BoosterPlug -R1150RT

http://forums.bmwmoa.org/showthread.php?t=47355

CO Pot Value Discussion

Yup, that was me with the 9 turn 1K Pot. I think I decided on 1K from info gained on ADVrider forum. It worked OK. Only reason for a 9 turn was the radio shack was out of the one turn. I installed the pot in the fuse/relay box with a dab of GE clear silicon. Need to disconnect O2 sensor to force continuous open loop fueling. Don't know if it is really necessary to either cut the jumper or remove the yellow/gold ccp but I did cut the jumper for the halibut.

Red100RT said:

Yup, that was me with the 9 turn 1K Pot. I think I decided on 1K from info gained on ADVrider forum. It worked OK. Only reason for a 9 turn was the radio shack was out of the one turn. I installed the pot in the fuse/relay box with a dab of GE clear silicon. Need to disconnect O2 sensor to force continuous open loop fueling. Don't know if it is really necessary to either cut the jumper or remove the yellow/gold ccp but I did cut the jumper for the halibut.

Click to expand...

Looking at the schematics Pin 2 of the connector is the wiper and interesting to note the air temp sensor, oil temp sensor and CO trimpot are all ground referenced to the same pin (14) of the Motronic 2.2 ECU. Also, the reference voltage for the TPS and CO Pot comes from the same pin on the Motronic. I think it's likely there is a comparator circuit in the ECU using these two inputs in tandem since they share the same VRef and GND points. Hmmmm. Just gets curiouser and curiouser.

Dang I wish we could find some documentation on the Motronic ECU units! I hate black boxes.... Even a flowchart would be nice eh?

I'd like to be positive it's a 1K trimpot but there is no info on the schematic or parts list as usual... Maybe one of our club members has a CDN 95 or 96 model and can just pull the plug out to measure the resistance from pin 1 to pin 3 of the pot connector.

It is not uncommon for circuits of this type to share the same Vref and ground. I don't see any reason to conclude that it uses them in tandem from the fact that they run from the same V+ and Gnd, they do it this way to provide noise free paths for the sensistive sensors. Each of those inputs goes to its own comparator, I have seen the schematic.

Having looked at the schematic, the inputs all go to an ASIC (for which there is no public documentation).

The O2 circuit is even more interesting than the others. Because the sensor cell in the O2 sensor is isolated from the case, they are able to float the low side of the cell to 140mV, meaning that the plus side of the cell is biased to 590mV. An internal comparator measures the difference as 450mV, as reported by the GS-911. By biasing the ground up 140mV the "dumb" Motronic can tell if either side of the sensor cell is damaged, disconnected or grounded. It just can't tell the most important thing--if it is old and slow, leading to wider swings in AFR!

RB

Roger 04 RT said:

It is not uncommon for circuits of this type to share the same Vref and ground. I don't see any reason to conclude that it uses them in tandem from the fact that they run from the same V+ and Gnd, they do it this way to provide noise free paths for the sensistive sensors. Each of those inputs goes to its own comparator, I have seen the schematic.

Having looked at the schematic, the inputs all go to an ASIC (for which there is no public documentation).

The O2 circuit is even more interesting than the others. Because the sensor cell in the O2 sensor is isolated from the case, they are able to float the low side of the cell to 140mV, meaning that the plus side of the cell is biased to 590mV. An internal comparator measures the difference as 450mV, as reported by the GS-911. By biasing the ground up 140mV the "dumb" Motronic can tell if either side of the sensor cell is damaged, disconnected or grounded. It just can't tell the most important thing--if it is old and slow, leading to wider swings in AFR!

RB

Click to expand...

Well, I guess they deserve kudos for building easy shop maintenance capability into the electronics. Mechanics love go/no go testers! Understanding how it actually works inside the black box... well there's no time for that in a modern dealership.

A fellow on the sport touring forum informs me the trimpot is indeed a 1K ten turn pot so I'll be wiring one of those up shortly.
So the plan is:
- No CCP
- No O2 sensor
- Install flow through exhaust (SuperTrapp)
- Install CO trimpot
- Install Booster Plug

Here's hoping it runs and sounds great!

Hello Wanderer,
If I were you I would do all the things you list but try it before buying a booster plug, you might like it. Why the flow through exhaust? Just curious.

Happy Wanderer said:

Well, I guess they deserve kudos for building easy shop maintenance capability into the electronics. Mechanics love go/no go testers! Understanding how it actually works inside the black box... well there's no time for that in a modern dealership.

