2002 R1150RT - Purging the surging.

[steelerider]

Purging the surge.
I recently bought a 2002 R1150RT. The bike had 1 owner, and 38K on the clock with a “full service history.” I did a ton of research online before taking the plunge and was well aware of the dreaded “surge” issue with this bike. It seems that there are 2 camps associated with this problem – those who never felt it, and those who have spent hours and hours obsessing over the problem trying to get rid of it. After owning the bike for a few days,  I definitely did notice that at steady throttle (just on)  and low speed there is a tendency of the engine to hunt and surge. So began the process of trying to get it out.
Something to note, it is important that we differentiate between an absolute fueling / engine surge problem  and driveline lash issue. Any shaft driven bike (or machine) that is coupled directly through a hard transmission to the engine will experience some form of lash, or “pushback.” You can usually feel this when you release the throttle abruptly in a low gear. The power output of the engine rotating the wheel is now send the other direction back into the engine (like engine braking) At minimum throttle settings, this can result in a push / pull oscillation between the engine output and the wheel input. You feel it more on a shaft driven bike since there is little slack in a hard shaft to absorb this oscillation. A chain driven bike has some stretch and slack to soak the “push and pull.” A lightweight chain is able to react much faster to this.  In large industrial equipment I work with, if there is a manual tranny, there is usually a flexplate with springs, coupled to the shaft to ease reverse input and shock load into the transmission.  Every BMW boxer I have ever ridden has a minor form of this phenomenon. A hard direct shaft drive with little slack and a high compression boxer engine with 2 large pistons doesn’t help.  
Needless to say – at low RPM’s around town as a result, the R1150RT is not the smoothest bike. However the real issue most people complain about on the RT is a fuel delivery related surge. This is caused by very lean fueling, for US emissions, (made worse by ethanol based fuels that run even leaner than real gas.) There is a ton of resource about this on-line, closed vs open loop etc. I’ll let you find it.
My bike came with a Techlusion EFI module, which tells me that the P/O was fighting the same problem; still the bike surged with this mod.
In short, this is what fixed 95% of the issue for me.
1: A and critical valve adjust.  Mine was supposedly done at the 36K mile service on a bike with a “complete service history”. All the valves were way out – all way too tight.
2: Complete throttle body clean and sync – they were full of 10 years of junk, and were way off.
3: New Autolite 3923 plugs – huge difference, just do it for $4 you can’t go wrong. I won’t pretend to understand the science behind it. I just know the bike idles better, starts easier and runs smoother. My theory is that the slightly hotter plugs result in a more complete,  smoother combustion.
4: Pull the Pink CCP plug and throw it away – much to say about this online. Everything from “you will destroy your cat” to “it’s the best mod ever” All this is, is a jumper to tell the ECU to select a very lean map for US emissions. When you pull it, it reverts to a richer map.  Bikes delivered overseas (Australia) do not have the pink CCP installed. When I pulled this thing, instant improvement. The surge was gone. Completely.  The only issue being that the bike felt a bit lethargic at higher RPM. I just added a little more fuel back in with the Techlusion to fix the problem, (yellow and red pot’s for those who want to know)

Lessons learned –
Do the valve adjust and TB sync yourself. Get the feeler gauges and do it right. Take your time. Your dealer will not, and can’t afford to take an hour to do it. Close enough is not good enough. My dealer can’t even get the fairing back on properly without scratching it up, and/or forgetting the screws under the seat – yes this already happened.  How then can I trust them to do a proper job with the valves and a good TB sync, and then charge $400 for a 6k maint on a 10 year old bike? Yeah right.
Pull the CCP. Throw it into the river. Enjoy your bike. My opinion is that this causes no harm to the engine or cat. I pulled the plugs last week, and they looked good. No black soot. Tells me the engine is not running too rich. Just rich enough and probably still quite lean. Change the plugs. The autolites work well for this engine.
Getting rid of the surge is going to cost you MPG. No doubt about it. Any fuel you add is going to cost you more. I get about 36- 41 mpg. I would rather pay a little more for a properly running bike with smooth power than hate it every time I ride.  It’s worth it. If you want 50 mpg – be prepared to run a lean, surging pig.
Good luck – of course YMMV!

