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Trim pots........

Joined Jul 2007
3K Posts | 0+
West Lothian, Scotland
Guys........can anyone tell me which adjuster on the ecu affects which exhaust? Setting co2 levels tomorrow. cheers
 
Brilliant Col, thanks bud.......is that as you sit on the bike mate??

Yep as if you were sitting on it

As you look at them looking back from the front of the bike the rear cylinder is the trim pot nearest the ecu connectors.

Keep the engine temp below 93 degrees as the ecu richens the mixture to aid cooling at that temp and it will mess up the reading. I feed a fan into the rad and stop adjusting if the rad fans kick in.
 
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Yep as if you were sitting on it

As you look at them looking back from the front of the bike the rear cylinder is the trim pot nearest the ecu connectors.

Keep the engine temp below 93 degrees as the ecu richens the mixture to aid cooling at that temp and it will mess up the reading. I feed a fan into the rad and stop adjusting if the rad fans kick in.

Brilliant Colin, thanks for tips!! I'll set the fan up in front before I start.......top man:thumbup
 
Sorry to hijack your thread Andi, but I gotta do the same on mine tomorrow to bring down the idle speed.
Which way do I turn the adjusters to do that?
 
Sorry to hijack your thread Andi, but I gotta do the same on mine tomorrow to bring down the idle speed.
Which way do I turn the adjusters to do that?

Start with the idle adjustment screw wound not fully bud. Have you vacuum guages and co2 reader? Once fully warmed bud, check the levels and if needed turning the air/fuel screw clockwise decreases revs but will alter the mixture so a fair bit of tweaking is needed to get all spot on! Took me about an hour to get 3.5% front and 4%rear with the correct vacuum cv the throttle bodies!
 
Start with the idle adjustment screw wound not fully bud. Have you vacuum guages and co2 reader? Once fully warmed bud, check the levels and if needed turning the air/fuel screw clockwise decreases revs but will alter the mixture so a fair bit of tweaking is needed to get all spot on! Took me about an hour to get 3.5% front and 4%rear with the correct vacuum cv the throttle bodies!

I don't understand a word of that!
Closest I have to any of that is a vacum cleaner, it's a Dyson though, will that do? :p
Heard about the idle adjustment screw. gonna go have a look and see if I can find it.
 
I don't understand a word of that!
Closest I have to any of that is a vacum cleaner, it's a Dyson though, will that do? :p
Heard about the idle adjustment screw. gonna go have a look and see if I can find it.

Ha!! The idle adjustment screw is on the right hand side, just below the fuel tank, and connects to the throttle bodies bud. If the bike is just idling slightly high, turn it (once warmed up fully) anti-clockwise to reduce the speed. Let it settle and blip the the throttle a couple of times and see where it sits then. Best to take it for a run to check but the roads are still crap bud. The rest of the reply is based around adjusting the co2 and vacuum settings on the throttle bodies bud, so you don't need to worry about that, my mistake bud!!!
 
Ha!! The idle adjustment screw is on the right hand side, just below the fuel tank, and connects to the throttle bodies bud. If the bike is just idling slightly high, turn it (once warmed up fully) anti-clockwise to reduce the speed. Let it settle and blip the the throttle a couple of times and see where it sits then. Best to take it for a run to check but the roads are still crap bud. The rest of the reply is based around adjusting the co2 and vacuum settings on the throttle bodies bud, so you don't need to worry about that, my mistake bud!!!

thanks for the help. Sorted the idle speed via the screw. Didn't know they changed it to a knob that attatches to a lil bracket on the frame, was wondering what that bracket was for on the new frame.
Must remember though, next time I take the bike apart to re-attatch the fuel return pipe when I run the bike. Was wondering where the petrol was coming from...
 
Can anybody tell me what the correct adjustment for the trim pots on the ecu is and also i have a A63KAT chip installed is that a gud chip
 
Can anybody tell me what the correct adjustment for the trim pots on the ecu is and also i have a A63KAT chip installed is that a gud chip
Vary from bike to bike

Read this

Try Gabros baselines from http://www.apriliaforum.com/forums/s...ke-with-an-EGA
"set the bypass brass screws (TB's left side):
-> 51mm ad 54/57mm TB's generally needs different air bypass set-up: so try rear screw to one turn out from closed, front screw 1.5 turns out fronm fully closed for the bigger TB's, 2 turns out rear and 2.5 turns out front for the 51mm tb's.
Anyway that's only a base point. If the bike can't idle with the screws so closed, try openup 'em more. Try to keep the motor un-balanced with the front cylinder stronger than the rear.
7) set the ECU trimpots both to zero position at 12 o'clock (the one near the ECU connectors is for the rear cylinder). Try to run the pots around that position, if you have to go far away on the rich or on the lean side maybe there's a problem elsewere."
 
Vary from bike to bike

Read this

Try Gabros baselines from http://www.apriliaforum.com/forums/s...ke-with-an-EGA
"set the bypass brass screws (TB's left side):
-> 51mm ad 54/57mm TB's generally needs different air bypass set-up: so try rear screw to one turn out from closed, front screw 1.5 turns out fronm fully closed for the bigger TB's, 2 turns out rear and 2.5 turns out front for the 51mm tb's.
Anyway that's only a base point. If the bike can't idle with the screws so closed, try openup 'em more. Try to keep the motor un-balanced with the front cylinder stronger than the rear.
7) set the ECU trimpots both to zero position at 12 o'clock (the one near the ECU connectors is for the rear cylinder). Try to run the pots around that position, if you have to go far away on the rich or on the lean side maybe there's a problem elsewere."
Thanks bro will try those settings and see how it goes cheers[emoji4]
 
The A63 is the standard EPROM in bikes from 1998-2000 - the small valve engined ones. The 'KAT' part is supposedly in reference to 'katalyser' which I can only guess was fitted to bikes for certain parts of the world due to emission legislation.

The bad news is that the trim pots are not enabled on a bike with an A63 EPROM. You could fit an RP58 chip from a 2001 onwards bike as they enable the trim pots. Or go for a Forza, Gabro or Doctor Rossi aftermarket chip.
 
The A63 is the standard EPROM in bikes from 1998-2000 - the small valve engined ones. The 'KAT' part is supposedly in reference to 'katalyser' which I can only guess was fitted to bikes for certain parts of the world due to emission legislation.

The bad news is that the trim pots are not enabled on a bike with an A63 EPROM. You could fit an RP58 chip from a 2001 onwards bike as they enable the trim pots. Or go for a Forza, Gabro or Doctor Rossi aftermarket chip.
Cool thanks man for the info.
 
Have jst checked spark plugs found
Front cylinder running rich. Plugs are black. Rear cylinder looks normal. Any idea wat I need to adjust
 
Have jst checked spark plugs found
Front cylinder running rich. Plugs are black. Rear cylinder looks normal. Any idea wat I need to adjust

ideally you neeed the co levels and tb throttles balanced get it done by someone who knows what they are doing and has experience of the rotax lump
 
Yep as if you were sitting on it

As you look at them looking back from the front of the bike the rear cylinder is the trim pot nearest the ecu connectors.

Keep the engine temp below 93 degrees as the ecu richens the mixture to aid cooling at that temp and it will mess up the reading. I feed a fan into the rad and stop adjusting if the rad fans kick in.
To lean out the mix on the front which way do I turn dial. Clockwise or anticlockwise
 

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