A fellow on the sport touring forum informs me the trimpot is indeed a 1K ten turn pot so I'll be wiring one of those up shortly.
So the plan is:
- No CCP
- No O2 sensor
- Install flow through exhaust (SuperTrapp)
- Install CO trimpot
- Install Booster Plug

Here's hoping it runs and sounds great!

Click to expand...

Good, so you have triangulated on the trimpot value. With all due respect, I think you're changing too much too fast, based on what I've learned from data taking on my 2004 RT.

Here is how I would proceed if I were you, but please feel free to ignore this advice as worth what you paid for it.

1) Disconnect O2 Sensor, install BoosterPlug and drive. This will bring your cruising AFRs to 13.8:1 plus or minus.

Or if you prefer

2) Disconnect O2 Sensor, Pull CCP, Install Trim Pot, adjust for best idle. This will also bring your AFRs to 13.8 - 14.0.

Drive it in this condition for a while and see how you like it. This becomes your new baseline. (Keep in mind, once you pull the O2, the Motronic will no longer have any ability to adapt to changes in volumetric efficiency (VE, how much air it ingests in each gulp), fuel pressure, fuel injector performance, or E10. That's the bad part of pulling the O2. The good part is the Motronic won't modulate the fueling richer/leaner.)

If you are satisfied with 1) or 2) then put on the exhaust (?) and see if it rides the same. If the VE changes due to the new exhaust (I don't have a clue if it will), you may find the mixture leaner (likely) or richer. From there you could decide what to do about 1) and 2) above.

Red100RT said:

Hello Wanderer,
If I were you I would do all the things you list but try it before buying a booster plug, you might like it. Why the flow through exhaust? Just curious.

Click to expand...

I already own the Booster Plug. I had both a Techlusion R259 and the BP when I sold my 96RT. Opted to keep the BP as it was a tidier solution and did the job just as well.

The SuperTrapp pipe and exhaust came form a club member who took it off his bike when he sold it.
I am curious to see:
- what it sounds like (I suspect it sounds like the Remus but you can tune it with discs)
- what difference (if any) it makes to performance

It gets rid of the catalytic, the O2 sensor and sheds quite a few pounds in the process. This setup is _very_ light.

Oh yeah.. and it looks cool!

Happy Wanderer said:

I already own the Booster Plug. I had both a Techlusion R259 and the BP when I sold my 96RT. Opted to keep the BP as it was a tidier solution and did the job just as well.

The SuperTrapp pipe and exhaust came form a club member who took it off his bike when he sold it.
I am curious to see:
- what it sounds like (I suspect it sounds like the Remus but you can tune it with discs)
- what difference (if any) it makes to performance

It gets rid of the catalytic, the O2 sensor and sheds quite a few pounds in the process. This setup is _very_ light.

Oh yeah.. and it looks cool!

Click to expand...

If you pull the CCP, O2 and put in a CO pot, trim for idle and then add the BP, you will most likely drop the cruise AFR to 12.9:1. Seems like a big step.

Roger 04 RT said:

Good, so you have triangulated on the trimpot value. With all due respect, I think you're changing too much too fast, based on what I've learned from data taking on my 2004 RT.

Here is how I would proceed if I were you, but please feel free to ignore this advice as worth what you paid for it.

1) Disconnect O2 Sensor, install BoosterPlug and drive. This will bring your cruising AFRs to 13.8:1 plus or minus.

Or if you prefer

2) Disconnect O2 Sensor, Pull CCP, Install Trim Pot, adjust for best idle. This will also bring your AFRs to 13.8 - 14.0.

Drive it in this condition for a while and see how you like it. This becomes your new baseline. (Keep in mind, once you pull the O2, the Motronic will no longer have any ability to adapt to changes in volumetric efficiency (VE, how much air it ingests in each gulp), fuel pressure, fuel injector performance, or E10. That's the bad part of pulling the O2. The good part is the Motronic won't modulate the fueling richer/leaner.)

If you are satisfied with 1) or 2) then put on the exhaust (?) and see if it rides the same. If the VE changes due to the new exhaust (I don't have a clue if it will), you may find the mixture leaner (likely) or richer. From there you could decide what to do about 1) and 2) above.

Click to expand...

Thanks for the advice.
Since I do not plan to install the new can until the bike is tuned and ready I could try both 1 and 2 and see what happens. I've been running it all last year with the CCP pulled, the O2 sensor still plugged in and with a booster plug. Saw some improvement but still runs quite lean according to the tan/whitish look of the plugs. Mileage is around 42MPG over all but still surges and causes difficulty trying to cruise slow at steady speeds in city traffic or very slow in parking lots etc. Hi speed highway riding is pretty OK till you have to cruise through small towns with lots of lights! Then it gets annoying...

