Is it within normal operating range that the horizontal air bypass screw is fully closed, but the vertical is open a full turn?
I was curious if this might be a larger than normal difference and indicate an issue with valves. I expected both screws to be a little more similar when I checked their settings.
Bike idles at 1400-1500rpm and I wanted to lower it a bit.
I am also wondering if this could fix the idle, it hunts up and down when the bike is hot on restarts.
I have VDSTS and have done TPS reset, it is at 3.2 degrees. Is this normal for the S2R1000?
Thanks
FWIW mine are almost 100% closed on each cylinder...its just where they ended up to get it to idle @ 1300 (lowest I can get) w/ CO @ 7%
this thread helped me a bunch
http://www.ducatimonsterforum.org/index.php?topic=37125.0 (http://www.ducatimonsterforum.org/index.php?topic=37125.0)
..are you using a CO monitor and vacuum gauges when tuning the bike?
Yours will probably be different based on your mods...I have full arrows, flashed ecu to DP specs, crankcase breather direct connected to the airbox, removed emissions can, and K&N
I did read through that thread and found a good deal of info on the multi forums specific to the 1000ds. I'm still looking and thinking...
From what the manual says, only the throttle body with lowest vacuum is adjusted to match the other. So one should be closed and the other open to some degree. This makes the balancing screw and the one adjusted air bypass screw the only mechanical adjustment points for CO and vacuum.
I have not tuned before, but I am the second owner and have no history on the bike.
I'm just trying to think of where to start hunting down the source of the high idle. Im wondering if the previous owner maybe tweaked the idle stop screw, but I haven't exactly located that yet.
first I reset the TPS
then i set vacuum w/ the balance screw, just adjusted it until they were the same...not sure how you can match one to the other independently....as you adjust the screw one will rise as the other falls....its not like balancing carbs w/ separate adjustments
once you get the vacuum equalized, set your idle speed w/ the by pass screws to where you want it.... then adjust the CO w/ the fuel trim on the vdst...
they will all change a little as you make changes, once you are in range just tweak things ever so slightly to get a good balance
Mines an '07...it doesn't have an idle stop screw ...i think your high idle is because the one screw is fully open...
Mine is an 07 as well. I was looking for a throttle stop screw and found nothing.
I'm assuming when you adjust the balance screw you have the air bleeds totally closed.
I've read quite a few different methods for tuning and setting idle.
It's weird the manual states nothing about the balance screw and only has some tidbits regarding adjusting only one bypass screw.
I do like the straightforward method you described above. I appreciate the info!
Since you don't know why the air bleeds are that far off. the only accurate method I can think of is to first check all base settings, including cam timing. You don't need to go as far as degreeing the engine, but your '07 does have adjustable pulleys. If the marks are off, loosen the pulleys and line them up. The screw on the throttle is a stop screw. Some folk try and adjust idle speed with it. This throws TPS out of whack. AFIAK, there is no factory method for adjusting the stop screw. Factory techs may know different. Anyway, the throttle should be open enough to not hit the bore, but not open enough to affect idle speed. If that is good, set TPS. Do check for exhaust leaks.
The ideal method for balancing the air bypass screws is with an exhaust analyzer with a probe that fits into the bungs in the exhaust header. Short of that is adjust for lowest hydrocarbons once desired CO is reached. You may need to go back between throttle synch and CO balance a few times.
Or you could try setting each air bleed at 1/4 turn and see how it runs.
Tried 1/4 out on each bypass screw and the bike did not implode. It actually ran very smooth. The idle is still right around 1500, though.
Is there any reason to believe a TPS reset is needed after putting the bypass screws in a different position?
And I found the throttle stop screw. You have to move the throttle cam to see it. Mine is still painted making me think it has not been messed with.
