I put a small circuit together to get rid of the EXUP error code on an R1. And it works!!! (cue post from Jimgiblett saying it doesn't work any more. . . . )
Anyway it's just 3 resistors, a transistor a capacitor and a zener - very easy to make,(much simpler than alternative circuits I've seen on the web)
Any small signal npn transistor will do - BC847 if you have to go to maplins for one... the zener's 5.1V and the capacitor is 1uF
cheers
Bob
http://www.locostbuilders.co.uk/photos.php?action=showphoto&photo=exup.jpg

I'm not using the R1 clocks so are there any other reasons not to remove the exup valve? I still have it plugged in hanging in the engine bay, I'd take it out but am not sure if doing so will affect anything else - does the ecu know if its there or not?

Cheers

Paul

I was under the impression that if its plugged in its happy

whats the price of making one of these jobbies?

Im planning on just mounting my exup valve under the dash.

Paul G,

There is no reason why you cannot remove the EXUP valve, it has no effect on the running of the ECU etc.

The error code on the R1 clocks is the only downside (and that can be eradicated when the engine is running by shorting the EXUP wires together). BoB C's circuit additionally stops the error code when the ignition is on but the engine is not running. Nice to see someone come up with an economical solution to that.

Cheers

Paul

Nice one fellas, thats another kilo saved!

Cost? these are all 2p components + a couple of cm of veroboard. If you know anybody who's into electronics they'd knock it up in no time.
A soldering iron is probably not a bad investment for a car builder anyway for splicing looms & such, all the bits are at maplins & similar stores.
cheers
Bob

The EXUP servo connects only to the ECU. The ECU must send an error message to the clocks. I doubt that the ECU would stop the bike running jsut because the EXUP is broken but I guess there may be a possibility of it limiting something - a kind of limp home mode. I've never heard of such a thing though.
The circuit shown below can be yours for less than £1, plus a small box if you want to do it right. Sounds like a bargain to me. As an electronics engineer, I might have tried that before riveting my EXUP servo to my engine cradle.

Just to clarify that there absolutely is NOT any kind of limp home mode or reduced performance map from the R1 ECU if the EXUP is not there.

Race teams junk the EXUP and they would not do this if it had any adverse effect on engine performance. Also all the best aftermarket exhaust systems for the R1 junk the EXUP too. You can happily resign it to the scrap bin :-)

Cheers

Paul

Just to say its all working fine.

The method of display of the diagnoistic codes on the 98-01 clocks is different to that on my 03 inj R1. Where as you get the Tacho tango on the carbed engine you get proper numeric diagnostic codes on the inj model. More significantly though, where as with the carbed model clocks the error code was only present when the ignition was on but the engine not running. The inj 03 clocks continue to give a diagnostic error while the engine is running which is more than a little annoying. So a big thanks from Bob for fixing this with his circuit.

ps. As Paul says no limp home mode and if you are not running the bike clocks probably of no consequence.

[Edited on 7/1/06 by jimgiblett]

I cannot get rid of the exup error on my 98 R1. I tried plugging the motor in, a vtac circuit, shorting etc as recommended on the web but non of them make it go away. I have had to connect my tacho directly to the ignition coils.

Also, can't get my acumen gear indicator working above 2000rpm, as soon as i rev it loses the signal!

Any ideas please??!!

R1minimagic, are you connecting both plugs to your EXUP motor? I believe that one of them connects via a bullet connector. IF that is OK, bell out the wires from the ECU plug to the EXUP plug. Check that your loom is OK. After that, try borrowing an EXUP servo off someone to see if that is the problem, otherwise it might be your ECU.

r1 mini,are you sure its not a fuel sender signal

I have been using the car like this for the last 2 years with no problems apart from not being able to get the gear indicator working above 2000rpm. It programs the gears ok but loses the signal when i rev. I wanted to try using the ecu tacho output for the gear indicator but i cant bcos of the exup error. After trying everything (with no success) i decided to cut all the wires out of the loom that i didnt need, including the fuel sender.