[viffergyrl]

+1

I have a Techlusion as well plus I pulled the Pink CCP plug. Mileage is in the high 30s, but the bike is just plain happier and runs so much better.

Gonna try the sparkplugs and I'm due for the valve check/adjust plus the throttle body sync. But I won't be taking it to the dealer.  

[steelerider]

Well - I actually got rid of the techlusion today, I keep finding that with the CPP plug pulled I cannot get it to fuel smoothly. Its just so abrupt. No amount of combinations between pots seemed to get it the way I want. So it's coming out. The bike is  very slightly down on power, but much smoother without it, and still no surging. Plus, I got tired of standing on the side of the road tweaking the darn thing, more than I was riding. I have come to 2 a few conclusions about the RT
1: Around town, its out of its element. The Fuel injection on the bike just seems so ragged. Likely due to the fact that when it was built in 2002, those were the early days of bikes being fuel injected. The boxer engine, certainly from that era is just not the smoothest thing around. But, what does one expect from two huge pistons, and a large displacement. The combination of that, plus a shaft drive, and a dry clutch all add up to make it a pig in town. On the highway? Best bike ever. A good clip on the back roads, it handles like a dream. I would ride it across the country in a heartbeat.
2: After riding the beemer for the past month, I took my 09' Sprint ST out. It is the smoothest bike I have ever ridden. No surging, smooth in traffic , more than enough power. I have a completely new appreciation for it! Would I take it on a long trip like the BMW. No. But thats why I own the RT now.
One to go far and one to go fast.

[viffergyrl]

Good to know - thanks for the input!

[ripdaddy]

when it was built in 2002[/quote]

    Consider that it took BMW nine years to even half-way address the surging with a dual-plug motor.  When a friend, who owned a Honda ST1100, took my '95 R1100RS for a ride he said, "No offense, but I just don't get what you like about that bike."

[Roadscum]

Well - I actually got rid of the techlusion today, I keep finding that with the CPP plug pulled I cannot get it to fuel smoothly. Its just so abrupt. No amount of combinations between pots seemed to get it the way I want. So it's coming out. The bike is  very slightly down on power, but much smoother without it, and still no surging. Plus, I got tired of standing on the side of the road tweaking the darn thing, more than I was riding. I have come to 2 a few conclusions about the RT
1: Around town, its out of its element. The Fuel injection on the bike just seems so ragged. Likely due to the fact that when it was built in 2002, those were the early days of bikes being fuel injected. The boxer engine, certainly from that era is just not the smoothest thing around. But, what does one expect from two huge pistons, and a large displacement. The combination of that, plus a shaft drive, and a dry clutch all add up to make it a pig in town. On the highway? Best bike ever. A good clip on the back roads, it handles like a dream. I would ride it across the country in a heartbeat.
2: After riding the beemer for the past month, I took my 09' Sprint ST out. It is the smoothest bike I have ever ridden. No surging, smooth in traffic , more than enough power. I have a completely new appreciation for it! Would I take it on a long trip like the BMW. No. But thats why I own the RT now.
One to go far and one to go fast.

Why do yiu say "NO" to taking the Sprint on a long trip? Is it an ergonomics/comfort issue?

Regards, Paul

[steelerider]

Paul -
The Sprint is a great bike. Probably the best all round I've ever owned. But my wife hates the pillion position on the back. It sits her really high. I bought the beemer so we  would both be a little more comfy.

[Roadscum]

Paul -
The Sprint is a great bike. Probably the best all round I've ever owned. But my wife hates the pillion position on the back. It sits her really high. I bought the beemer so we  would both be a little more comfy.

I understand. For me a shaft or belt drive is my touring choice to rid myself of the minor maint. of the chaain and the oil mess on the bike and clothing. I  too luv those trippples!!!

Regards. Paul