Multistrada 1000 not idling - an ecu based solution.

I had an MTS1000 in for some work, part of which was a service after sitting for quite a long time.  One owner bike, but the owner's recollection of what has happened to it service wise over the years was one of the vaguest I've encountered, and the dash had been replaced twice under warranty so total km travelled was even less clear.  With the current odometer reading around 13,000km, I would assume it had had at least once valve clearance service, but I think that's possibly a poor assumption.

Compounding all this was the fact the bill, in dealing with a heap of other stuff, was rapidly closing on a number around the same as the bike's current value.  Which means I'm not too willing to go digging more than I need to.  On one of these, to get to the bits you need to for a valve clearance adjustment, you start removing the panels at the back, move all the way to the front, remove more bits then remove the tank.  Time consuming, and time is money and the money was running for cover.

So an "annual" service is what it got - fluids, timing belts, etc.  I checked the throttle set up, and that's where it went a bit hmmmmm.

The MTS1000 was the first Ducati with an idle control valve ("stepper motor", etc).  Being a 2003 model, it was also the first with the 5AM ecu, in this instance the 103 hardware version.  When they came out, I recall being told that the throttle opening, as displayed by the diagnostic software, was "throttle opening plus idle control valve equivalent".  So when you check the throttle opening angle cold you might see 4.5 degrees, and hot 3.5 degrees or so.  Confusing at best, but when that's what you've got to deal with, that's what you do.

Any model with an idle control valve doesn't need the air bleeds (the little screws on the sides of the throttle bodies that allow air to bypass the throttle blades) opened, as their primary function is to allow you to set the idle speed.  I also use the air bleeds to equalise the idle mixture between the cylinders, in which case you open the air bleed of the richer cylinder to lean it off to be the same as the leaner cylinder.  Meaning one air bleed should be fully closed, although some variation to that will be discussed later.

On this bike, the air bleeds were both open 1 1/2 turns.  The idle trimmer setting of +29 was also a bit concerning, but given the air bleeds were out that far, the trimmer setting didn't really surprise me.

I don't recall it being overly hard to start and get running when I first started it.  Not for a bike that had been sitting for 3 years anyway - the fact it even fired up surprised me.  As it warmed up I got set to check the throttle body set up and wound both air bleeds fully in to adjust the running balance, then got on to the idle mixture.

I found the mixture quite dirty, by which I mean it had a lot of Hydrocarbons and Oxygen in the sample.  This is usually an indication of richness, so knocking the trimmer back was the obvious thing to do.  Dropping it back to 0 both leaned it out (not as much as I might have thought though) and cleaned it up (not as much as I might have hoped though), but the dirtiness remained.  Sometimes, the best way to fix this is to crack the air bleeds a 1/4 turn.  It's amazing how it can drop the HC and O2.  I suspect it may have something to do with the black carbon crap that builds up around the edge of the throttle blade in its closed position, but when it's a couple of hours work to even check that out, you usually don't.

I ended up at 1/2 turn out on one, and 1/4 on the other for around 4.5% CO.  But the idle control valve didn't appear to be doing what I would expect on restart.  I tried doing the test via the diagnostic tool, but it didn't seem to want to do that.  I pulled the hoses off and blew air through the nipples into the manifolds, and they were clear, and with the ignition off the valve was open so I blew back through the valve into the airbox, and that was clear.  But when you turned the key on the valve went to the fully closed position as it's meant to, but then didn't come out again.  I sprayed some carb cleaner into the outlet nipples, then let it sit for a while, then blew that out and tried some Inox to lube it up and then it would, at key on, close then open again.  Fixed!

Not, as it turned out.  By this time the engine was cold.  With the little valve to manifold hoses back on, hitting the start button got a fire and run at very low rpm for 10 seconds maybe, then stall.  I pulled the hoses off, so it had no obstruction, and at that it idled a little longer before it stalled.  I could see the valve doing a little bit of movement during this, whereas previously it'd been doing nothing at all, and I was thinking maybe it's just too lean with the excessive air leak it now has.