What would no fuel sender manifest itself as??

Cheers

No fuel sender is another tacho code (can't remember which without looking in my manual). I got rid of this by linking out the wires with a 10k resistor (the only value I had kicking around at the time!). It works a treat....

I've never done any electronics before but this exup circuit looks worth a try. I did a bit of reading on simple circuits and fitting the components correctly so now I've drawn the components as if I were fitting them onto stripboard. Can anyone tell me if I'm going about this the right way or have I completely screwed it up?

Also is the BC547 transistor OK as I can't find a BC847 on Maplins.

Cheers Steve.
Rescued attachment IMG_1428.JPG

Yo 'highspeeddirt'
good try - the BC547 will be fine.
tip - use a -4mm drill to do the track cuts (just spin it in your fingers)- it makes a hole useless but the hole guides the drill to cut the track nicely. - heres a pic of something else
http://www.locostbuilders.co.uk/photos.php?action=showphoto&photo=Dsc00532.jpg
put the transistor on to 3 strips in line.
Shame I didn't photograph my prototype from the other side! I'll try to come up with a picture like yours tonight & post it on here.
cheers
Bob

[Edited on 13/1/06 by Bob C]

Cheers Bob. I've had another go and this time I've added the anode, cathode and BCE for the transistor. Is this any nearer?

Steve
Rescued attachment IMG_1429.JPG

Only 1 fault I can see - the resistor in the transistor collector is shorted to itself. Loop the resistor leg over the other side of the collector & you'll have room to make the cut.
cheers
Bob

Like this?
Rescued attachment IMG_1430.JPG

I guess I also need to put the IN4148 two holes apart and cut under it as well.

Steve

Hah - good point.!
Good luck with it!
Bob

I've just noticed the wiring on my 03 exup differs from the earlier models. There is no black/yellow. Instead there are two black/blues. I assume from Jim Giblett's post that it works on an 03 motor so what has to connect where?

Also a final question, where does the positive leg on the capacitor connect? I think it's the bottom row but want to be sure.

Thanks Steve.

[Edited on 13/1/06 by highspeeddirt]

+ side of polarised caps (and LEDs) is always the longer lead. The neg side connects to the transistor emitter.
as to the wiring - the exup has connections to both plugs on the ignition module (carbed models) one has exup motor connections (bla/red and bla/yel) and the other has the feedback pot connections (bla/blu and whi/red)
Hope that helps you work it out!
cheers
Bob
PS - what I call bla/yel; jim called it bla/green so there may be a colour change.... I suspect one of your bla/blu is what jim called bla/green.

[Edited on 14/1/06 by Bob C]

Thanks again Bob.

You're right one of my black/blues is in fact black/green. So that makes more sense. The components arrived this morning so now I'll see how good my soldering is!

Cheers Steve

Steve - another thread reminded me of this - did you get it working?
Bob

How about this one? I think I'll try it at the week end.

What have people done for conenctors into the main loom?
Rescued attachment exup.GIF

Looks really neat smart51.
You could solder direct to the loom or put a 4way connector pair in for easy removal in case of failure - your choice.
One thing I've done in the past with small circuits like this is to 'pot' them by covering all over in hot melt glue. Easy to do but to all practical purposes irreversible - so do it AFTER you've got it working! Trouble with vero is that the copper strips corrode in an engine bay & after a few years the circuit would stop working otherwise. This circuit is so small and light it can be just taped to the loom if it's 'potted' as described.
Bob
PS points to watch - you've used a tantalum cap - be SURE it's polarised correctly or it'll go pop. Also - is that a 2N222? whatever the can is probably electrically connected to the transistor collector so watch it for shorting to things (eg resistor leads, or the car chassis) on the top side of the circuit

[Edited on 9/2/06 by Bob C]

I have got a potting box ready for the circuit once it is tested. I'd rather connect to the existing plug than cut it off and wire in diectly. I'll have to give it some thought.

sure if you have plug, socket & bike loom that's the way to go.
Bob

I tried the circuit and it works upto 10,000 RPM during acceleration and upto 7500 RPM steady speed. Above this I get the rev needle error code thing. The circuit is correct, with correct value components and no mis-soldering.

