Bimmer - O2 based PC2 maps yet?

[OB_Tom Mitchell]

Hi Bimmer,

A while back you said that you were going to be developing some PC2 maps once you installed an O2 sensor in your header pipes. Have you been able to do that yet? I've got a Two Brothers slip-on and no other mods and will be trying your suggestion of using the Stage 1 map with the lean datapoints nulled out above 7,000 RPM as you suggested.

Thanks!

 

[OB_bimmerbusa]

naaa. I recently got sidetracked..... Three of us went for a long ride... stopped to rest in a beach parking lot... I parked, another busa parked next to me. 10 seconds later the third busa came flying over an embankment and took out both of us parked. Its a plastic mess now and my radiator is bent........... aaaaaaarrrrrrghhhhhhhh...
As soon as I change out the radiator and get some new plastic. I will be heading out to get the o2 sensor welded in the collector....

Let me know how you make out with the tweaked map......

[This message has been edited by bimmerbusa (edited 03 June 2000).]

 

[OB_bimmerbusa]

The bike accelerates so quickly that sometimes it difficult to determine how fast your actually going until you take your eyes off the road to look at the speedometer. When you pull the front wheel off the ground it makes it all the worse. In order to maintain the momentum your hand is twisting the throttle and the bike is accelerating like a rocket. Then the wheel comes down and its too late. baaaaaammmmmmmmmmm........
Word of advice to everyone... only pull the wheel when there is PLENTY of road in front of you. PERIOD..........

 

[OB_Tom Mitchell]

OUCH! This must be something unique to Busa riders. One of the lead guys at the local Suzuki/Kawi dealership is a club racer and has been on two wheels since he could walk. Yet he was showing off in the neighborhood and went screaming into his garage on his Busa and miscalculated the breaking distance. He rammed the wall, totalled his bike, and almost punched a bike-sized hole through the structure. It must be the "I can do anything with this bike" syndrome that these things seems to foster.

 

[OB_Tom Mitchell]

Bimmer,

Your revised stage 1 map is great for the Two Brothers slipon. I have no idea whether it represents optimal mixture (your 02 tests will tell for sure), but the driveability is superb. It can't hurt versus the stock mixture since it is only richening the settings; just less so than with the stage

As you may remember, I was getting great low-end response with the stage 2 (race slip on) map but seemed to be suffering a tad on power output at high throttle indications. Now, the driveability is great all-around and the top end is back. Thanks again, I really appreciate it.

Tom

 

[OB_BusaGeek]

Looks like bimmerbusa may be out for a while. I've done something like this with my last bike ('94 YZF750, removed the EXUP and got it tuned well) and was real successful. It's not that expensive and can be a lot of fun for the right people.

O2 sensor --
Get a Borg-Warner OS-126 from Pep Boys, it's a four wire 18mm mount sensor.

Get a suitable size spark plug anti foul adapter - about $2.

Cut the adapter to make a mount for the sensor.

Have the mount welded to the pipe at the point just after the headers all come together.

Drill hole and install O2 sensor.

Hook 2 wires to ground and +12V, the other two are to read O2 level.

.45 volts means not lean or rich, high means rich, low means lean. The sensor can really only tell lean or rich, it's not accurate enough to tell how much.

As for using it to make a map, that's where it gets fun. Either go buy expensive data logging equipment for your bike (then why would you be using a Pep Boys sensor?) or build one. It's not that hard. With an off the shelf Analog to Digital convertor ($10), a small circuit to get rpm ($5), and a Basic Stamp computer chip ($40), a simple data logger that will log an on-road dyno run can be made.

Push a button, peg the throttle, download the data, change the map. Rinse and repeat.

If anyone wants details, please ask, I'll be glad to provide them (or maybe even partial assemblies).


BTW - this post explains the handle - BusaGeek