Another trick I try with an idle control valve is to disconnect the valve with the ignition on, then with it disconnected turn it off and on again to make sure it has logged a fault, then turn it off, connect it again, turn it back on and clear the fault.  That can sometimes wake them up to some extent, but not here.

On a previous MTS1000 with an issue like this I had played with the base throttle opening (as in what I did to the SC1000 outlined in the Linear TPS setting report, which, I must say, hasn't really worked since) and tried different ecu files and it sort of ended up ok-ish, without being overly convincing.  But, as above, getting that into this one was not an option timewise.

When you have one of these idle control bikes that won't, one of the first things to do is a TPS reset, the electronic procedure via the diagnostic tool.  And, coupled with that, is making sure the idle stops haven't been played with.  There's a fairly obvious stop easily adjusted just behind the throttle cable wheel on the RH side of the throttle bodies, and fairly obvious tempts those that like to fiddle.  Not a good idea on these, but not uncommonly messed with.  The much less obvious stop between the throttle bodies is very rarely messed with, so you usually have a fail safe there.

So, particularly if the paint is missing, you wind that out and make sure it has no influence.  You can see the throttle opening change on the diagnostic tool if it is an issue.  I've seen winding that previously messed with stop out and doing a TPS solve issues like this before.  I must add, at this point, that I've also seen too tight throttle cables have a similar effect, back to the BMW F650GS days.

Anyway, I did a TPS reset to no effect.  I read the file out of the ecu and flashed it back in again (seen that work before).  Didn't help.  Tried a different file with the same result.  I was thinking I might give a 610 ecu and file a go, just to see if anything changed.

But I thought I'd have a look at the original file anyway.  The specified idle speed is no higher than 1300 rpm, but given it was nowhere near that I thought I'd raise it to 1600, just to see if anything changed.  Also, given that the engine would start then peter out and I've seen that due to not enough enrichment, I got into the start up table and richened the soon after start columns to see if that helped.

Below are target idle speed maps (1 row x 16 temp breaks is how you would define this one), which is measured against engine temperature, for two of the MTS1000 files I have, plus what I tried setting it to.

With the original files, the idle rpm I would have expected to see (if all was going to plan) was 1,300 rpm cold and 1,200 rpm hot.  Keep in mind that I didn't put 1,600 rpm in the target rpm table because I actually wanted 1,600.  I put 1,600 in because I wanted to see if it could do it.  There's no point changing it from 1,300 to 1,350, because it's too small a change to really notice definitively.  Make a big change - if it works, great.  If not, move on to the next thing.

The start up table is a pretty cool thing.  Back in the P7 days, there was only an engine temperature correction table to give enrichment for both differing engein temps and cold starting.  Now that might sound like the same thing, but there's differences in fuelling required based in how cold you're starting from and how long it's been running from cold.  I tended to bump this up a bit on some bikes, so that, at say 5 degrees celsius engine temp, it might have in the range of 40% enrichment to make it light up nicely.  I actually think some of the early 851 start issues, where people would claim the bike was "flooding", were due to not enough enrichment to start, but enough to foul plugs and send it all pear shaped.  Sometimes a bike will crank and not fire from cold, but if you let it sit for a minute or two then try again will start straight up, and I think that's because the residual fuel from the first hit, when added to the second hit, is enough and off it goes.  Just a theory.  I've seen lots of late model stuff - M1000, M1100, Guzzi Breva/Sport models like this.

But, with my 851, I find that if it's a hot day - say 30 degrees ambient - it'll fire then not be so happy because it doesn't have enough fuel to keep running due to the trim at 30 degrees not being enough for a "cold start".  Bump that up and it'll start fine, but then on a cold day it's already up and running by the time it hits 30 degrees engine temp and then it's too rich and gets lumpy as it warms up.

