Engines evolve, the 1150 is different to the 1200 or doesn't that count?
Whether it's taken beyond it's limits, and the owners are beta testing it might be another discussion.
OH, Goody - a broken valve
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Engines evolve, the 1150 is different to the 1200 or doesn't that count?
Whether it's taken beyond it's limits, and the owners are beta testing it might be another discussion.
Of course engines evolve - we're either missing each others point or getting into a pi**ing contest here John
I said "Basically the boxer twin has gone as far as it can (or slightly too far) without some serious redesign of the cooling system and / or valve train. The current oil / air cooling system just can't cope with the specific output of the engine."
I stand by what I said. I know engines evolve, but the way the boxer twin is packaged makes it very hard for it to evolve further without some serious redesign and for designers to keep on increasing output. The heads need to breathe better / run cooler, but the boxer design includes some big compromises and trade off's.
The heads also need to be compact for ground clearance reasons. Water cooling or more cooling oilways will make them bigger and heavier, so what do you do? You could reduce the stroke and therefore the side-to-side dimension of the engine, but that'd increase revs and reduce torque - no good for a GS. Or you could raise the engine in the frame, but that'd make the whole thing even more top heavy and the pots would start to get in the way of the rider. Etc, etc, etc.....
I'll be interested to see how the engine does "evolve", but I still say that apart from out an out race engines where a lot of servicing and reduced reliability are tolerable, the boxer is reaching (or has reached) the end of its current path. I think the future will see either the abandonment of the boxer twin (almost inconceivable for BMW) or pegging of its output where it is (with some new valve train materials and/or cooling tweaks). Of course at the same time, they have to keep it affordable and compete with all the v-twins who don't have these evolutionary constraints.
I'd agree with that, how you keep the characteristics similar, and manage to convince people they "need" to upgrade to the latest engine etc muct be giving the designers a headache.
Personally, I don't think the on / off road GS needs any more power, so will the GS become more like the Tiger ie a tall on road bike?
Personally, I don't think the on / off road GS needs any more power, so will the GS become more like the Tiger ie a tall on road bike?
Just as a point of interest, when I was shopping for a 1200RT I was really interested in a RT in the dealers, it was fully kitted and had cruise control that I was really interested in.
When I asked if I could come down and look at it they said not at the moment, it was in the workshop with the R/side head off due to a ‘running problem’ LOL
When I asked if I could come down and look at it they said not at the moment, it was in the workshop with the R/side head off due to a ‘running problem’ LOL
Well I guess a valve head clattering around in the cylinder could be called a running problem
KevG
Registered user
Has anyone mentioned incorrect valve clearances yet?
If the ex. valve is not closing fully then the cylinder will run leaner than it should, The heat caused by the lean mixture will heat the valve which then expands and causes the mixture to lean off even more.
This theory would explain the backfiring on the overrun as air enters the exhaust through the unclosed valve.
If the ex. valve is not closing fully then the cylinder will run leaner than it should, The heat caused by the lean mixture will heat the valve which then expands and causes the mixture to lean off even more.
This theory would explain the backfiring on the overrun as air enters the exhaust through the unclosed valve.
Gabby
Registered user
Oh - so how do they explain 3 final drives then?
millard
Registered user
I was under the impression that the problem was showing up on the right hand cylinder more than the left, due, alledgedly to being left ticking over on the side stand?
Be a bit of a coincidence if all the right hand cylinders were incorrectly adjusted and the lefts were done properly.
Anyway, after our last wee off road foray I've got the answer so there's no need to fret anymore over it.
What I realised is that as I paddled through the mud due to my inferior off roading technique, the right hand cyl head was bashing buggery outta my right knee. I have long legs so this might not show up to all you wee vertically challenged riders.
So it came to me in a wee flash of inspiration that as the R/H cylinder is offset to the rear slightly that the cooling air is hitting it that wee bit later therefore causing all the overheating probs and making the valve heads lie down with heat exhaustion.
Prob solved!!
No, don't thank me, this has been a public service announcement
millard
Registered user
You've been riding it too hard. Your gonna get disqualified by BMW for enjoyin yerself too much.
[email protected]
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just one last comment on side/centre stand. Try putting the centre stand down on soft ground. It just digs in and then it falls over. On the side stand, its easy to put down a plate and position the bike over it before resting down on the stand. Don't fancy teetering around trying to get the centre stand over a scaffold plank in a muddy field.
swissrob
Registered user
haha no chance thats plausible
Pauly S
Registered user
I'm rebuilding one at the moment
What can i say, fecking haynes manual is crap, ive yet to suss the cam timing, the haynes book goes from heads in one page to clutch slave cylinder the next,who wrote this drivel? feckin noddy?
