Suzuki Burgman USA Forum banner

1 - 14 of 14 Posts

·
Registered
Joined
·
35 Posts
Discussion Starter · #1 ·
Hellò,
I am looking for some info about the sensors of speed and coolant temperature.
Do you know if there is a simple way to retrieve the values of those sensors? I mean a way that does not need to disassembly half scooter :wink:
I am thinking to try to trick the Ecm in order to slightly increase the rpm when the speed goes under 35Km/h and then reducing the engine braking at low speed.
Below that speed, I would like that the Ecm believe that the engine is cold (through the coolant sensor I suppose) and then starts the automatic choke increasing the rpm.
What do you think about it? Do you think that could be feasible or is only a strange idea?
thanks:eek:ccasion5:
ciao
 

·
Registered
Joined
·
735 Posts
Buon giorno. I had all the front-end "tupperware" off the bike last year, and I "tapped into" the wiring for the intake-air temperature (IAT) sensor and speed sensor. My goal was to build my own speedo healer and air temperature display. To do any playing with the signals you have to break the wires to the ECM I think.

I don't think playing with the coolant temp sensor (ECT) will change the engine braking but you can always try and then tell us what happens!

I wonder if anyone has tried the "brute force" method to change the CVT ratio? That would be to control the voltage to the CVT motor yourself. I'm sure that the ECM would immediately start throwing FI codes but it would be an interesting experiment. I don't plan to try it on my 650. A presto!
 

·
Registered
Joined
·
35 Posts
Discussion Starter · #3 ·
Buon giorno. I had all the front-end "tupperware" off the bike last year, and I "tapped into" the wiring for the intake-air temperature (IAT) sensor and speed sensor. My goal was to build my own speedo healer and air temperature display. To do any playing with the signals you have to break the wires to the ECM I think.

I don't think playing with the coolant temp sensor (ECT) will change the engine braking but you can always try and then tell us what happens!

I wonder if anyone has tried the "brute force" method to change the CVT ratio? That would be to control the voltage to the CVT motor yourself. I'm sure that the ECM would immediately start throwing FI codes but it would be an interesting experiment. I don't plan to try it on my 650. A presto!
Hi Mike and thanks for your comments.
I would like to do something very similar to your idea, the goal is different but the concept is the same.
We both want Ecm or Cvt forced to do something different, and I agree is not a simple thing but very interesting.
I could initially start by inserting a tester on the ECT sensor and collect the voltage when cold and when hot. Then, when engine is hot, try to disconnect the sensor and insert the same voltage level that sensor retrieved when engine was cold and, of course, see what happen!!!
Could you tell me where is located the Ect? May be the first step could be more simple than it seems.
ciao
fausto
 

·
Registered
Joined
·
735 Posts
The ECT is in the cylinder head, underneath the right-hand intake port. You might be able to work on it by removing the "maintenance lid" but I don't know for sure. Buona fortuna!
 

·
Registered
Joined
·
2,935 Posts
I've described a hundred times my proven way of reducing engine braking, by using a SpeedoHealer to let the CVT-controller think you're going faster than you actually are.
 

·
Registered
Joined
·
35 Posts
Discussion Starter · #6 ·
I've described a hundred times my proven way of reducing engine braking, by using a SpeedoHealer to let the CVT-controller think you're going faster than you actually are.
Hi Erik, I'm happy to read you again.
Yes, I remember we discussed about speedohealer some months ago but I don't like it, even if I'm sure it can be really effective.
Speedohealer can Cvt-controller think that I'm going faster then really and it's good when decelerating, but on the other hand, while accelerating changes gear too soon and I don't like it at all..
I think that when the engine is cold, the engine braking is almost perfect and it could be usefull to replicate the same situation even if the engine is hot and speed is low.
However, you help, comment and suggestions are always appreciated.
grazie, ciao
fausto
:eek:ccasion5:
 

·
Registered
Joined
·
2,935 Posts
My guess is that enriching the fuel/air mixture on a warm engine will make it run rough and slower.

It really is no problem that the engine upshifts sooner, you just turn the throttle some more, and it will upshift later.

Unless you are racing against an other AN650, it makes no difference.
 

·
Registered
Joined
·
35 Posts
Discussion Starter · #8 ·
My guess is that enriching the fuel/air mixture on a warm engine will make it run rough and slower.

It really is no problem that the engine upshifts sooner, you just turn the throttle some more, and it will upshift later.