The start up table adds fuel based on rotations since started, and is a decaying enrichment table.  Adds quite a lot more fuel for the first 4 or so rotations, then starts dropping it off in the next 4, etc, up to 2,000 or 4,000 rotations, depending on the ecu.  This first appeared with the 1.6M, and it means the engine temp trim table has much less enrichment - usually in the range of 15% maximum.  But add the start up table's 20 - 30% and it'll fire up and go.

This is why the 1.5M ecu runs rich every time you start them for the first 3 minutes or so.  It was annoying there, but better applied here with the 59M/5AM series.

In this instance I made it 10% richer for the columns of 8 to 510 rotations since starting, which would be the first 30 seconds or so of running.  10% is usually enough to pick them up nicely.

But, none of that shit made the slightest difference.  Well, it smelt a lot more fuelly after I turned it off after a couple of 10 - 20 second poor running start attempts.

The next step was to look elsewhere.  One of my pet loves when trying to make things idle is ignition advance.  As in adding more.  These bikes have a separate idle ignition advance table, a single line map if you like - 1 row, 32 rpm break columns - and with that you can set the advance when the throttle is closed.  As the lowest rpm break point is usually 900 or 1,000 rpm, it's well under the desired / target idle speed and you can usually taper the amount so at 1,000 rpm it might have 15 degrees, but at the rpm you want it to idle at - and here if it has an idle control valve you need to look at the target idle speed as set in the ecu file - you can drop it back to maybe 10 or so degrees, and then the same again at the rpm break above the target idle speed so the idle is nice and stable and not trying to hunt higher as it picks up engine heat, etc.  Meaning when it's cold and not wanting to idle high, the increased ignition advance at the low idle speed will help keep it running.

On old 851SP - 916SP, which have 290 to 300 degrees cam duration at 1mm lift, you can go up to 25 degrees or so advance at idle and the difference can be quite amazing.  Ignition advance really is the best stuff.  I have an 851/888SP2/3/4 eprom that has the break points moved around a bit so it has 25 degrees advance at 1,000 rpm and then 15 degrees advance at both 1,250 and 1,500 rpm.  That way it has a heap of advance to support the low idle when cold, and less at the desired 1,250 rpm idle speed and then not changing for 250 rpm so that the idle speed is nicely controllable.

Anyway, I'm meandering - if you have an idle control valve as the MTS1000 does here, and it's doing its job, then you won't have a low idle speed at cold idle.  Well, you shouldn't, and that was the problem with this MTS.

Some of the files have quite surprisingly low ignition advance numbers at idle, in the range of 0 to 2 degrees.  Not as bad an many of the MV models, which have retard, but still enough to lead to some idle instability.  Part of the table from the MTS1000 file is shown below.

Now, some are possibly thinking that going from 0.5 degrees advance to 15 degrees advance is an extreme change.  Correct, it is, but again it's a case of making a change that is noticeable, and really a change that you want.  I usually use a rule of (preferably) at least 10 degrees advance per 1,000 rpm.  That's a bit ish, depending on what you're doing, but it's certainly a lot more valid than 0.5.  At low throttle opening cruise I'll usually add another 5 to 10.  Some of my revised ignition maps for the late models bikes will see an additional 10 to 15 degrees at low throttle over the original.  For an MV, more.

Given the target idle speed is no lower then 1,200 rpm, the advance under that is somewhat irrelevant as long as the idle speed does what it should.  But if it doesn't, or the engine speed drops under load, it should recover.  With 5 degrees less at 1,400 rpm, there's no chance of the idle creeping up, all else being equal.  The advance above that rpm can influence how the engine returns to idle once the clutch is pulled in, and having it low there gets rid of any holding up issues.  Some of the Guzzi Breva/Sport models would do that, and cutting the advance down a lot would fix the issue.  It's not really otherwise important - there's no actual running condition where the engine needs to support load at 1,800 rpm with the throttle closed.  I did have a 1098R like that at one point - it was an issue with them I was told.  I had one go at it, but I think the owner decided I was a dickhead before letting me have a second try (it can be an iterative process), so I didn't get to fix it.

