[GytRDunKat]

Dude, you need to find a different line of work. I don't know what you make, but it should be 3x what your making now. I would suggest one of the big 3 automakers, but that gig just might not work out. You need Monster.com or something... Sheesh!!


You've missed your calling dude, go find it again! It's calling, and IT don't know your number. This was like a mosqito in the net for you. Go get em tiger!

[TheSteve]

Lol yeah.. being 20 and working at a movie theatre isn't a whole lot to brag about.. Gotta go back to school first, then hopefully I'll be doing something a hair more interesting than fixing projectors.

[TheSteve]

Well, its been quite awhile since I've last posted so I figure I'll give you guys a small update.

I believe I'm about done tuning, as every time now when I go out to tune the numbers change by less and less. The bike rides like a factory original to the point where I'd have no problem loaning it to someone for a few days (as in I wouldn't worry about it leaving them stranded). Power is very linear, no coughing or choking, usually starts on the first crank, etc etc. Mileage has been right at 45-48MPG throughout the winter. I'm not sure if the decreased mileage is from the cold or my riding style. Having just started riding maybe 7 months ago, I'm sure I started going faster now that I've gained comfort with the machine. In addition, not a day goes by where it doesn't get up to 85-90MPH on the freeway. Were I to actually maintain speed limits I'd likely be back up to 55+MPG. Might be worth a tank of gas to see if mileage goes up if I slow down.

I still have the occasional problem starting, but I'm beginning to think it isn't entirely the fault of the Megasquirt. Left to sit for a few days (especially when cold), sometimes it'll crank, fire, run for 3 seconds or so, and die. Then it'll refuse to restart without the aid of a car battery. My only guess is the afterstart enrich is fouling plugs and it really needs HIGH voltage to arc across them till it gets going. Not sure theres much I can really do there, because if I lean it out it'll die on its own, and any richer and it tends to flood. It's not a big issue unless its really cold outside.

I feel pretty confident in the current state of tune though, and am about to pull the wideband out to begin retuning my MS'ed truck, whos mileage went south without the wideband to guide it. The Katana, on the other hand, was set to NOT rely constantly on the wideband. Meaning once unplugged it should get the same mileage and same throttle response. I don't plan on replacing it with a narrowband O2 sensor. In my opinion they are a complete waste of money, especially since my tune rarely sits at 14.7:1 AFR. Instead itll be replaced with a simple threaded block off plug allowing for an easy reinstall later if needed.

So, has anyone else made any progress on their EFI Katanas? Post up!

[Adequateman]

Might be worth taking a wire brush to the plugs. Or replace them, if they are old.

[ericej2344]

Even though its a small problem, let us know if anything changes with that cold start bug.

[TheSteve]

Time for a small update. The wideband has been removed from the bike and it still runs as well as ever. I did not install a narrowband sensor, instead I just blocked it off. Since it still runs fine with no o2 correction it means the maps are spot on.

I've been pondering the startup issue and I think I've figured it out. The bike only has issues on hot starts, like after parking after sitting in traffic then trying to start it back up 5 minutes later. So the engine is probably borderline overheating. As you know, these oil cooled engines already run hot. Overheating means the engine is probably pushing 350 to 400 degrees. The megasquirt, due to limitations in programming (max value for integer storage is 256), can only understand temps up to about 215. This is because the code is set so the min temp is -40. After a hot shutoff, the engine is well above that 215 mark, but the MS thinks its no higher than 215.

The ms bases starting injections on temperature, so since a hot engine needs less gas to start, the 350 degree motor floods when given the gas it'd need at 215.

The solution is to bump up the minimum temperature that megasquirt can see. I live in Arizona, so if I can push the min temp to +40F that should raise the max temp to almost 300F which should be good enough for these hot starts. To do this id have to make changes in the MS code itself I think. I don't know how to do this, but I'm going to check the ms forums to see if its possible. Ill keep you updated as I find out more.

[ericej2344]

sounds interesting, let us know how this turns out.

[TheSteve]

After not getting much help on the MS boards, I'm thinking of a different way to achieve the same result. The MS lets you specify a resistance curve so you can use a custom sensor. If I use my current sensor but change the data points, it could read 350F but report something totally different but not maxed out. Right now if the engine is 200, its reported to the MS as 200 but itll top out at 215. Changing the curve could make it so if the engine is 200 it reports 90 (for example), and it would effectively top out at 325 while reporting 215. I'm sure there are some ill-effects from this, but I think it should work just fine. MS only uses the coolant temp for warmup and cranking so it may give it the boost it needs without hurting much else.

One of the crappy things about MS1 is that the crank pulse temps are preset (with a 160F max) and cannot be changed. With MS2, you can generate your own startup curve with temperatures up to the full 215. What this means is that to MS1, for cranking 130F = 130F, 160F = 160F, but 180F+ = 160F. For MS2, since you set the temperatures to whatever youd like you dont hit that limit.

What this means is that to make this start an engine accurately, I'd have to drag the CLT values down to maybe 180 degrees at the absolute most while HOT. A possible problem with this is that the engines cold temp might be south of the established minimum of -40f and then instead of hotstart problems I'd have coldstart problems. This problem would be helped by use of the MS2 since the values would only have to be pulled down to 215 instead of 160.

Theres also the possibility that I could set the sensor curve so that -40 (sensor) = -40 (MS) but 350 (sensor) = 160 (MS). That might create a pretty funky looking curve though leading to all sorts of weird startup issues.

This is all theoretical at this point, I haven't done anything other than post up on the MS forums yet. I'm moving tomorrow so it may be some time before I have a chance to really play with it. Couple that with the bike being my daily driver I'd rather not accidentally make it worse on a day where I need to be somewhere.

[il_ragazzo]

im so glad you are doing this first! i get to learn form your mistakes

[TheSteve]

Its been a good week for the katana. I adjusted the resistance values in the megasquirt to aid in hot starts and it seems to have helped quite a bit. I have not had the chance to try it in an overheat-start but I'm hopeful that it'll work based on how well its been doing lately. I also finally repaired, sanded, and painted the kat so its no longer quite as big of an eyesore. Ill post pics once I get home.

Anyway, I set the resistance curve for the existing temp sensor so that at -40f it still should read around -40, but now the max temp it'll read is about 300. Of course I had to retune crank pulsewidths, warmup enrich, and afterstart enrich to match the new table but it seems to work pretty well. Now at 40f it reads somewhere around -7f so there's plenty of resolution in the upper end. Swapping to an MS2 would help this further but it seems unnecessary at this point.

So now with the bike starting more reliably and being less sinfully ugly it seems the project is coming to an end until I again find something stupid to do to it.

[TheSteve]

Here are the pics of how the fairings came out:





I'm pretty satisfied with how they came out. The only issue is it makes it more difficult to work on if and when it needs it. I can still get to the idle screw so thats ok, but it doesnt have clearance to plug in the laptop without taking off the left side tail fairing. Oh well.

[Black_peter]

Too bad you can't show it off... With the fairings on it looks stock.

[Kreylyn]

Too bad you can't show it off... With the fairings on it looks stock.

Sometimes those are the best... I love a good sleeper.

Krey

[il_ragazzo]

me too

[airforceranger49]

quick question for you bro... how much did this really wake the bike up... i mean is it like a whole new bike, or is it just a subtle difference?