Has anyone got this circuit to work properly?

Also, the zenner diode gets quite hot and I've used a 1.3W diode as maplin ran out of 0.5W ones.

I've only had the chance to test mine on startup and idle with a few blips on the throttle. Mines an FI motor so I dont get the tacho tango just the error codes.

When you say the zender gets hot is this a fire risk as I have mine tucked away where it isnt easily accessible?

Rgds

Jim

[Edited on 14/2/06 by jimgiblett]

The zenner gets hot to the touch and the plastic box it is in gets quite warm. I did 10 - 15 miles to try it out and there was no fire.

Hmmm - interesting. Are you sure you used 47kilo-ohm resistors smart51 - if you did it shouldn't be possible to put enough watts into the zener to warm it:
12V on bl/red to 5V on the zener through 47kohm is about 150micro-amps and the zeners are specced at 5milliamps.
Check for for shorts with a meter - you can get whisker small filaments of copper left when you do a veroboard like this.
If the circuit's right & the zener's getting hot it means the circuit in the CDI unit must be using the pot's resistance, which would be a bit of an arse to say the least. Jim, you're gonna have to take another look at yours I think! It'll be at least a month before mine's going & I don't have a silencer yet so I might not be very popular doing 10krevs tests...!!!!
Cheers
Bob
PS - Ta for the heads up Jim!

Smart - looking at your resistors I get blue red orange brown which could be 52k or something else (I always check with a ohmmeter to be sure) - can you measure the resistance of the top resistor?
cheers
BOb

Yeah. I got the resistors out of a resistor book. the numbers are printed below the pack of resistors. I am allways using the wrong ones. I have since replaced them with 47K. I have done a full multimeter check on all the components and from each track to each adjacent track. No shorts.

Max power in the Zenner should be 430 uW at an alternator voltage of 13.8V. Not enough to get warm. Perhaps I should take it out and have another look.

I have measured my circuit and it is all OK. I measured various voltages with the ignition on and found some strange results. The motor input to the plain diode was switching on and off rapidly, enough to give a 7.5V AC and 3.5V DC reading. The other motor input was hovering around 0.7V, enough to leak current out of the cap. I guess that the cap voltage is not holding steady enough and the ECU is trying to maintain EXUP position by nudjing the motor forwards all the time. This behaviour is not seen when connected to a proper EXUP servo.

Has anyone got this circuit to work properly?

OK if the 2nd motor output is hoveriing round 0.7V that's enough to turn on the transistor - solution would be to include a forward biased diode in the transistor base circuit - do you want to try that smart51?
I'm surprised at the 0.7V thing. The circuit was designed assuming a very simple motor drive/ position control system. I wonder if they've used an audio power amp chip to drive the motor - that would explain it! & it wouldn't be a bad idea either - integrated driver with short circuit protection costing peanuts.
cheers
Bob

I am still wiring the car at the moment so I've not yet built/tried the circuit. It will be a pity if it doesn't work as that exup motor seems heavier every time I look at it.

Steve

I fitted a zenner into the base of the transistor, as well as the resistor. Both motor inputs bounce up and down. It's as if the circuit reacts to fast and the ECU is saying up a bit, oops too far, down a bit, oh, too far, up a bit...

I'm tempted to give it up as a bad job. The EXUP isn't that heavy campared to a whole car.

Has someone got a bette circuit?

