"If it ain't broke".... 2002 1150GS

[docgonzo]

My 1150 GS now has 89,000 local miles on it. Commuting and day rides for 10 years. No road trips of any merit, due to work and family stuff. I ride the bike hard. In all kinds of weather.

Question: the bike has never run better. Starts easily, idles nicely, accelerates like a scalded cat. But I haven't had the throttle bodies "synched" recently, or adjusted the valves. Oil changes and fluids changed regularly. Keep good rubber on the big yellow pig. Rub off the dirt when required.

So, if it ain't broke, does that mean the throttle bodies are synched and the valves are fine?

My feeling is that after all the regular maintainence valve adjustments over the years, the valves are now "stretched" about as far as the metal will go, and don't need as frequent adjustment. Foolish self delusion?

[Hay Ewe]

It doesnt hurt to check
The airplane you get on, would it be ok if they hadn't done a check because it was running just fine?

Hay Ewe

[jdub]

I stretched valve clearance checks out to every 12k miles quite some time ago (114k miles on the bike now), and rarely find any of them needing even minor adjustment but I still check 'em just to be sure. Since TB synch is all about getting the engine as smooth (balanced) as possible, I only do that when I can feel that it needs done (once in the last 45k miles or so).

[Multiplicity]

Throttle cables will stretch less and less and that could be why the TB's are still close.

[The Walrus]

Originally Posted by jdub

I stretched valve clearance checks out to every 12k miles quite some time ago (114k miles on the bike now), and rarely find any of them needing even minor adjustment but I still check 'em just to be sure. Since TB synch is all about getting the engine as smooth (balanced) as possible, I only do that when I can feel that it needs done (once in the last 45k miles or so).

........yup........

[Twilight Error]

Could go either way.

I just tore into my 1150 for a new clutch and a leaking right head gasket. I figured while I've got one head off, I'll pull the other and clean the carbon off that one too.

I'm glad I did, I found a valve that was burned and not seating properly.



Prussian Blue tells the story:


The valve is toasted and is only a matter of time before it left me stranded somewhere.



This GS has 103k miles.

[GS Addict]

Originally Posted by Twilight Error

Could go either way.

I just tore into my 1150 for a new clutch and a leaking right head gasket. I figured while I've got one head off, I'll pull the other and clean the carbon off that one too.

I'm glad I did, I found a valve that was burned and not seating properly.



Prussian Blue tells the story:


The valve is toasted and is only a matter of time before it left me stranded somewhere.



This GS has 103k miles.

If you plan to keep the bike get both heads done. New guides, new exhaust valves, grind/lap intakes, new seals.
Good for another 103k

[Twilight Error]

Originally Posted by GS Addict

If you plan to keep the bike get both heads done. New guides, new exhaust valves, grind/lap intakes, new seals.
Good for another 103k

I'm going to buy a set of heads from the Beemer Boneyard and have them redone. Time and budget are forcing me to half-ass the repair now, but I do plan on keeping it for another 100k miles.

[bemiiten]

Originally Posted by docgonzo

My 1150 GS now has 89,000 local miles on it. Commuting and day rides for 10 years. No road trips of any merit, due to work and family stuff. I ride the bike hard. In all kinds of weather.

Question: the bike has never run better. Starts easily, idles nicely, accelerates like a scalded cat. But I haven't had the throttle bodies "synched" recently, or adjusted the valves. Oil changes and fluids changed regularly. Keep good rubber on the big yellow pig. Rub off the dirt when required.

So, if it ain't broke, does that mean the throttle bodies are synched and the valves are fine?

My feeling is that after all the regular maintainence valve adjustments over the years, the valves are now "stretched" about as far as the metal will go, and don't need as frequent adjustment. Foolish self delusion?

I'd say you can double the valve adjustment interval if your personally familiar with how much they have needed adjustment in the past. I'm assuming your letting the shop do the deed so unfortunately, the adjustment is only as good as the last guy set them. I wouldn't let a shop work on my bike for free, but that's just me.

[Jim Moore]

TE, what are you seeing there that suggests a burnt valve? I know nothing about the insides of engines.

[Multiplicity]

Originally Posted by Jim Moore

TE, what are you seeing there that suggests a burnt valve? I know nothing about the insides of engines.

If a valve gets tight it can burn. Time and miles are why this one is in this condition, IMO.

[def]

Originally Posted by GS Addict

If you plan to keep the bike get both heads done. New guides, new exhaust valves, grind/lap intakes, new seals.
Good for another 103k

Your photos suggest that there was wet carbon present in the combustion chambers. This could be due to several factors. How do the piston tops look? Same wet carbon? If so, I would continue to look for a source for oil in the combustion chambers.

New exhaust valves and stem seals with a valve job according to the specs in the BMW REProm. One exhaust seat looks like it has a nick in it. Take the heads to an expert who knows how to shrink new valve seats into the alloy heads and perform the multi angle valve seat grinding.

[GS Addict]

Originally Posted by def

Your photos suggest that there was wet carbon present in the combustion chambers. This could be due to several factors. How do the piston tops look? Same wet carbon? If so, I would continue to look for a source for oil in the combustion chambers.

New exhaust valves and stem seals with a valve job according to the specs in the BMW REProm. One exhaust seat looks like it has a nick in it. Take the heads to an expert who knows how to shrink new valve seats into the alloy heads and perform the multi angle valve seat grinding.

My photos? I did not post any.

[docgonzo]

Originally Posted by bemiiten

I'd say you can double the valve adjustment interval if your personally familiar with how much they have needed adjustment in the past.

Thanks everyone for your opinions. I'll probably wait with throttle body synching for a while, since the bike is idling and running nicely. I'll check the valves in the springtime to make sure they are not out of whack. I'm gonna bet they are pretty much in spec., as they were the last time they were checked. These old GSs, once broken in, seem to be pretty tough machines. Took the old yellow pig about 25,000 miles before it stopped burning oil, so I guess they design them to break in slowly, but last longer then most bikes. Stock seat became comfortable about the same time!

[rdwalker]

Originally Posted by Twilight Error

... The valve is toasted and is only a matter of time before it left me stranded somewhere.
...
This GS has 103k miles.

I think that's crap. Barely 100k on the clock and you already have engine trouble? I'd go complain to the dealer.

Sorry... Could not resist...


However: would that type of failure show up on an external check? That is, with routine maintenance, such as valve-clearance adjustment?

Or, if you did not coincidentally pull the head, would you get a nasty surprise without any advance warning?