R1150 Twin Spark Conversion Experiences

[tdomek]

I am contemplating the purchase of an '02 or '03 R1150 R or RT. I am planning to ride it for this season and over the winter installing a twin spark conversion kit. Any experiences and insights concerning the purchase, installation and results of such an endever would be greatly appreciated

[36691]

Why would you not just buy a twin spark engined bike from the start
Martin buck

[tdomek]

A couple grand difference in price that I just do not have. I GOTTA HAVE a newer bike! My old airhead RT has over 200,000 miles on her and I really want to get back into touring again!

[BubbaZanetti]

why do you want to convert a motorcycle you haven't even purchased yet. seems like it would make sense to ride it first then determine if the surging is annoying to you. a 2 spark conversion requires a lot of things other than new heads and doesn't always cure surging. i'm guessing that is your main reason for avoiding a single spark model??

[HFD190]

I had the same situation (in my mind) as you last fall. I wanted a twin spark but was limited by funds. I ended up with a slightly used 03’ 1150RT. I guess that I had read someplace how great the twin spark update was, and I thought to myself that the single must be therefore terrible. It’s NOT! There is some surging, which I wouldn’t even consider a mild distraction. Good Luck…

[PacWestGS]

JMO Other's MMV, a waste of money, and not worth the trouble to install.

The two-spark models don't have that much noticible power, or fuel mileage increase. They do however lower exhaust emissions.

I'm with Bubba, ride it first fix it later if you need to at all.

Surging can be fixed in many cheaper ways, if the bike you find even does it to begin with.

Find the right bike that fits your pocket book.

Doc

[mojoviously]

The techlusion totally resolved all surging on my 03 1150RT - it's smooth (with carbs sync'd) and very fast & capable of twisties with no effort. Great mileage, fair priced bike for what you get. Wouldn't ever consider converting it to twin spark, just no need. My 2 cents. :clap

[BradfordBenn]

My 02R1150RT has not surged. I would say before you buy test ride and see if it surges.

[mosrrt]

ok I am going to ask this question ...I am new to BMW so don't be too hard on me ...ha ha . What is the "twin spark" ??
Mike

[BradfordBenn]

ok I am going to ask this question ...I am new to BMW so don't be too hard on me ...ha ha . What is the "twin spark" ??
Mike

In 2003 BMW released oilheads with two sparkplugs. The idea being that they would be able to vary the timing on them to compensate for different fuel burning times at different engine speed.

[PUDGYPAINTGUY]

In 2003 BMW released oilheads with two sparkplugs. The idea being that they would be able to vary the timing on them to compensate for different fuel burning times at different engine speed.


And I thought that it came out after beemer became majority shareholders in Bosch...hehehehe

[rinty]

mosrrt:

The reason for the second spark plug is that boxers have never combusted efficiently at the periphery of the combustion chamber, being the area commencing at the cylinder wall next to the outer rim of the piston, and then towards the centre a few millimetres, all the way around.
BMW sought to deal with it by placing a second spark plug in that zone, but apparently the main reason they did that was to improve emissions. The engine output change is one horsepower. And as Brad mentioned, the timing of each plug's spark can be varied.

Rinty

[PUDGYPAINTGUY]

I rode a single plug and my own dual plug and very little difference really to validate the extra money. As an earlier post stated that the surging if and when can be solved by inexpensive means and adjustments, that would eliminate the need to buy a conversion. Spend the money on a tent and gear and enjoy your new steed. Good luck and carpe beemum!

[BubbaZanetti]

or you can just buy an S, they never surge

[tdomek]

why do you want to convert a motorcycle you haven't even purchased yet. seems like it would make sense to ride it first then determine if the surging is annoying to you.
Which is why I said I would ride it this season and do the conversion later. Yes, surging would be the main reason for the conversion, but the CLAIMED increases in power and fuel economy were also considerations. I have ridden several different oilheads, about 2000 miles in total, and they all surged. All single spark, no "S" or "C" models. Neither fits my needs or pushes my button, so they are not part of the discussion. The scuttlebutt is the twin spark 1150's don't surge and do not require as much futzing to keep it that way. And I am all for less futzing.

I'm just askin...

[BubbaZanetti]

All single spark, no "S" or "C" models.


yeah, these tend not to surge cause they are different engines than the rest of the line-up, the C is much different, the S has different cams and produces a little more hp. i think if you can find a single spark with very little surging, then you can make it go away with less fuss than trying to make it twin spark. as others mentioned, techlusion, but also a good synch and valve adjust and maybe a new airfilter. there is also TPS (throttle position sensor) adjustments you can do.

hp and fuel economy gains are going to be marginal at best.

good luck!

[PacWestGS]

Tom,

I have an '02 R1150GSA (single spark) never surged. I got an average of 42-45mpg and was very happy with it.

Then I started to read all these posts about the engine management and what BMW did to satisfy the EPA, when I heard about the 'Techlusion R-259' I didn't buy it to fix surging, I installed it fix or return to how BMW designed the motor to run.

I am happier with the performance but my mileage dropped to 38-42 for same average commute. It's easy to turn off if mpg becomes an issue.

Good valve adjustment and TB sync will fix most but sometimes 're-mapping' the Motronics is necessary.

HTH
Doc

[kbasa]

Single plug oilheads are very, very sensitive to tuning. Careful valve adjustment and throttle body sync will almost always render a non surging bike.

Check the AdvRider Hall of Wisdom for OVAD. It works and dual plug heads aren't a necessity, IMHO.

[rinty]

After the Luftmeister years, I don't think I'd want anyone except BMW drilling extra holes in my bike cylinder heads.

Rinty

[tdomek]

I want to thank all the good folks who responded to my post. Your insights and experiences have made me much better able to make a value judgement about twin sparking.
Now if only I could get this divorce finalized and the house sold... :bluduh