I won't be on the road for a while yet though since the weather is spotty and I have another bike to ride on the few good days we are getting now.

Here's the surge-free results from a guy in NJ who just tested a 2003 R1150RT in the disconnected O2, stock Pink CCP plus BoosterPlug configuration. NJR1150RT. It adds to my confidence that a few percent richer-across-the-map AFR can cure most surging after a decent tune up.

Roger 04 RT said:

Here's the surge-free results from a guy in NJ who just tested a 2003 R1150RT in the disconnected O2, stock Pink CCP plus BoosterPlug configuration. NJR1150RT. It adds to my confidence that a few percent richer-across-the-map AFR can cure most surging after a decent tune up.

Click to expand...

That's great and encouraging news but two things:
- he's getting 30mpg! Ouch.
- it's an 1150, not an 1100. Different beast.

I do plan to try just disconnecting the O2 sensor after tuning the bike as is (new plugs and valve adjust + TB synch) I do that every spring anyway and then as needed.
But once I have it in the zone I'll unplug the O2 and see what happens at steady throttle.

Happy Wanderer said:

That's great and encouraging news but two things:
- he's getting 30mpg! Ouch.
- it's an 1150, not an 1100. Different beast.

...

Click to expand...

True, it is a single spark 1150 but they surge too.

The 30mpg is a question. I was getting about 45 last fall before I started. Working with that number says he's using a third more fuel. Seems like a questionable measurement. If it were 6 or 7% more that would be easier to understand. When I get some other stuff done I'll do a comparison on mine too.

Mine is on the way the R1100GS has smoothed out a bit with irid oovyium plugs hopefully this will bring it up a notch.

Booster Plug and fuel quality

I am curious of what is happening to Beemers in Europe and countries, (assuming) they do not have ethanol gasoline or EPA requirments.

just installed on 1999 R1100GS it has greatly improved the surging issues they are all gone or greatly reduced. The booster plug has an external sensor that will come in handy when riding in cold weather.

pat said:

I am curious of what is happening to Beemers in Europe and countries, (assuming) they do not have ethanol gasoline or EPA requirments.

Click to expand...

Whether or not to use a BoosterPlug isn't really related to ethanol. The inventor and producer is Danish and he uses the BP on his bike. The O2 sensor and three way catalytic converter have been required on motorcycles there by the Euro III standard I believe, since 2006 maybe earlier. Once a bike is running with an O2, the Open Loop fuel tables are set for 14.7:1 in the cruising range and Closed Loop with the O2 sensor enforces that ratio.

The 1100 series had a no catalytic converter option in Europe. The fuel table for that config is richer, a CO pot to trim carbon monoxide at idle is included, and those bikes don't seem to surge.

Roger 04 RT said:

Whether or not to use a BoosterPlug isn't really related to ethanol. The inventor and producer is Danish and he uses the BP on his bike. The O2 sensor and three way catalytic converter have been required on motorcycles there by the Euro III standard I believe, since 2006 maybe earlier. Once a bike is running with an O2, the Open Loop fuel tables are set for 14.7:1 in the cruising range and Closed Loop with the O2 sensor enforces that ratio.

The 1100 series had a no catalytic converter option in Europe. The fuel table for that config is richer, a CO pot to trim carbon monoxide at idle is included, and those bikes don't seem to surge.

Click to expand...

My Canadian 96 RT was identical to the Euro standard however which had a catalytic converter, no 02 sensor, no CCP and was equipped with a CO pot. Roger is right about the no catalytic option in Europe for the 1100 bikes. You could order one like that for some countries (Switzerland for example). You could tune the surge out of these bikes but mine needed the help of a Techlusion R259 which I eventually swapped out for a Booster Plug. They both helped relieve surging.

I have completed the retrofitting of my 2000 RT back to '95 - '96 standards and gone one step further. It now has no 02 sensor and no CCP. I does have a CO pot installed and trimmed to 1.5% O2 at idle. It also has a booster plug and a SuperTrapp muffler installed now as well.

I have not had the chance to do much test riding due to a pesky broken wrist but the one ride I did get in after the final tuning was done was very promising. Surging all but gone, loads of low end power, excellent throttle response and quite smooth on the highway in the short distance I traveled. (30km)

So it's looking good but I am holding back judgement until I can get a lot more riding in on this setup. Should be good to go in a week or less I hope. The only thing I will have trouble getting used to is that it is a bit loud! The bike sounds a lot meaner now and will take some getting used to. Makes you want to twist the throttle a lot more!