With the increased ignition advance change, the bike idled happily from cold.  As the engine temp rose, the idle speed started creeping up too, getting to over 1,400 rpm before I turned it off.  That made me realise that the issue previously was it wasn't capable of reaching that rpm.  Why I don't know, as it would have been fine when new like that.  Possibly it had a lot of closing clearance, and the high hydrocarbons could back that up.  But it was much happier now, and a win's a win.  With that, I reset the target idle speed and start up tables back to their original setting, meaning the only ongoing change was the ignition advance at idle.  Well, that and the idle trimmer not being +29 any more, which I would hope had made a decent change to how it ran.

Exhaust design - 2 into 1 versus 2 into 2 on the Ducati 400SS

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Although my 400SS is one of the 20 officially imported into Australia in 1993, I didn't know anything about them until we had a second hand one come into Moto One a few years later, and we all stood and laughed at its slowness.  I did however take the chance to dyno a 600SS once to compare the 2 into 1 header to the M600 40mm 2 into 2 header.  All the 2V Monsters - 400 to 1000 - had 40mm headers std.  When I did the M600/600SS comparison the whole "different bike" thing may have clouded the result somewhere, but comparatively the 2 into 1 600SS (blue) made a little more power under 4,500 rpm and less power above that.  But bike and muffler differences may have clouded that.

So with the 400SS back together I took the opportunity to test the 2 into 1 versus the 2 into 2 that it wore in the Monster.  As to what is the same, well - engine, cam timing, gearing, rear tyre (the same actual tyre), muffler (ever dependable Megacycle).  Different - carbs, carb jetting, exhaust headers.

The 2 into 1 header came with the 600SS when it arrived in 1994.  To help distance it from the 750SS price point wise (the 750SS also gained a second front disc for 1994), it had the 2 into 1 header set from the 350 / 400SS.  The 350SS came with an aluminium wrap black steel muffler like a 750SS (not sure if it was the same part or not) and the 400SS had the aluminium sleeve muffler like the 900SS.  The header itself was smaller in diameter than both the 750 (which was 35mm od) and the 900 (40mm od) and the primary tubes were quite a bit longer.

Photo shows 400SS 2 into 1 on left, M600 2 into 2 on right.  The 2 into 2 features the stamped steel crossover which originally appeared on the 750 Paso and is truly an inspired design for an otherwise complicated part made simple for volume production.  It works a treat.  My 2 into 1 (hereafter known as "original header chopped up into kind of crappy 2 into 1") not so treat filled.

This being the original header chopped up into kind of crappy 2 into 1.  Blue lines indicate the flow path from one header into the other, possibly part of the problem.

The result surprised me a little, given what I thought I might see based on the above graph.  But it also backed up the few other tests I've done with 2 into 1 exhaust.  That being, a 2 into 2 always works better.  Never seen it go the other way.

As to what those other results are, I can think of two of my own.  Moto Guzzi Sport 1100i, where I made a full exhaust for the bike with 2 into 1 and 2 into 2 cross overs.  Otherwise same header and muffler.  Green is 2 into 1.  Had a noticeable top endy feel to it.

And Minne (M600 with a 750 engine) before the valves, cams and comp, fitted with an old Gio.Ca.Moto M600 2 into 1.  43mm od pipe into 48mm od collector, of similar design to the 400SS 2 into 1, but with lots of spring joints, etc.  Red is 2 into 1.

I was also told many years ago that the improvement the Aprilia / Akrappovic accessory 2 into 2 full system brought to the first gen Mille (std 2 into 1 exhaust with the great big muffler) was more midrange.  Which again is contrary to the 2 into 1 myth.

So that's my background to the 2 into 1 thing.  