Unless you are racing against an other AN650, it makes no difference.
"My guess is that enriching the fuel/air mixture on a warm engine will make it run rough and slower"
You're right Erik, but with this "workaround", fuel/air mixture will be enriched only when you are decelerating and then, with the throttle completely closed, so I immagine that there will not be any problem...even if my supposition. :rolleyes:
It is only another idea, the best solution, (after the own wrist) is still the speedohealer that you suggested.
ciao
:)
 

·
Registered
Joined
·
35 Posts
Discussion Starter · #9 ·
first try has gone.
well, I tried inserting a variable resistor in place of the ECT sensor. I needed a variable resistor in order to simulate a cold engine with a 2,45Kohm resistance and then a hot engine with a 0,3Kohm resistance.
FI blinks probably due to an incorrect voltage detected by the ecm…I'm sure it can be fixed.
On a warm engine, the 2,45Kohm resistance force the Ecm to work as if the engine is cold. So the rpm is a little increased and the more is the resistance, the more the rpm are increased. At 5Kohm rpm are about 1.600-1.700rpm. Lower than 1Kohm rpm goes below 1.000rpm.
With the 2,45Kohm resistor engine braking is significantly reduced. At around 30Km/h, closing the trottle I've heard a little engine braking but after that the engine seemed to decelerate more smoothly up to stop. It act like you keep the trottle slightly, very slightly open.
I felt the same behaviour on my old Honda Silver Wing 600, when the clutch went off below 2.500rpm.
The try have been very interesting, I think that I need further evidence and test, perhaps with fixed resistor and then study which is the sensor to use in order to insert and remove automatically the 2,45Kohm resistance. I am thinking on Speed Sensor or Trottle Position Sensor.
At last, I am looking for some other info concerning the "deceleration signal" described in 6-10 of the manual. I'm sure that this is the main cause of the engine braking. If we could intercept that signal, maybe we could reduce the braking... For those who don't like it, of course ;-)
Thank you for your patience to read, for your comment and suggestion.
See you soon
ciao
fausto

P.S.: please, apologize my english :)
 

·
Registered
Joined
·
35 Posts
Discussion Starter · #10 ·
first try has gone.
well, I tried inserting a variable resistor in place of the ECT sensor. I needed a variable resistor in order to simulate a cold engine with a 2,45Kohm resistance and then a hot engine with a 0,3Kohm resistance.
I have found an interesting article on what I am thinking to do. That is exactly what I had in mind to try to reduce the engine braking.
I have in mind to use an "Arduino Uno" to drive a relay and a Gps shield to detect the speed and between 5Km/h and 40Km/h it will insert a 3Kohm resistor on the Ect to simulate a cold engine and increase the ignition time.
It should works for about 60€.
http://www.autospeed.com/cms/article.html?&A=112726
ciao
 

·
Registered
Joined
·
1,034 Posts
So to me this should fix the jumpy feeling you get when you try and go from fast to slow with the engine braking. Seems interesting. I wonder if it would help or hurt gas mileage?
 

·
Registered
Joined
·
35 Posts
Discussion Starter · #12 ·
So to me this should fix the jumpy feeling you get when you try and go from fast to slow with the engine braking. Seems interesting. I wonder if it would help or hurt gas mileage?
I think that it will not hurt gas mileage because of the small range where the ignition time is increased.
However, it is simple to solve. You could use the Throttle Position Sensor and let Arduino insert the 3Kohm resistor only when the throttle is closed or use a Hall effect switch on the throttle, but imho is less accurate then the Tps level.
ciao
:)
 

·
Registered
Joined
·
2,935 Posts
Interesting. Since I've dealt with the obnoxious engine braking by chanhing the speed signal to the CVT, I'm more interested in improving the fuel economy by tricking the ECU to think the intake air and engine coolant is hotter, since fuel economy is vastly improved at hotter temperatures, much more so than in my cars.
Sadly my programming skills are lousy, otherwise I have several ideas that can only be realized using an Arduino or similar device.
 

·
Registered
Joined
·
35 Posts
Discussion Starter · #14 ·
Sadly my programming skills are lousy, otherwise I have several ideas that can only be realized using an Arduino or similar device.
Hi Erik,
Try a search for "scooterputer" and you will see an interesting project with arduino. It is really amazing.
Ciao
 
1 - 14 of 14 Posts
Top