HOW TO - DIY exup motor eliminator

[sss r1]

this thread is for those that removed the exup valve from their bike (for whatever reason) and ,are stuck with the exup motor connected to the wiring harness and doing nothing .
the exup motor weights a bit more then 300gr , disconnecting the motor will cause error codes on the speedo cluster .

it took me some time to test various circuits ,and find the easiest way to eliminate the EXUP errors , so basically ,anyone can make it.

for those that dont know this allready , there are commercial units available , but they cost "a bit" more then the circuits described here

as far as i know , the EXUP works the same way for all yamaha bikes (all R1s , WR ,VMAX etc...) so the same tricks described here ,can be used on all yamaha bikes.
the only difference is the color of the wires connected , in this thread i will only discuss 98-08 R1s (the 09 R1 got no exup) ..

[sss r1]

the basic principle of operation (u dont have to read all this )

as can bee seen in the pic , there are 5 wires connected to the servo .
2 wires are powering the small electric motor .
each of those wires can be 0V or 10V (approx)
this makes it possible for the motor to turn in both directions , for example :
if mp1 (motor power 1 in pic) is at 10V , and mp2 is at 0V , the motor turns clockwise .
if mp1 is at 0V ,and mp2 is at 10V the motor turns counterclockwise .
so the motor opens the exup butterfly when turning in one direction , and closes it when it turns the other way.

yamaha added feedback to the motor , in case it gets jammed .
the feedback is a basic potentiometer , connected to the motor shaft (via gears) .
there are 3 wires which are connected to the pot , two of them supply the power (+5V and gnd in pic) and one is the feedback wire (output in pic) .
the 2 power wires are also supply power for the TPS sensor , speed sensor and some other sensors (so dont short them).

as the motor turns , the voltage on the potentiometer output wire changes , it goes from 0V to 5V when motor spins in one direction .and goes from 5V to 0V when it spins the other direction .
the ecu decides where to stop the motor .it depends on engine rpm , tps and speed you are going (it can stop the butterfly half way open , this happens when the feedback is approx 2.5V)
if the ecu is trying to spin the motor , and , for some reason the feedback does not change , u will recieve exup error.

[sss r1]

the resistor method :

i read around here that some guys could get away with just using a single resistor . the resistor should be attached between one of the motor power wires , and the output wire .

there are few prombles with this method . as i wrote in previous post , the motor power wires get signals of 0 or 10 volts from the ecu , while the output feedback wire should get a signal of 0 to 5V .
attaching a single resistor from the motor power wires to the output wire , will drive the output to +10V , when 5v is the maximum it should get.
i dont know what types of protection the ecu has , so i didnt even try this method .

[sss r1]

the upgraded resistor method :

in this method , the output wire will be safe from getting more then 5V .

this circuit will pass the initial ecu tests on most R1s , but , as u will start riding , u will still see the exup error light or the dancing tach needle from time to time.

this circuit is for those that want fast and easy solution.

[jhelmuth]

I imagine that the exup motor is servo control type. So wouldn't a resistance ladder circuit work as a "simulator" replacement?

[Dark_]

Why hasn't anyone just opened up one of the 'Servo Eliminator' plugs that you can buy over the counter? I bet they are simple to copy.

[sss r1]

in my drawing i used different names for the wires (motors power , out , gnd etc...) this is because on a different year R1s , the colors are slightly different , the next table will help u to find the right wires .

note : the wires in the table are for the bikes wiring harness ,and not the small harness which is connected to the exup motor.

[sss r1]

the next circuit is more complicated ,but it works just fine . no error codes or dancing needle.

as u can see , it uses 5 components , which makes it a bit hard to assemble without any PCB (printed circuit board) , but its duable.
the parts dont cost much (less then 10$ ) and u can find all of them in your local electronic shop (or order from digkey , farnell , ebay etc...)

[sss r1]

Originally Posted by Dark_

Why hasn't anyone just opened up one of the 'Servo Eliminator' plugs that you can buy over the counter? I bet they are simple to copy.

commercial units use digital potentiometer circuits.
they cost more , and also need to be assembled on a PCB (so the average joe wont able to assemble).
making a single pcb can cost u as much as 100$ , i dont know how much it would cost in the states , but my guess is that it will still be too much .

i'm still testing the last circuit i posted , if i find any problems with it , i see no other way but using the digital potentioeter methods , so i will publish the circuits for it also.
a will describe the assembly of the last circuit tomorrow .

[Baedarlboo]

This has been floating around for a while....

[sss r1]

Originally Posted by Baedarlboo

This has been floating around for a while....

this circuit is no better then the single resistor method (but its got protection from sending high voltage to the output).but still , it will work same way as the first circuit i posted.
without a capacitor , this circuit got only 2 position - exup fully closed or fully open (and it uses way too much parts for that).
with that circit (or the first one i posted) the ecu will pass the inintial tests , but once u start riding and cruise for a few seconds around 6-7 krpm (where the exup opens partially) t will show an error code.
the second circuit i posted will work much better with less parts ,because it can show middle positions (or any position the ecu requests) also .

[Carnag3]

I spent $60 and bought the Graves plug and called it a day.

[novasquid]

how about something like this? from here: http://www.paylessforglasses.com/blo....php?itemid=30

[CroR1]

so resistor mod is not safe in your opinion?

[CroR1]

will this mode work for an R1 as well?

Originally Posted by novasquid

how about something like this? from here: http://www.paylessforglasses.com/blo....php?itemid=30

[MotoGPracing]

Originally Posted by CroR1

will this mode work for an R1 as well?

Look at post 7 & 10, those color codes dont match R1. I dont really see what there trying to get across with the resistor @ the connector? Hooking it up to 2 wires???

[B'eater]

It cost me less than a penny to fix the check engine light issue.

[CroR1]

anyone has a real pic of how to wire this and how it looks like? i dont dig these diagrams.

[mattf]

There's another alternative to fixing your dancing tach, and its as simple as picking up someone's old servo motor in the "parts for sale section." Thing to watch out for is the 98-01's servo motors themselves are the same as the later 02-03's, yet not a direct plug-n-play. They will however, work just as well if you can solder up a couple of connectors.

Thanks to sss R1 for his diagram in post 7, because that saved me a TON of time when I realized that an 02 servo motor wouldn't plug right into my 01 track bike.

The 98-01 servo motors have five wires coming out of them that plug into the harness....4 wires leave the servo motor housing and end in a 4 pin plug, with the fifth one on its own that plugs into a male/female coupler in the harness. The 02's require a 5 pin plug frombe plugged into them. When I looked I thought "damn, not going to work." I looked at the service manuals and the color codes are different, so at first I thought it wouldn't work.

I saw sss R1's diagram tho, and I figured it right out with the help of the service manual (the 02 manual, you just need to see which color wires end up where in the harness so yo uknow how they plug into the servo motor). So I cut the wires off of the 98-01 servo, I soldered some small female spade connectors onto the ends, and plugged them into the appropriate spots on the 02 servo motor. Plugged the factory end back into the harness, fired up the bike and voila! No more tach tango!

Easier than cooking up a homemade servo sub, cheaper than an aftermarket alternative. Thanks again to sss R1 for posting up, huge help!

[Ryans79]

what's the value of the Diode D1 ?