Disclaimer -
The following worked for
my bike.
I am a mechanic, but I'm not a dealer, nor am I Husky trained.
I've gone from 5-10 flameouts per days ride to just
ONE in the last 2 rides still with a factory ecu!
About my bike -
- 2011 TE449 bought new 08/2012.
- Supplied Akro slip-on & jumper plug fitted from new at the dealer.
- Everything else standard until dealer updated map to the AKRO racing exhaust map.
- Rode (rather than towed) my bike home from the dealer to put some easy Km's on it,
removed the huge number plate holder & mirrors & when to the local marked trail to run it in.
(The track has several big hills & some fast open trails.)
- The bike stalled several times & the idle stayed high a couple of times.
- Took the bike home & adjusted the idle screw, still ran the same.
- Took it to the (BMW) dealer, they 'made some adjustments' & said it was fine. (It still played up the same)
- I started to try things myself & make adjustments. Some for the better, some for the worse, over about 6 months.
- I tried all the 'resets', idle screw set at the magic no. of turns etc, no change.
- Just prior to the 12 month warranty expiring, I took it to another local dealer (Berg & Husky) for them to check it out & left it there for a couple of weeks.
I was told they reset the TPS adjustment, reflashed the ECU, swapped ECUs with another bike (which is still in it as the VIN no. on the sticker doesn't match my frame now) Replaced the spark plug, checked the valve clearances, cleaned the earth & terminals etc.
- It ran well for half of the first ride until I stalled it on compression & then had the 'hard to crank over' thing they do, lost the data from the trip meter & clock.
From then on, it returned to flame-outs & erratic idle.
- I replaced the battery with a Lithium one with 90 more cranking amps & the dash now keeps it's memory.
- Went through resets & idle settings again & again, no change.
- I had also noticed if the throttle was just cracked off idle, the revs increased, but it sounded laboured (fuelling not correct)
- I had also put a fair bit of thought into why it flames-out sometimes & not others.
I
believe the Fly-By-Wire 2nd throttle doesn't open quick enough at times when you crack the manual throttle, so the ecu sees the throttle open, dumps in the fuel, the FBW plate is still partially closed so not enough air arrives & cough, flameout.
What can I do about the FBW throttle?
- My original plan was to get the ECU for a
TC449 as it doesn't have the second throttle & modify the harness to suit - N.G., too hard.
- You can't remove the FBW throttle set-up. as the ECU 'looks' for the motor & 2nd TPS.
So I stripped the air-cleaner out of the bike & removed the FBW throttle plate & screws from the shaft.
As far as the ECU knows, it is still running the show, all it is doing is turning a shaft & making sure it is where it told it to be via the TPS
I still have control of the cable throttle, and the ecu sees the 1st TPS signals as normal. All good.
View attachment 39047
View attachment 39048
What about the hanging idle?
- Obviously the ecu is not capable of making any sort of decisions about idling!
I stripped the throttle cable cover off the throttle body, removed the cable cam from the shaft & removed the arm from the manual throttle section. (This is the arm that the FBW throttle lift & lowers to control idle) Now the ECU can turn the shaft all it wants & not idle the motor high & spit me off into the trees every second time I ride it
I set the idle speed off the brass idle screw exactly how the
TC is done, simple
I have left the brass spacer behind the cable cam & made a plastic guide for the throttle spring to run on (As the arm has a 'cup' for the spring built onto it)
I also took a measurement of the factory gap for the set screw(yellow paint in picture) in case I fell the need to refit it later.
View attachment 39049
And the dead spot off idle?
I decided to play with the TPS adjustment after finding other Keihin bikes are very picky about the idle output voltages (Most 0.45 -0.6)
It is pretty difficult to get at the pins on the TE449 to actually measure the voltage, so I decided to crack the TPS screw & move it just a bees-whisker in the direction of acceleration of the throttle shaft.
As I moved it slightly, the idle smoothed out & now transitions smoothly to cracked throttle.
Over-all, I'm stoked at the changes.
No more driving over the 'bars into that creek bank or log you just tried to pop the front wheel over when it flames out.
No more spearing off the outside of a corner after you expect 450cc engine-braking &
get 125 2-stroke engine braking instead.
And, I haven't bought an aftermarket ecu & had to tune it, fiddle with it and deal with extra wiring in a crowded frame. I ride all sorts of terrain, mud, beach, rain, creeks, dust, I didn't want non-factory wiring & plugs in that.
Hope this helps someone else, as I've mentioned at the start, it worked for my 2011 model.
It may not do anything for someone elses bike.
