Quote from: VeryMetal on July 21, 2008, 06:33:55 PM
Also, just out of interest - what rev range do you guys run your ducs within? Mines an 02 750 monster ie dark, I tend to keep it within 4000 to 5500. Am I going to torture the bike going any higher? I assume not but I just want to see what others think.

- My manual says "never exceed 7,000 rpm". 

If you were driving a Nascar with that powerful engine would it do the same thing since it's made to run smooth at such high RPMs vs. a traditional vehicle which runs smooth at lower RPMs?  I'm thinking so but I've never cruised my neighborhood in something like a Nascar either.

Quote from: DrNo08 on July 21, 2008, 06:45:57 PM
- My manual says "never exceed 7,000 rpm". 

I typically run mine around 4,5 -5 but thats just steady cruising. When accelerating, i get it up to 7, 8, and higher. Pegged the limiter several times. Not a big deal.

Quote from: DrNo08 on July 21, 2008, 06:45:57 PM
- My manual says "never exceed 7,000 rpm". 

i think that's for the 621-1500 mile range.

I fought the 4000 rpm hiccup/stumble thing for 2 years.  Multiple tunes, plug replacements, filter changes, BG44K, different gas, 14-tooth sprocket, blocking the airbox intake to richen the mix (diagnostic).  It has been fixed completely with the addition of a Techlusion TFI fuel computer.  The settings I use on the TFI coincidentally perfectly match those that Brad Black at Moto One arrived at on the M800 using a dyno.  I assume from this that many Monster 800s run lean, and that the ECU trim adjustment does not adequately address the problem at all rpms.

I have no financial interest in Dobeck Performance, but this little box has completely changed my riding experience.  The bike just runs real strong all the time now.  Every ride I used to dread that stumble, now it is gone.

Quote from: VeryMetal on July 21, 2008, 06:33:55 PM
I was just thinking, not very hard but thinking none the less. I can see how it could be caused by a tight spot in the chain or even chain slippage (which would probably only occur if your chain was so loose it was practically dragging on the ground) but wouldn't it be consistent? It wouldn't go away, no matter the speed, maybe it would get so fast around 60 or 70 mph that you wouldn't notice it. I don't know, my logic is probably flawed, can someone clear that up for me?

It's a very good point, but in my FHE with my F650, the "surging" of a buggered chain is more apparent at partial throttle than WFO.

Quote from: Mr Earl on July 25, 2008, 09:44:07 PM
  It has been fixed completely with the addition of a Techlusion TFI fuel computer.  The settings I use on the TFI coincidentally perfectly match those that Brad Black at Moto One arrived at on the M800 using a dyno.  I assume from this that many Monster 800s run lean, and that the ECU trim adjustment does not adequately address the problem at all rpms.

Besides the aforementioned theories, I think it does have a lot to do with the FI being programed very lean for emissions reasons.  If I knew everything else was in perfect order, that's where I'd go.

Quote from: VeryMetal on July 21, 2008, 06:33:55 PM
Also, just out of interest - what rev range do you guys run your ducs within? Mines an 02 750 monster ie dark, I tend to keep it within 4000 to 5500. Am I going to torture the bike going any higher? I assume not but I just want to see what others think.

I've got a '97 M750 (carb'd) and I keep it within 4,000 and "wildly oscillating tach needle" because my tach is wonky past 5,000 

I have the same issue below 4,000 RPM, too. Thought it was just me!

Put on a 14 tooth countersprocket, or downshift.

Quote from: dlearl476 on July 26, 2008, 07:36:05 PM
It's a very good point, but in my FHE with my F650, the "surging" of a buggered chain is more apparent at partial throttle than WFO.

Besides the aforementioned theories, I think it does have a lot to do with the FI being programed very lean for emissions reasons.  If I knew everything else was in perfect order, that's where I'd go.

Thanks for the reply! So am I to assume that getting my bike dyno'd might help with this? To be honest I don't experience it as a problem really seeing as I'm usually over the rev range where it occurs, but I'm curious as to whether my bike would benefit greatly from being dyno'd or is it the case that the ecu (correct me if I'm wrong in thinking this is responsible for controlling the fuel injection) would need to be remapped? This TFI thing sounds interesting.

Although I've never dyno'ed my bike, the quoted cost locally exceeds the price of a new TFI.  And with the stock ECU on your M750, the dyno run wouldn't solve anything as the 5.9 ECU isn't re-mappable.  You can have the "trim" adjusted, which sort-of controls mixture, but the several attempts at this by my dealer were unsatisfactory.  OTOH, the TFI has been TOTALLY satisfactory, and no need for dyno tuning.  Though you could if you wanted to eek out all power possible.  Tuning with the TFI is kinda like adjusting a carbed bike, but easier.

I'm sorry, but I don't buy this theory that the Monster is such a hot rod that it can't be expected to run smoothly.  Or that we should just accept this stumble/hiccup thing.  Drove me crazy for too long.

It seems to be the general consensus among everyone I know who knows a significant amount about Ducati that the 5.9 ECU software is the best so far. My bike burbles a little around 4k but at this point I think I can live with it if it's not detrimental, I don't like riding it that low anyway. It doesn't bother me at all now that I know it's not something to worry about.

The Techlusion TFI seems nice, they don't seem to make one pre 2005 though.

my bike runs like crap at 3000 RPMS.  Its happy at 5K +

Here's an interesting question for someone: Is it possible that a change of plugs could increase the surging, coughing, hiccuping, bubbling etc etc. that we've all described on this thread if they're not gapped correctly, or if they're a different type?

I went to my local shop and spoke to someone who is very knowledgeable about Ducatis, I bought some plugs that he recommended and installed them without gapping them as he told me not to bother, I assumed sure, why not, it can't damage anything. He never gaps his, finds that they come consistently set and that the stock gap is fine. However now I feel like my bike is doing the 'thing' more frequently and at more rev ranges, never really over 4, but it still doesn't seem 'normal' to me.

I actually talked to him about it before buying the plugs and when the subject of 'normal' came up he told me it's a Ducati, it's never going to run 'normal' haha. I thought that was funny, I've found it to be mostly true too. Oh I also replaced my belts recently but that's all I've done so far.. Any ideas??

When my 695 was acting like that, it turned out I had broken stator bolts, and my stator was floating. As far as the plug issue, I swapped plugs in my 800SS a few weeks ago, gapped them a tad longer, filled it with premium, and really felt the harder pull. Re-gapping DOES make a difference. I also did a 14T front and upped my rear gearing by 2 teeth on my 695 and it really smoothed out the low end for in town cummute driving. Much punchier. Since nobody makes anything for the Euro3 emissions system unless you go with the DP and Termi kit, I also used a small device I got on ebay to fool the temp sensor into thinking it was cooler than it really was and adds a tad more fuel to the mixture. Yeah, it's cheesy, but it worked, sorta....

My S4RS is pretty new as well. I wouldn't call it a stumble at all but it certainly crackles and burbles at certain RPM's. It reminds me of F1 cars when they aren't going all out. To me that's an indication that it's running just fine because a little throttle makes it all go away. I generally just keep it in the higher RPM ranges and even when I'm putting around town it doesn't bother me. I know it's runnng right because a quick twist and the nose is pointing at the sky !!