I've started this thread for two reasons - one to share my install process, and two, to get help

I recently purcased an XT GPX Pro lap timer ( http://www.xtracing.com/en/gpxpro/index.php ). The colored wires that I refer to here are NOT wiring harness but one of the 6 wires on each of the A and B data acquisition cables from the timer.

I'm just in the process of wiring up my 2005 CBR 600 RR race bike. A lot of the harness has been "pared down" so it's taken some creativity to rebuild missing parts - the horn isn't on the bike so I stole that for 12v power (A-red) and I got ground from the battery (A & B black).

I re-ran power (OEM white green) to the front brake switch. Then I ran a yellow wire from the other side of the switch back to A-Yellow. I configured this data input as a switch (and named it brake). This gives me the instant that I went for the brakes. (I can look at the accelerometer data for brake hardness).

To get RPM I tapped into the non-common wire above the coil on #4 - and ran that to A-Green. This is where I seem to be having problems. I believe A-green is digital input 5. Maybe that's the problem? I went into the data-aqu. setup, set #5 as RPM, and enabled it at 100 Hz. I turn the key on and the GPX powers up. I start the bike and no RPM is reported.

Tomorrow I'll be looking for the throttle position sensor --- not sure which wire I'll need to tap for that --- if anyone knows I'd be greatly appreciative.

Pictures to follow of the install - and any notes that I've taken that seem helpful to other RR owners.


For this install I plan on logging:
1) RPM
2) Brake (on/off)
3) Throttle Position
4) Temperature
5) ???

The unit without adding anything gets speed, acceleration, lap times etc.

With RPM it also provides shift lights and a gear indicator.

Thanks all!

 

My thread over on the XT website:
http://www.xtracing.com/forums/viewt...105&p=550#p550

And a cross post here:

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The first thing I have to say is that lap timer looks awesome. A lot of people have

been stopping to see mine, and I've been glad to chat about it. So far, only myself

and the local distributor have one at the track -- however the interest is there and I

think the numbers will speak for themselves.

One general comment. My personal preference is to always cut and solder wires. I feel

very comfortable with the soldering iron --- the provided vampire style taps will work

just fine. If you do go with the soldering route buy a length of heat shrink the right

size and use it liberally. It will provide both mechanical and electrical insulation

FAR superior to electrical tape. On a race bike that matters even more than your

commuter.

My second general comment; when you tap into a wire always consider what side of the

plug you tap into. For example - if you tap into the accessory side of the plug, to

remove the accessory means you need to remove the timer, where if you had of installed

on the bike side of the plug you only need to disconnect the OEM plug to remove the

part. Say the throttle position sensor packs up -- you'd only need to pop it out of

the harness and replace -- no playing with the data acquisition wires.

My third comment is from a marketing perspective -- a lot of bike forums have a 4

letter word search minimum -- 3 letter words are expensive from a search and database

perspective. When searching for "XP GPX PRO" it becomes challenging -- quite often

nothing is found on first pass, but if you search for laptimer you can sift through

and sometimes find something... just a comment on web visibility.

So the first part is easy - drop the plastics from the bike. Figure out where you want

the A/B data acquisition wires to go (somewhere you can unplug them easily enough, but

don't interfere with the steering. The second consideration was -- will I keep the

existing dash (mostly broken -- fuel/temp, neutral, and oil pressure work) or remove

it and wire the important sensors to the GPX? I decided to keep the stock dash and

cover up the tach - speedometer portions as they were broken anyhow.



The next thing to do was to find power. As this is a race only bike quite a few wires

have been cut and removed. I was lucky and found the old horn power source. I tapped

this power source with the RED wire from cable A (see below). A note about this choice

- the horn wire is ONLY alive when the bike ignition is on. Once this is wired in you

can turn the key on and the system turns on. Set the auto-time off at something

reasonable and it shuts down on its own. I have set mine to 20 minutes as the

batteries last quite well and I never want it to turn off if there is a stoppage on

the track -- I missed a session because of that once.

I also needed a ground. As I wanted the timer to be stand alone from everything else,

I ran the back wire back to the battery. The Black wire ties into BOTH the A/B black

wires. (See below, very hard to see but it runs along the same side of the bike down

to the battery).

Once that was done it was time to start the data acquisition. In the image below you

will see the bright blue wire from cable A. On the left side of the honda is the

throttle position sensor. I pulled the sheathing back and soldered/heat shrunk on the

blue wire.

