TPS

Try using the edge of a small chisel and those tits in the center of the torx screws will break right off and you can use a regular torx bit. It worked great for me.

http://www.husaberg.org/index.php?name= ... pic&t=8455


Dale

Now more confusion for me!

I pulled the tank off today (only picked it up on Tuesday) to find the TPS disconnected and the wiring at the TPS block looking burnt. I cant tell yet if it was external heat or heat from an electrical short but when I bought the bike it seemed to run OK.
So do I replace the part or not?

Has anyone tested a bike with the TPS connected or disconnected?

Forgot the sig box.

Blunny said:

Now more confusion for me!

I pulled the tank off today (only picked it up on Tuesday) to find the TPS disconnected and the wiring at the TPS block looking burnt. I cant tell yet if it was external heat or heat from an electrical short but when I bought the bike it seemed to run OK.
So do I replace the part or not?

Has anyone tested a bike with the TPS connected or disconnected?

Click to expand...

i used to run my 650 with the TPS disconnected ..re dale lineaweaver

Whosa what difference did this make to the bike if any...?

it was that long ago i cant remember ... too many :drinking:

I can discern little if any seat of the pants acceleration difference with the TPS connected or unplugged. I did add an on/off toggle switch to the TPS; and I do find that my engine ['04 KTM 525 (540) EXC] seems to run a little smoother down low, which is helpful on technical single track, with the TPS switched off. Perhaps this is due to the decrease in advance caused by of the removal of the additional part throttle advance added by the TPS.

Just taking a wild guess here............

It would seem to me that with the tps not properly "zeroed" the computer would think that the carb was actually running at larger throttle openings, and would therefore advance the ignition to provide more power, when in fact the opposite was true.

If I am not mistaken the resistance through the tps increases as the throttle opens, and thus is telling the computer what position the slide is in.

So, if you just unplug the tps you have an open circuit, and therefore unlimited resistance, I would think that the computer would default to a full advance setting, just like the SEM two map ignitions on the earlier bikes did when you unplugged the gray wire.

I could be talking through my hat here since the two ignitions are different. And the Kokusan and it's corresponding CDI program could have a different default setting.

Like I said in my linked post, someone spent a great deal of time and money putting that tps in the system in the first place.

Dale

I will attempt to convey the essence of what DL told me about the TPS and how it related to Hbgs - I am going from memory and it being what it is ....

In short, the TPS system was designed for small bore multi cylinder engines and it was created mostly to improve fuel mileage at cruise conditions for these motors (steady partial throttle) and it poses some risk to big bore Hbg's.

He went on to say that a 650 Hbg at light steady throttle on a slight uphill (ie under mild load) could approach near 100% volumetric efficiency and with the TPS in place this could produce significant stress on the bottom end bearings.

I believe I have captured the essence of what DL told me - it was a fuel economy effort and is inappropriate on a high performance short range motorcycle, he recommended I disconnect it.

Cheers

Mark

DaleEO said:

So, if you just unplug the tps you have an open circuit, and therefore unlimited resistance, I would think that the computer would default to a full advance setting, just like the SEM two map ignitions on the earlier bikes did when you unplugged the gray wire.

Dale

Click to expand...

When the TPS is disconnected, the engine reverts to the default built-in advance curve. The TPS functions to add advance to the default advance curve primarily at low RPM partial throttle operation much like the vacuum advance in autos. The TPS advance contribution gradually diminishes as the throttle is opened up and RPM increases, i.e. when there is a higher load on the engine in order to curtail detonation.

Ok, I have read all posts for the TPS stuff & I have decided that I will replace my sensor block.
Is it the same FCR as a Yamaha 450? Would the sensors interchange?
I checked bike bandit and the Yam part is $50 US cheaper. Thats a good incentive!