The only way I know of checking if the TPS is correct is to hook up a factory scan tool or a computer loaded with Technoresearch (or other) diagnostic software. The TPS is set electronically. If you don't know anyone with the equipment a dealer shouldn't charge a lot. The Technoresearch software can be purchased from http://www.ca-cycleworks.com (http://www.ca-cycleworks.com) (a board sponsor). On the other hand, if the bike runs well, chances is it is OK. I would check it anyway.
I assume you checked for vacuum leaks? Is the stepper motor functioning properly? Did you check idle speed with a real tach or are you going by the one on the bike? You might want to check that all the sensors are working correctly.
I do have VDSTS and reset the TPS recently.
Is the stepper motor working? well, it hates life. I'm not sure why, but I have been suspecting the sensors that give the idle stepper its input (air temp i think was the main input) may be wonky. the idle hunts up and down when i start up when the bike is hot. I can throttle coach it into submission and it will idle fine at 1500 until the next hot restart. Cold starts its fine, goes right to 1500.
I have checked for vac leaks but will check again.
I am going by the tach on the bike. Hadn't considered that may be off, but my bike does sound like it idles a bit high compared to my old 695 and 696.
I hate the stepper but can't understand why it seems to work on other new bikes and all the 4Vers. I wondered today if my air filter may be trashed and contributing to the issues.
I should mention bike has full Termi, DP ECU, open airbox.
I am planning to check the trim level as well.
Checked the plugs and they are quite dark but not blackened. I can take pics and video if it might help, but I don't think it's lean.
No backfiring problems.
I didn't see anything off on the cam marks when I changed the belts a few weeks ago. I wasn't looking specifically, though. I can check if this ,..... Tomorrow, I'm into the Mich Ultra's for a bit this evening.
my tach is a little off reads over 1400 when the vdst says 1300...it tend to believe the vdst
I don't know much about the stepper motor since I haven't had to mess with mine (yet)...found a little info here
http://www.ducatimonsterforum.org/index.php?topic=39882.0 (http://www.ducatimonsterforum.org/index.php?topic=39882.0)
however if its hunting it sounds like the culprit, since the stepper seems to act like an automatic air bleed adjustment. sounds like you can try and clean it per the above thread
Since the bike idles smooth I wouldn't worry about the cam timing right now. I would check the temperature sensors with the VDSTS and get the bike on an exhaust analyzer, even if it costs a few dollars. As gr1976 said, stucksticking stepper motor is a possibility. Can you feel it vibrate? If you do something to affect idle like add propane into the air intake or open the air bleeds does it try to compensate?
It idles smooth when it idles without hunting.
I wonder if the vacuum leak theory may be onto something. I'm going to really look over the hoses that run to the stepper and see if maybe there is a compromise in vacuum somewhere.
I just don't understand why it only hunts right after a hot startup, but cold starts are OK and once I throttle coach it to calm down the hunting, it settles and is fine...maybe the battery is going out?
I don't hear the stepper or feel vibrations, but I'll check on that today. When I adjust the air bleeds with the bike running, it does stumble a bit as the stepper compensates. I think it's working, it's just either sticky or getting bad input.
I have to admit I'm a bit lost as to why the air bleeds did not lower the idle...
I'll use the VDSTS to check the idle and report back if it's simply the tach on the bike being off. That would be a nice thing to find out and make the idle hunt the only gremlin to hunt down.
Thanks so much for the input so far!
Idle speed is controlled by the stepper motor as long as all else is in parameters. Bad sensor input, CO too far or too much of a difference between cylinders of can cause hell with the stepper motor.
I have to get new tires put on this week so I'll ask how much they want to tune. My guess is they will want alot.
I somewhat understand the concept of the stepper motor system. I just think it's goofy and prone to break down.
I'll be working on the issues today.
A few minutes this afternoon with the VDSTS yields the following:
-The bike is idling fine, right around 1250 according the digital output on the VDSTS, like a champ. Dial says 1500, I don't care anymore and that's a beautiful thing. Case solved, I think...