(Looking at the left-front side of the bike)


The next one to find was RPM. As the CBR has coils over the plugs you can't do

inductive pickup on the coil wire. What I did -- and it works beautifully -- was the

suggested method of taping into one of the NON-COMMON wires going to one of the coils.

As I like the right side I picked #4. I looked at each coil and noticed that each one

had a black-with-white-stripe wire in common. I LEFT THAT ONE ALONE and took the other

one on #4. In the picture below you will see the green wire -- that wire runs from the

coil to the Green wire on cable A.

All of my brake light switch wires were cut off. In order to get the initial

millisecond I touched the front brake I needed to run power to the brake switch and

back to the data acquisition system. I found the original brake light power source in

the harness on the right hand side. I threaded it through the OEM sheath up to the

brake switch. With my crimper I installed a female spade terminal and pinched it with

the pliers. I forced that onto the post of the brake light switch. I then ran a YELLOW

wire from the other brake light switch post back through the sheath to the other

acquisition wires, all the way up to the the yellow wire on cable B.

The other point to observe in this photo - you can see the plugs for the data

acquisition wires. They were originally tagged with a paper A and a paper B. I don't

think that will last very long so I wrapped each of the B ends with white electrical

tape - this way I always plug them in properly. Also note that where I have located

them gets covered up by the tank plastics, but I can still reach in and unplug/connect

them without removing the plastics.



The final thing to do was to setup the dash to look the way I wanted... all I really

wanted track side was RPM - but for fun I included speed, brake (on/off), and gear. I

set the shift light points which is about the only thing I notice on the track -- I

never look down as I ride 99% by feel/sound and not by visual cue. I highly suspect

that's common. Here's the dash layout I have currently -- but it is so easy to modify

I might play with it some more yet! (Also note that when you are in the pit you can

scroll through all the data (Sessions AND individual laps) to see which

session/lap/split you were doing well. Sometimes I'll run 5 laps working on a

particular corner. Come in and see which if the 5 approaches worked the best. Run

another 5 laps on the same corner working on the improved line -- and see what

happens. Then I'll run a few full track sessions and see if I was able to put the

parts together.



I have done a partial test of the system on the May 8th racer test day -- at that time

I had only got the RPM's partially working (grabbed the wrong wire the first time!)

and it was really only giving me speed, intermittent RPM, and throttle position. From

only the speed, some RPM data, and the throttle position I have already learned a lot

and can not wait to get back to the track to apply what I have learned.

I was also really impressed by how easy it was to set split time points on the map --

right in pit lane! I just went to the setup menu, selected the track, and added a

series of split points - it recalculated all of my laps to data and I was back out on

the track working on the next series of corners -- during my rest times I got to check

in and see if I was making the right changes or not.

One of the most important data channels for me was throttle position -- it will

surprise you to see how little throttle you actually use -- the hero factor on the

back straight when all the world is shaking around is surprisingly low. A huge lesson

was simply replaying the data back on the computer and watching what my right hand

ACTUALLY did as opposed to told me it did.

Here is a screen cap of how I have my GPStudio setup -- I've got speed, throttle

position, rpm and brake position on the right side. My laps down the left side. On the

top I've just got one lap shown here - but you can put several laps up to compare them

side by side. The track shape was drawn completely by the unit -- no downloading maps

or anything silly like that -- it's fantastic!


I will also be retaking the race school to get more time on the track and get more

feedback on my riding style -- missed round one and the bike was very sad -- round 2

is coming up and she's much happier.

A very sad bike missing her very precious forks


A very happy bike being tested by "iknowaguyvinyl" owner/operator.


Till next time -- keep the rubber side down and enjoy your lap timer!



What's next? Setup the accelerometer and gear indicator parts of the timer - then run

laps until the unit is full; repeat.


THANKS GUYS - love the product and learning a lot.
Woot.

 

I tapped most everything into the ECU. (I looked at your schematic, think it is the same but I didn't study it).

Cable A - Black, to ground. Red, power (I used taillight). Green - RPM. Connect to Black ECU connector, pins 11, 12, 13, or 14. Blue is NOT used. Inductive won't work. Brown to gray ECU pin 14 (throttle position) and Yellow to Gray ECU pin 27 (water temp).

Cable B - Black to ground, Red to the brake switch (giving it power), blue to other side of brake switch for BRAKE. Green not connected to anything yet.