Thats a reasonably accurate description of how negative feedback in servos works......
With the extra 'turn on' voltage on the transistor do you still get the error code at high revs? Is the zener still getting hot?
If the circuit is reacting too fast for the controller, increasing the size of the capacitor will fix that.
There's another circuit on biketransplantcentral (search google for that) which uses a digital potentiometer chip + timer + some logic.
- which is why I thought a much simpler circuit would do the job & made one which Jim tried & it fixed it for him (!).
Shame it's not worked so well for you yet smart51 - It would be nice if you could persevere for the sake of getting a good solution for the R1 engined community, but I can understand if you don't want to spend too much time on something relatively new & untried.
All the best
Bob

My diagnostic codes have certainly gone at start up and a few blips of the throttle all seems fine. But I am yet to give it a good thrashing like Smart51 has. So watch this space.

- Jim

I replaced the 1uF cap with 4.7, 10, 47 and 100uF before the "bouncing" came down to a reasonable level. It works at all engine speeds and road speeds now, with over 100 miles of testing today. The zenner doesn't even get hot. the only problem is that the tacho needle bouncing now happens with the ignition on but the engine off. I didn't check the tacho needle with the other values. I might experiment further another day.

If you have a bouncing tacho when the ignition is on but the engine not running you are in the same position as if you had just spliced the exup wires together. That was the set up I had on my old 2000 R1.

Cheers

- Jim

The ignition module continually correcting the capacitor voltage is really not a problem - like I said - that's how servos work! I don't know what the exup servo system reacts like, but if the CDI module is expecting it to reach its setpoint in 1/2s or so - a 100uf charged thru 47k is going to take 10 times that, so that would explain the "tacho tango" on startup - the circuit is behaving like a really slow EXUP servo & the CDI thinks it's goosed when it does its power up tests. So I'd back off on the microfarads until the powerup selftests pass.
cheers
Bob
PS shame this ain't the best way to debug circuits... it's so much easier 'hands on' . To be honest I was rather surprised when Jim said it worked 'out of the box' - I expected this kind of 'honing' to be required!

Which wires do you splice together to stop the tacho bounce when the engine is running? It might give me an idea how to fix the circuit.

IIRC thr black / Red and the White / Red on the 5XV motor. Never had any "tacho tango" other than on ignition and engine not running.

- Jim

Here's an old old link from the early days of BECs....

http://biketransplant.tripod.com/exup_replacement.htm

[Edited on 19/2/06 by stevebubs]

10 uF cap fitted and tested. No problems with the engine off or on at any engine speed and any road speed. Next I'll try it without the extra zenner in the base of the transistor. At last.

Weyhey - at last - I'd leave the extra diode in, it's not doing any harm.
I'll edit the circuit diagram in the 1st post to include your findings. I'll just put another 1n4148 forward biased in the transistor base & change the C to 10mikes
cheers
Bob
PS OK I'll edit it later when I'm at home....

[Edited on 21/2/06 by Bob C]

I've deleted the post with the original schematic & here's an update with Smart's mods. I've swapped his zener for a normal 1n4148 considering the voltage appearing on that input.
Bob C
Rescued attachment exup.GIF

I built a nice new circuit up after all the modifications to the first one. Tested it yesterday and it was fine. Took it off and potted it in epoxy. Went out today and the tacho was bouncing by the time I'd got to the end of the street. Lucky I'd built two then. It seemed worth while for the cost of a few penny components.

What' the best way of weatherproofing my new circuit then?

Try hot melt glue on it if it doesn't heat up too much and remelt it.

EDIT: (vero layout) Smart51's layout is fine just need to crank the cap value to 10 mike - sorted. Going to knock one of these up tonight...

[Edited on 29/8/07 by hobbsy]

Apologies for resurrecting an old thread but after building this circuit over a year ago I finally got around to fitting it a couple of days ago.

However there isn't a black and yellow wire on my 5PW EXUP connector, nearest is black and green. Also there's a blue and something wire but I'm guessing that one is left unconnected.

I tried connecting the black and green wire to where the black and yellow goes on the schematic and I still get error code 17

What colour wires have other people connected on the 5PW as I'm guessing its different to the 4XV but from what JimG put the same circuit works - just need to know which wires...

[Edited on 19/4/09 by hobbsy]