DIY fuel trim with VDST, etc

[booger]

My bike's a 2006 S2R800 with the 5AM DP ECU. I will need to do the valves soon, and after that I'm seriously thinking of using the VDST software, a twinmax throttle body synchronizer tool, and a muffler sniffer. I have a friend with the twinmax, another friend with the CO analyzer, and I'm going to buy the VDST. My reasons for doing this are choppiness in the power delivery from 0-4k rpm, surging, and popping through the airbox (also DP). Catless midpipe, Termi slipons, 5800 miles on the bike, original Champions had a nice gray powdery coating. Changing to NGK Iridiums yielded barely noticeable gain in smoothness, popping through the airbox has become louder and sharper, more like a backfire. I can't stand it anymore! It usually chokes up after being run below 4k for for longer periods like when navigating through city traffic. Stop at a light and wait a few moments. When moving off the airbox farts a couple niffs and the bike hesitates. Idles at 750-900rpm. I think this bike needs a tune.
I have the LT Snyder book, the factory shop manual, and the above tools. Am I going too far? I'm superannoyed at the way the bike has been running. Don't want to take it to a dealer, I'd rather do it myself. Has anyone here had any success using the VDST, or the Twinmax, or the Gunson Gastester or similar items on their Monster FI? It seems like with these three items you can pretty much do everything the DDS can. What does the VDST not do?

[EEL]

Valves are off.. If you fix them your problems should go away. Plus sync can hurt.

No real need for VDSTS in my opinion.

[Howie]

Don't forget to check TPS.  Do check for vacuum leaks also.

[scott_araujo]

I had similar problems with my '03 800, totally stock.  I got VDSTS.  A proper tune including new plugs, valve clearance, TPS reset, fuel trim set, idle speed set, and throttle body synch made it behave very nicely.  You don't always need a PC3 to make a stock engine run well.

That said and your engine not being stock, start with the vacuum leak check, valves, and the TB synch.  You can do those without VDSTS.  See how it runs.  Also, you should be idling around 1200.  There's a sticker under the seat with the exact spec for your bike.  If the valves and TB synch don't bring you into smooth running then the next step is a full tune as mentioned above.  It's a lot of money for the tools but less than most first services cost at the dealer.

Also, I got the Gunson ColorTune spark plug to set the idle CO.  It's way cheaper than the gas testers but less convenient, you have to swap it between cylinders and can't run it for mor than 5 minutes in an air cooled engine.  Now I don't even use it, just set it by ear the way I used to with the idle mixture screw on carbureted engines.

Scott

[RB]

The only issue i see so far with your above mentioned method would be the gas analyzer. I i am correct, you are only going to be messing with idle using the analyzer, unless you have a dyno, or you carry the analyzer with you, have some data logging software tied into the analyzer, tps, and tach(rpms)....which i doubt.
Since these bikes carry 'maps' in the ECU, throttle position combined with RPM will deliver a different fuel delivery throughout the range. The gas sniffer makes sense to purchase, and is more accurate when tuning then an AFR(air fuel ratio). But i haven't seen an affordable gas sniffer that will data log so that you could ride and tune. If you do the sync and valves, that will definitely help smooth out the bumps you are complaining about. Yes you can get your bike to run better without a PCIII, but with the mods you added, and possibly plan to add, you may need to adjust the fuel map for optimum performance.

[booger]

Thanks. The shop manual states all bikes are to be set lean at 1.5% CO Vol to meet antipollution standards and between 4 and 5% for best performance 'when racing'. I'm assuming they are stating this based on the stock ECU. Further research and threads on the subject in other MC forums has all come up with 4-5% as the desired CO, regardless of bike.
So first I'll adjust the valves and rule out any vac leaks, second sync the TBs, and third reset the TPS and see how the bike runs. After that if needed I'll sniff the exhaust and trim the CO. Should be a fun project. The only thing that concerns me is that the DP module might be mapped lean until 4k, and I can't adjust them, all I can do is set idle CO. There might be a PCIII in my future but if after setting the valves up and doing everything I can do without dynoing it with a power commander yields a good result I'll declare victory. I'd like to get more smoothness out of the lower range and get rid of the flat spot from 0-4k.
Now for the vac leaks- am I just checking around the throttle bodies for cracked rubber hoses or what? How many points are vulnerable to leaks and where are they? Thanks for the info.

[scott_araujo]

The CO trim is not just idle, that's just where you set it.  It's a set amount of time added to every injector pulse width through the entire map.  It matters everywhere, it just matters way less at WOT (large pulse width) than it does at low throttle openings (small pulse width).  For me it made a big diff below 4k at around town speeds/throttle openings.  Go to Brad Black's Moto One site and read his two articles on how fuel injection works if you want the nitty gritty.

