Coke habit!

[katanamangler]

Which fuel is Sir using?

I'm using the highest octane shell fuel at the moment. Don't know what it was run on before though. From speaking to the the 2 previous owners the bike has always been ridden very gently- rarely above 80mph. The first owner used the bike on a daily 6 mile urban commute so I think its had a fairly easy life. Maybe too easy.

I know these bikes burn oil in the early years and if the resulting carbon deposits and glaze have accumulated over time they can be very difficult to shift.

 

[Hay Ewe]

i like the idea of carbon build up
I would also like to add oil build up in the inlet tract. Reason is that if it was constantly filled to the top level, the excess oil would vent to the airbox and then in to the inlet tracts and valves.

I would suggest that all long term 1150 owners know that the comfortable oil level is half full on the sight glass, and then it doesn't vent any to the airbox.
Cleaning the inlet tracts, throttle bodies and cyclinder heads is fairly easy, cleaing the airbox not so much - DAMHIK

I think that if you let the oil level stabilise, ride it how you like it, the inlet system will self clean, and combined with what you are doing / previoulsy done, it will come good

Hay Ewe

 

[Packer]

The first owner used the bike on a daily 6 mile urban commute so I think its had a fairly easy life. Maybe too easy.

I know these bikes burn oil in the early years and if the resulting carbon deposits and glaze have accumulated over time they can be very difficult to shift.

Unless the first owner also used it for trips, track days and general thrashing the early part of it's life was about as bad as it could be. Loads of miles below optimal operating temperature, likely burning quite a lot of oil by which I mean > 1 ltr/1,000 miles.

On my 7½ mile each way commute my 90,000 miler has always burnt oil, after 20,000 or so miles it dropped to around ½ ltr/1,000 miles. Do the equivalent miles of 10 weeks commuting in one weekend and there is no discernible drop in the oil level.

 

[Steptoe]

My fear is that there might be a burnt exhaust valve or seat. Time will tell.

.

The bike wouldn't run on the cylinder with the burnt exhaust valve.

Ok, carried out a compression test this morning and both pots are reading 175psi. Now to me that seems a bit high, which would support my carbon fouling theory.

What's a normal healthy reading for the R1150GS ?

How can carbon increase the compression by such a huge amount ? If the compression was that high you'd be flying along like a supercharged bike with some pinking in the lower gears, not having problems

I'd be carefull taking a PSI reading from a compression tester as a precise and exact measure. They all vary on readings depending on the make of tester.
The point is that you can compare readings from side to side, and obviously, tell if it's an absurdly low reading.

 

[Dr Bones]

I always wondered about the wisdom of feeding water through the induction system of a four stroke engine to clean it out, until my mates bike blew it's head gasket the other year. When we disassembled the engine the piston crown and valves on the cylinder where the gasket blew were spotlessly clean. The other piston and valves were black and coked up.

I saw this video a while back of a guy decoking his Mazda RX8 using WD40 and water with a tube connected to the vacuum ports of the induction system


http://www.youtube.com/watch?feature=player_embedded&v=ETYmhdSd-Sk

It made me think that perhaps the same could be done using the throttle body sync vacuum ports on the R11xx series bikes?

 

[MattW]

I always wondered about the wisdom of feeding water through the induction system of a four stroke engine to clean it out, until my mates bike blew it's head gasket the other year. When we disassembled the engine the piston crown and valves on the cylinder where the gasket blew were spotlessly clean. The other piston and valves were black and coked up.

I saw this video a while back of a guy decoking his Mazda RX8 using WD40 and water with a tube connected to the vacuum ports of the induction system


http://www.youtube.com/watch?feature=player_embedded&v=ETYmhdSd-Sk

It made me think that perhaps the same could be done using the throttle body sync vacuum ports on the R11xx series bikes?

Hmm.
The Mazda RX'es are wankel rotaries - more like 2 strokes. I'd be very wary of deliberately chucking incombustible fluids into the intake of a four stroke - a recipe for expensive hydraulic seizures if you get it wrong.

Just take the head off - about half an hour if that (assuming the exhaust headers come off without snapping the studs ). There's an excellent how to from Steptoe in the font of all wisdom.

 

[topcat2006]

Hmm.
The Mazda RX'es are wankel rotaries - more like 2 strokes. I'd be very wary of deliberately chucking incombustible fluids into the intake of a four stroke - a recipe for expensive hydraulic seizures if you get it wrong.

Just take the head off - about half an hour if that (assuming the exhaust headers come off without snapping the studs ). There's an excellent how to from Steptoe in the font of all wisdom.

Is it that much different than doing the Redex treatment?

Tom

 

[Dr Bones]

Hmm.
I'd be very wary of deliberately chucking incombustible fluids into the intake of a four stroke - a recipe for expensive hydraulic seizures if you get it wrong.

I tend to agree Matt, but I have to say that on my mates TDM850 which blew the cylinder head gasket, I couldn't believe how clean the cylinder and valves were on the side where the gasket blew. I've never put anything down the intakes other that carb cleaner occasionally. But the whole seafoam thing does get you thinking.

 

[katanamangler]

I guess there are lots of ways to de-coke a combustion chamber - water torture, solvents and that Canadian terraclean system that's over here now.

If it stubborn enough I guess for the price of a couple head gaskets, manual removal would be safest and most thorough backstop if all else fails. At least that way you can check the valve seats.
I'll give it another AMSoil treatment first and let it soak a little longer and change the oil afterwards and see how it goes.

I've been working in London all week and I'm off to Europe shortly so it will have to wait until work allows for some more workshop time.

I found a thread on another site which had a copy a letter from BMW to all US dealers back in 2003 authorising cylinder head de-coke and barrel de-glazing under warranty for the 1150GS if customers were experiencing excessive pinging. I cant find the thread now.

 

[katanamangler]

The bike wouldn't run on the cylinder with the burnt exhaust valve.



How can carbon increase the compression by such a huge amount ? If the compression was that high you'd be flying along like a supercharged bike with some pinking in the lower gears, not having problems

I'd be carefull taking a PSI reading from a compression tester as a precise and exact measure. They all vary on readings depending on the make of tester.
The point is that you can compare readings from side to side, and obviously, tell if it's an absurdly low reading.

Yeah,I have to say I was surprised by the PSI figure but my gauge has always been pretty reliable in the past. Supercharging
As you say the main thing is the readings were equal.

 

[katanamangler]

By way of an update: I finally got some time in the garage last week and I treated the cylinders with amsoil power foam and let is soak into the hot chambers for a good couple of hours. I took the bike for a short run with some ATF in the oil on on my return then dropped the oil changed it for fresh 20/50 and a new filter. I also fitted and upgraded cam chain tensioner on the left hand side

On Friday I loaded up my camping gear and did a 700 mile round trip which included at least 400 motorway miles. I took some techron with me and added the prescribed dosage to each tank of fuel. By the middle of the trip the bike was running brilliantly and it ran that way for the rest of the trip. Pulled like a train all the way.

It was great to just enjoy the bike and eat some miles.

 

[ghiribizzo]

Remember you said you weren't going to get too involved with this bike..?

 

[ghiribizzo]

Remember you said you weren't going to get too involved with this bike..?

 

[katanamangler]

That was the plan but there are 3 possible reasons why I haven't ( answers on a post card):

1. I am an obsessive compulsive
2. Apparently some people can't tell that a bike isn't running right and I'm not one of them.
3. I just love buying expensive new parts and tools and whiling away my spare time in the garage when I should be riding my bikes or drinking beer.