The graph below shows the 400 engine in the SS with the 2 into 1 in red, in the Monster with the original 40mm M600 2 into 2 headers in green and in the Monster with my original header chopped up into kind of crappy 2 into 1 in blue.  Peak power at just over 80mph is 9,500 rpm.  The 400SS top end air/fuel is an issue, and with more main jet it may make more top end power.  The red curve certainly improved a couple with more air to offset its richness.  The midrange air/fuel is similar to the Monster jetting, so comparatively at least should be similarly crappy.

While the original header chopped up into kind of crappy 2 into 1 did give a stronger bottom end (compared to the 2 into 1 of the green curve it has shorter, larger diameter primaries so it's not following the myth there either), it all went pear shaped over 7,500 rpm.  Realistically, that's about as hard as I revved it anyway, so for me it wasn't a big issue.  But the knowledge that I'd made it somewhat worse annoyed me.  I think it's the way I modified the stamped sheet cross over into the 2 into 1 merge, and maybe the fact that it's all the same diameter isn't helping.  But I'm not inclined to find out and that header set only fits a small block Monster with rear sets so it's a bit restricted in application to play with.

Comparison of the two 2 into 1's below, 400SS is blue.  The funny thing is that the 400SS has a real pick up in performance you can feel around 7,000 rpm.  Maybe it's as the fuelling goes from too rich to too lean, dunno.  Definitely noticeable, whereas the Monster with the 2 into 2, which has a much less smooth dyno curve, wasn't.

Torque and air/fuel shows the taper in the 400SS air/fuel curve that I'm sure you can feel as it gets better (before going to shit).

The jetting also varies a bit - they're kind of wacky.  The 350SS and 400SS std jetting variation is bizarre for what is essentially the same bike, produced at the same time.  The jetting I'm using in the 400 is not quite std.  They use a much softer slide spring than anything else - it's almost like a Factory Pro or Dynojet spring.  I did have them in it when it first went together, but swapped the heavier "in everything else" springs into it to make it a bit richer.  Maybe too rich now, not sure.  Everything except the 600SS use larger holes in the slide with the heavier springs too.  Maybe that transfers more vacuum to the diaphragm.

JD Hord made the comment on Facebook that "I did a bunch of messing around with springs on a Honda Hawk one time, and best I could tell, at steady state they had barely any effect, but throttle response did seem slightly better with heavier springs. I suppose that's because it would pull more vacuum and get fuel moving a bit quicker into the airstream."

It did seem to help the throttle response and starting, but I also richened the idle mixture a bit as well.

The 2001 M400 uses the same spec carb as all the M600, so I ran the original M600 carbs on this engine when it was in the Monster.  The jetting is quite different in those two, but the midrange WOT fuelling is similar on the dyno.  I've got a heap more mindless rambling to do on the jetting stuff, watch out for that blog post - it'll be coma inducing.

Playing with a Ducati fuel level sender

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I put a post on my Facebook page a while ago about Dcuati parts not being covered by warranty if not fitted by an authorised workshop.  The part that prompted that was a fuel level sender I had purchased for a mid 90's 900SS.  The dealer I bought it from did cover it for me, but that was what they were being told.

Anyway, in that case my customer needed a fuel sender for his 900SS as the light wasn't working.  Shorting the terminals in the loom tank connector made the light come on.  Pretty easy diagnosis.  I ordered one in, fitted it, made sure the light was on with the tank empty then put the fuel back in it and made sure the light went off.  It did.  Bingedy boom, Bob's ya f--king auntie.

As it turned out, Bob was an imposter.  The owner called to say the light wasn't coming on.  He came back, I ran the test again as above - no light.  I ordered another sender and when it arrived it was fitted and job done - I haven't heard of any further issues.

Which meant I had this dud sender on the bench.  The dealer didn't want it back, and I tend to keep all this sort of stuff just because connectors, etc, can be handy.  And I was also convinced that when I had fitted it, I'd checked it properly.  But, as with most things that end up on a bench, it had sat simply because I'd had no need to consider it further.

