one before. I like the one my retired airline mechanic grandfather told me; "An engineers wet dream is a mechanics worst nightmare."
 
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