I notice the same thing, Avocado. I can let my bike idle for a few minutes and the engine still feels like it's about to stall if I strain it at all, but even without a warmup it idles perfectly as soon as I've ridden it more than about 10 yards.Aguacate said:I wonder this myself. My driveway slopes downhill into the garage, so to not bother the rest of my fam with the fumes and such, I'll drive it up out of the driveway (on fast idle), stop on the side of the street, get pissed after about a minute because I can't get into neutral (although once it's warmed up I don't have any problem at all even while it is stopped), then just take off and drop the fast idle down back to normal.
It seems to be fine idling after I've ridden nothing more than about 10 yards or so. Then again, it hasn't been THAT cold up here in Seattle.
'splain this univerasl 'knowledge' please.b.h. said:you ride a ducati, universally known to have issues with flaking rockers. you should let it idle for a while to let the oil circulate (and coat the rockers/camshaft) before you take off, no matter how warm it is.
Running the engine with or without load doesn't change the pressure exerted on the rockers. Bringing the rpm's up will get the oil to the head faster than letting it idle slowly and it will warm up faster. Of course, you want to keep the rpms within reason and not load the bottom end to hard before the oil reaches the proper viscosity.b.h. said:you ride a ducati, universally known to have issues with flaking rockers. you should let it idle for a while to let the oil circulate (and coat the rockers/camshaft) before you take off, no matter how warm it is.
the ducati valve timing system uses overhead camshafts to actuate rocker arms which open and close the valves. "desmodronics"Ddan said:'splain this univerasl 'knowledge' please.
The user manual is specific about not doing that. The cable running from the fast-idle lever to the throttle body is tight. Turning the handle bars with the fast idle engaged will increase or decrease your throttle. If you have your idle up and you make a quick left, you could get an unwelcome shot of throttle. And on a cold day, cold tires might not agree with that too much.OwnyTony said:I just keep it at half choke(fast idle) for a mile (to the front gate of our neighborhood)
Turning the handlebars increases the throttle maybe 500 rpm at the most...and not all the time (at least that is my experience on my bike).chipazzo said:The user manual is specific about not doing that. The cable running from the fast-idle lever to the throttle body is tight. Turning the handle bars with the fast idle engaged will increase or decrease your throttle. If you have your idle up and you make a quick left, you could get an unwelcome shot of throttle. And on a cold day, cold tires might not agree with that too much.
My question was more on the universality of the problem. It is widely accepted that the rocker problem is an issue with the 4 valve motors, and is due to problems with the plating process. I haven't read or heard anything that connects the flaking to a lack of lubrication or warm-up.b.h. said:the ducati valve timing system uses overhead camshafts to actuate rocker arms which open and close the valves. "desmodronics"
the rockers have a special chrome-like plating which is intended to make them resistant to the wear and tear incurred from sliding across the face of the cam lobes. a nice film of oil between the rocker and cam surface is also especially helpful. other cylinder head designs have moving parts such as these bathed with a constant supply of oil. the ducati head/engine configuration allows the oil to drain from the vertical cylinder head when the bike is not running. if the bike sits long enough, it may take a few seconds (or minutes) for the oil to adequately flow back into the cyldiner head and coat all the moving parts. Hence, you could have metal on metal contact between the rockers and cam lobes. adding throttle makes the cams spin faster, creating more friction, heat, etc. on top of all that, ducati had a major issue with the quality of the rocker plating, supposedly due to outsourcing in the mid 90's. the plating on the rockers would simply "flake" off. leaving a bunch of gunk in the oil, and possibly also ruining the cam faces as well. the problem was seen mostly in 748/916/996 bikes, but I have heard of it in a some 2v bikes as well. as of 02' with the 998, a new rocker design seems to have fixed the issue....
but I still let all of my ducs warm up just a little while longer than other bikes ;D
this is just a broad summary. plenty of other info out there to be found if you're interested. but I hope this simple explanation helps.
The buckets, on a Japanese shim under bucket overhead cam engine, do not hold oil. They are facing the wrong way. The cams do not sit in a bath of oil either. The oil drains back to the sump, just like on a Ducati. In either case, some oil remains on the components depending on the type of oil and the time it sits. It might take 90 seconds for the oil to reach the head at idle, but will reach the head much faster if the revs are brought up a bit. I usually keep the revs just below 2k while putting on my gear. Then I start riding and keep the revs below 4-5K until the temp reaches normal.b.h. said:It's kind of common sense...... unless you can find someone to argue that revving a motor, while all the oil is sitting in the crankcase will have a positive effect on already questionable rocker plating
from Sigma Performance:
Now lets think about this, a typical Japanese DOHC engine will have nice little buckets over the valves; a pool of oil sits in a pocket above the bucket and the cam runs directly in the pool, oil is therefore present from the first second of running. With a Ducati Quattro Valvole, especially after it has sat around for a while, oil can take up to 90 seconds to arrive. The Ducati oil delivery system has no one way valve so as the bike sits unused the oil retreats slowly to the sump. When you start the engine the oil has to come all the way back up the long oil lines, it is not going to get there appreciably quicker if you rev it. The cams will not notice any difference if you are sitting 'off load' or are trying to ride it; but you do have some choices that will make life easier for the valve gear.