-I put my bypass screws back into the original positions from when I bought the bike; horizontal closed, vertical 180degree open (earlier I had said it was a full turn open, I screwed up, it's only 1/2 open).
-The trimmer was set to 22. I changed it to 20 to mess around a bit and see if I can feel a difference, can't really.
-I did a series of TPS resets after whuwacking the throttle closed a few times in between the resets (I was hoping to seat the valves real well). It seemed to alleviate the idle hunting a bit. I noticed when the idle was stable, the TPS was actually varying between 2.9-3.3. Is this normal?
-Earlier I called the dealer, they want 1.5hrs labor to balance throttle bodies and set CO. That's not happening. I know I need a gastester, but just being honest, I don't have the cash for it right now so it has to wait. I called around town looking for someone with one, but apparently only the duc dealer seems to have one...so far....I'm determined to find someone to let me use theirs for cold, hard Bud Lights. I think I will.
So for now, the high idle I think is not actually a high idle, but is just fine. I am still trying to figure out the idle hunting, but I'll ride tomorrow and see if my barrage of TPS resets I did today maybe helped. I'm not going to bother with the full tune until after I do the valves in about 1000miles. So far it has been fun messing with it a little.
Well its still hunting idle when hot. I really hate the whole stepper system.
Can someone comment if it's normal for the TPS setting to fluctuate slightly while the bike idles?
Also, my vacuum hoses of the stepper system are not hose clamped. I was thinking of maybe trying to snug the hose connections to see if there is a difference.
Thanks for any help.
I think some variation is normal, as long as it stays in range there should be no problem.
Snugging 'em up can't hurt. Was it hunting when the screws were even?
Yea, it was hunting with both out 1/4 turn. It seems I can settle the idle more easily with some throttle coaching when one screw is closed and the other is open half a turn.
I don't see any obvious air leaks, but its still hunting. Today on my ride home it started hunting at a stoplight, but after I got home I tried a restart with bike still hot and it didn't hunt, idled fine. I really don't understand why it's intermittent.
The bike is still hunting intermittently, usually when the engine temp is above 160F.
I've got to get my ducs in a row getting ready for some upcoming maintenance so for now, things are going to stay as they are on my bike.
I appreciate all the input given on this thread! Thanks guys.
Try to find someone with an exhaust analyzer after you do the service if the problem persists. Since you are running a DP ECU I am surprised you are having this problem.
Oh, do look at valve guide clearance while you do the service. This could (hope not) be your problem.
Valve guides have been a suspicion of mine considering the limited history I know about the bike and the numerous similar stories online.
In order to replace valve guides, it's necessary to pull the heads, isn't it?
The hunting is not as bad with my trimmer set a tad lower, but I still have to quell it with throttle coaching.
I'm at 6900 miles now, so I'll be diving in for the first time probably around January to do the service.
I've got most of the tools I need, and am planning to rent a kit from ducatitoolrental.com for the rest of the stuff including the shim kit.
I just gota figure out where to find a gastester, although I see that ducatitoolrental.com actually has a gastester that can be rented.
Heads need to be pulled, guides need to be reamed after install and seats ground. Ducati did have a known guide problem on some liter engines. You might get some "good will". Contact them. If your dealer is good, do it through them.
The reason I didn't mention guides before is I don't think the guides are as much an issue if you are running open loop. Since you are adjusting your valves this is just the perfect opportunity to check .I still think adjustment will solve your problem. Wiggle your exhaust valves in the direction of the rocker arm. Measure with a dial indicator. Half of that is your clearance.
Ducati tool rental? Definitely post your experience with them.
I'm hoping it's not the valve guides...
I contacted the dealer about the valve guides and he is checking to see if there is a VIN connected recall or bulletin of any kind. I'm pretty sure they would not be willing to check, but if I know the guides are bad I may pursue some "good will" service from DNA (I really hope it doesn't have to go there). Bike doesn't leak oil or smoke noticeably.
I will most definitely report back about how the tool rental goes.
Thanks for all the info, howie.