Until Friday, when the 400SS hit the road.  Although I've owned this bike since 2012, its never been near the road as a bike, and there were a few things about it that I didn't know.  Given how much of a dud it was when I bought it (imagine an Ebayer not telling the whole truth!) I shouldn't have been surprised when I realised on Friday, while heading over to see the club man for the permit papers, that the trip meter wasn't doing anything and that I should have been quite a bit through the 5 litres of fuel I'd put in the dry tank after it was painted.  Enough that the fuel light should be on.  I made a precautionary fill up on the way back and put over 14 litres into it without trying, so it was low.

The sender in the bike would most likely be the original, certainly it's the old design.

The current sender to suit the carby SS, 59210161A, is one of the typical black plastic tubes types with the correct eyelets for the fuel pump terminals and is around $330 locally.  As such, I was pretty keen to not have to buy a new one.  Hence my decision to pick up the alleged dud and see what happened.  I plugged it into the connector, turned the key on and waited the 20 or so seconds for the time delay and the fuel light came on.  Result!  Turned it upside down, heard the float go clonk, light off.  Turned it up the right way again, wait 20 seconds, light back on.  Ok.  So what's wrong with it you might ask?  I certainly did.  I figured I might as well fit it properly and see what happened.

59210161A, image stolen from Belt and Bevel, who allegedly have one in stock.

Short answer - what happened was, it didn't work.  Things started well - the light was on when the tank was empty.  But it didn't go out terribly convincingly when it was covered in fuel.  I usually find these things like some sort of vibration to bring the light on - I often do these tests with the engine running or, if not, tap the tank gently repeatedly.  In this instance, that developed into me going it perhaps a little more aggressively than ideal with a long screw driver handle and eventually the light went out.  As anticipated, it didn't come back on when the fuel was drained again, so out the sender came.

Taking a step that I usually don't with a new "sealed" electrical component that doesn't work, I thought I pull it apart and have a Captain Cook.  Nothing to lose anyway.

The top has a small metallic stud sort of thing on top, which looked to me like it might be solder.  Applying the soldering iron confirmed that, and the solder shook off.  The plastic cap turned out to not be retained by that though, it just clips in and out

The solder retains the little steel top hat that stops the float.  Once the solder was gone, it pulled off with a little twisting with pliers.

Taking the float out, it looked to me like it had some ridges at the ends that were maybe jamming, so I put it in the lathe and tried to machine it a little.  In hindsight, I wouldn't recommend doing that at all.  It looked like something hard, but it sort of powdered when I hit it with the tool and it's also soft and doesn't hold too well.  I made a bit of a mess of it, and then wondered if the outer was some sort of sealing cover that stopped fuel getting into the float's foamy cell.  I guess if it does fill with fuel the light will just stay on.  Note to self time.  Undesired result is below.

Reassembled and refitted again, it delivered a similar result. This time, after the sender was covered with fuel, the light just wouldn't go out.  No amount of tapping, etc, made any difference.  In an attempt to move it around a little, I lifted the front of the tank and noticed a heap of air bubbles coming out the two little holes in the cap.  I found that a little odd, so drained the fuel and removed the sender again - this time keeping it upright hoping what was wrong inside it might not change.  When I popped the little cap out, the float was up and the unit was still full of fuel - an obvious problem.

The reason that's an obvious problem is because there's a hole in the side.  Well, there's meant to be.  Looking at the "hole" in the side a bit harder I realised that the drill hadn't been leant on hard enough.  

Leaning on a 2mm drill a bit harder, I got this:

With that, I reassembled and refitted again with supreme confidence, confidence rewarded with a fuel light going off then coming back on with variations in fuel level.  Woohoo!  Fixed.

Of course, I then re-entered the living hell of getting the fuel cap carrier rubber surround ring back in place.  When I reassembled the tank a couple of weeks ago I finally managed to stretch the rubber enough to get it to stay in place long enough to jam it into the top of the tank.  This time, I gave up and borrowed a pair of hands.  I haven't done that for at least 11 years.

All I have to wait for now is my molested float to fail.
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