I think the DP ECU is a 'racing only' part so doesn't care about EPA emissions at low revs.  Set to 4-5% at the tail pipe or around 6% at the header bung and you'll be in the neighborhood.

Oh, and I think you need VDSTS or something similar to reset the TPS unless you get it done at the dealer.  Some dealers are friendly and will do it for cheap.  If you get the software and do it yourself, you're already in the ECU, may as well set the idle trim too.

Scott

[billg69gmc]

My only thought is have you thought of adding the FatDuc Manipulator to sweeten up the low revs? I'm very pleased with it and tie that into your other service thoughts and you should have it back to 100%.

[booger]

My only thought is have you thought of adding the FatDuc Manipulator to sweeten up the low revs? I'm very pleased with it and tie that into your other service thoughts and you should have it back to 100%.

I don't think the FatDuc will work with my bike - I thought it was for the O2 sensor equipped engines. I have the 800cc non-O2 bike.

The only issue i see so far with your above mentioned method would be the gas analyzer. I i am correct, you are only going to be messing with idle using the analyzer, unless you have a dyno, or you carry the analyzer with you, have some data logging software tied into the analyzer, tps, and tach(rpms)....which i doubt.

Yep, I'll be setting fuel trim (CO) at idle, trimming up or down on the VDST to achieve between 4 and 5% CO as indicated by the sniffer. That's the best I can do and should work out fine. After all of this, I'm confident that the worst of the symptoms will be eliminated. The only thing I'm not counting on is totally fixing the flat spot below 4k. That may be permanently mapped in the ECU. To really supertune the engine a PCIII and some quality time with a Dynojet machine is required. What I'm trying to do is tweak what I've got for now, and see what happens.

[billg69gmc]

Ahh, I see. Sounds like some good old school tuning would be in order.
Hope you get things sorted.

[brad black]

My bike's a 2006 S2R800 with the 5AM DP ECU. I will need to do the valves soon, and after that I'm seriously thinking of using the VDST software, a twinmax throttle body synchronizer tool, and a muffler sniffer. I have a friend with the twinmax, another friend with the CO analyzer, and I'm going to buy the VDST. My reasons for doing this are choppiness in the power delivery from 0-4k rpm, surging, and popping through the airbox (also DP). Catless midpipe, Termi slipons, 5800 miles on the bike, original Champions had a nice gray powdery coating. Changing to NGK Iridiums yielded barely noticeable gain in smoothness, popping through the airbox has become louder and sharper, more like a backfire. I can't stand it anymore! It usually chokes up after being run below 4k for for longer periods like when navigating through city traffic. Stop at a light and wait a few moments. When moving off the airbox farts a couple niffs and the bike hesitates. Idles at 750-900rpm. I think this bike needs a tune.
I have the LT Snyder book, the factory shop manual, and the above tools. Am I going too far? I'm superannoyed at the way the bike has been running. Don't want to take it to a dealer, I'd rather do it myself. Has anyone here had any success using the VDST, or the Twinmax, or the Gunson Gastester or similar items on their Monster FI? It seems like with these three items you can pretty much do everything the DDS can. What does the VDST not do?

all the stuff you mention is just part of any service.  it should be anyway.  reset the tps - you can check if it actually changed by reading the throttle degrees with the fast idle pulled on, then after the reset pull the fast idle on again and see if it's more then 0.2 or so different.  then start it, balance the throttles by checking between 2 to 6,000 for the best compromise (compromise often being the main word) with the air bleeds screwed fully closed, then set the idle speed with the air bleeds then set the idle mixture with the gas analyser and vdsts.  check each header individually if possible (1/8 gas fittings needed for header ports) and use the air bleeds to get them both the same.  i'd go for 4.5 - 5% CO.

the idle mixture setting is a "reference" setting - it affects the whole map, but low throttle much more so.  it's the only reference there is for the ecu fuel mapping, and theoretically should make it right.  right meaning as the people who mapped it intended, who's version of right may differ from someone elses.

vdsts can't reflash ecu, and has no self diagnosis capacity or wiring looms or other specific stuff.  but it does most stuff you need for service.  could make it a different bike, and it should run nice enough with the dp ecu.

[booger]

Cool, thanks Brad.
One thing I should note- I just didn't want to get on the bike with it farting at stoplights and I'm not fully set up to do all the work right now(weather is awesome today), so I decided to do a little fiddling with the air bleed screws and watch for an appreciable difference. I marked their positions on the manifolds with a Sharpie and turned them both one quarter turn clockwise. The farting through the airbox is gone, and the idle has come up about 100 rpm. Moving off is less choppy. Surging is still there to a degree. However the bike is rideable. So- what I'm going to do is enjoy another couple hundred miles until 6k then bust out the tools and get to work [moto]

[scott_araujo]

What you did basically made it a little richer.  I'd bet that if you do a full tune with VDSTS you'd probably be running just fine.

Scott