BMW R1200R R1150R/T F800 K1200R R1100R/T R1250R RnineT Message Board

So during my last ill-fated maintenance job (see post "cylinder head removal"), I just happend to have the pen light nearby when I pulled the spark plugs and decided to take a look into the combustion chamber. Right away I noticed what looked like a lot of carbon buildup - the top of the piston was completely covered - looked like lava rock on there for goodness sake.

Has anyone noticed this before? I keep up with the maintenance (incl. air filter) and almost always run premium, so I'm a little stumped.

Any suggestions on cleaning up the combustion chamber? Also, I saw a post over on advrider that suggested checking the pressure during a compression test - can anyone here suggest a good compression tester for this engine (it's an '04 r1150r) and what constitutes "proper" pressure for the cylinder?

Thanks in advance,
Terry

90 miles per hour in 6th gear for 30 minutes every day.

These bikes do accumulate carbon. Seafoam is a popular fuel additive that many swear by to clean up the carbon. Just don't exceed the reccommended dosage.

Boxer wrote:90 miles per hour in 6th gear for 30 minutes every day.

This technique works for me, as well. It cures detonation and will improve engine idle and starting. Check and gap your plugs after the high speed carbon removal riding.

def38 wrote:

Boxer wrote:90 miles per hour in 6th gear for 30 minutes every day.

This technique works for me, as well. It cures detonation and will improve engine idle and starting. Check and gap your plugs after the high speed carbon removal riding.

90-MPH in 6th gear is only around 5000-rpm. You gotta take that mutha up to the redline. It's a boxer twin and not that silly ass American V-twin engine. It can take the high RPM run just fine. But yes, must blow that carbon out with high speed runs. Or at least that's what I'm telling myself anyway.

I had overheard my BMW service manager telling a customer to get those revs ups while going through the gears as well to get the carbon buildup out. I have done this and I do notice less pinging even with 89 octane.
Plus its alot of fun too!!

I add some Seafoam to mine occasionally. Here in Va it's too expensive (not to mention dangerous) to make too many high speed runs. Va just recently enacted "Civil Remedial Fees" for certain traffic offenses. It's a little obscure but bottom line is a speeding ticket could be very expensive not only in the immediate but also long term. Also oddly enough the fines only apply to Va residents. So you guys who live here be careful!

Wayne
03 r

+1 on the high rpm runs to keep your combustion chambers clean. If your bike is an '04-spec, as you say, it should be a twin spark, and these have a more complete burn and are far less prone to carbon build-up. In theory, at least.

At the very least, you should be going out of your way to use gasoline that has techron added as an additive. If you are in the US, that would be Chevron, and now Texaco has begun adding it to it's pump blends as well. Techron flat out works to keep your combustion chambers and valve guides and seals clean. Not just an opinion, you can look it up.

lol - thanks for the good advice everyone. Good to see that "blowing the carbon out" is as much valid mechanical advice now as it was when I was getting yelled at by the neighbors when we screamed by on the bikes/quads.

I hear ya' towerworker - the Washington State Patrol was all over the news this week "gloating" about how they had managed to raise the cost of all speeding infractions. About the only place I feel reasoably safe (both physically and financially) sustaining 90+ for any amount of time is when I'm lucky enough to be rolling through south eastern oregon and into Nevada - and unfortunately that's only a couple times a year.

I'm still a little suspicious about driving habits being the cause though - most of my miles are commuting, and I rarely drop the r's below 4k - never know when you'll need peak HP to get out of the way of an idiot in a cage. I think I'll catch up on the seafoam threads and perhaps try a little of that; in addition I'll see if I can't find that redline a few times per week. My local station is a chevron, so the majority of gas I use is techron enriched.

Anyway, I'm content until the plugs come out again next year, I'll post on how things look.

-Terry

priapismic wrote:+1 on the high rpm runs to keep your combustion chambers clean. If your bike is an '04-spec, as you say, it should be a twin spark, and these have a more complete burn and are far less prone to carbon build-up. In theory, at least.

At the very least, you should be going out of your way to use gasoline that has techron added as an additive. If you are in the US, that would be Chevron, and now Texaco has begun adding it to it's pump blends as well. Techron flat out works to keep your combustion chambers and valve guides and seals clean. Not just an opinion, you can look it up.

Techron does work well. It is about 50% Stoddard colvent, a blend of distilates that clean up deposits. A dose in the fuel tank works well. Follow recommendations...do not add the whole can. Use it shortly (200-300 miles or a tank or two) before you plan to change your engine oil. The oil does end up harboring much of the soot that comes from the Techron.