This one grenaded the right exhaust valves,bits of blown up bike everywhere, debris even went back into to air box.I had the bike delivered partially stripped which didnt help.
If i were to guess, i would say it would probably be a tight tappet, not allowing the valve to seat fully and conduct the heat away through the valve seat.( i dont go with the side stand bollix)
The tighter the tappet, the less pressure from the valve spring can drag the valve into the seat thereby conducting the heat away.
Remember these are a set of unique circumstances which are all compounding and causing valve failure, however, i guess the failure rate to be very low.Albeit expensive.
Over a period of several miles at motorway speeds i guess it wouldnt be difficult to build up immense heat in the valve head.But it doesnt explain why only the right side.Dunno..But ..
The other thing which springs to mind is the air filter is fitted in the air box to one side,i wonder if it is slightly a gnats weak on the right side due to the air filter being mounted on the right of the air box,coupled with a tight tappet occuring because of slight valve train wear, and all these factors adding up and causing the problem.There is defineately a concoction of factors here causing the blow up.I dont think its just one thing.
Either way the haynes book is shyte, dont buy it.
What can i say, fecking haynes manual is crap, ive yet to suss the cam timing, the haynes book goes from heads in one page to clutch slave cylinder the next,who wrote this drivel? feckin noddy?
This one grenaded the right exhaust valves,bits of blown up bike everywhere, debris even went back into to air box.I had the bike delivered partially stripped which didnt help.
If i were to guess, i would say it would probably be a tight tappet, not allowing the valve to seat fully and conduct the heat away through the valve seat.( i dont go with the side stand bollix)
The tighter the tappet, the less pressure from the valve spring can drag the valve into the seat thereby conducting the heat away.
Remember these are a set of unique circumstances which are all compounding and causing valve failure, however, i guess the failure rate to be very low.Albeit expensive.
Over a period of several miles at motorway speeds i guess it wouldnt be difficult to build up immense heat in the valve head.But it doesnt explain why only the right side.Dunno..But ..
The other thing which springs to mind is the air filter is fitted in the air box to one side,i wonder if it is slightly a gnats weak on the right side due to the air filter being mounted on the right of the air box,coupled with a tight tappet occuring because of slight valve train wear, and all these factors adding up and causing the problem.There is defineately a concoction of factors here causing the blow up.I dont think its just one thing.
Either way the haynes book is shyte, dont buy it.
socket086
Registered user
i think your wrong in thinking the valves are tight when i blew mine they were loose if you look closely they have a weld where the head of valve meets the stem and as far as i can tell they all seem to crack off there.
you might be on to someting with the air box as it mainly is the right side that gives up.
when mine went it started with a loud tapping noise after about 200 miles after checking valves went to a dealer and was told i had the wrong oil in it.
changed oil and still there 150 miles later i had the big bang shit everywhere.
the lesson i learnt is two fold 1 the dealers are shite and never ignore a funny new noise.
you might be on to someting with the air box as it mainly is the right side that gives up.
when mine went it started with a loud tapping noise after about 200 miles after checking valves went to a dealer and was told i had the wrong oil in it.
changed oil and still there 150 miles later i had the big bang shit everywhere.
the lesson i learnt is two fold 1 the dealers are shite and never ignore a funny new noise.
Don't blame Noddy, he wasn't riding it.
Get your man to buy one of these for the future, item two should help.
I've got one for mine which I use to help me sleep at night.
RH cylinder head trashed
I've just experienced the problem on my 2007 GS with 19,000 miles on the clock. Bike stalled whilst idling at a junction and wouldn't re-start. Engine stripped by BMW dealer who stated 'material failure of some sort, one of those things unfortunately!' Unbelievable that BMW accepts this as 'one of those things' on a bike of this reputation. What's the point of spending a small fortune on a 'prestige' brand and the expensive servicing if they aren't willing to hold their hands up to these design problems?
To make matters worse it's now two and half months since the strip down and they still can't get all the spares because 'there's no call for cylinder heads except for accident damaged bikes'! I've completely lost faith in BMW and the bike which is a shame because I've been all over Europe on it and had great rides in Italy, Rumania etc.
Looks like it's time to change the bike when I eventually get it back?
I've just experienced the problem on my 2007 GS with 19,000 miles on the clock. Bike stalled whilst idling at a junction and wouldn't re-start. Engine stripped by BMW dealer who stated 'material failure of some sort, one of those things unfortunately!' Unbelievable that BMW accepts this as 'one of those things' on a bike of this reputation. What's the point of spending a small fortune on a 'prestige' brand and the expensive servicing if they aren't willing to hold their hands up to these design problems?
To make matters worse it's now two and half months since the strip down and they still can't get all the spares because 'there's no call for cylinder heads except for accident damaged bikes'! I've completely lost faith in BMW and the bike which is a shame because I've been all over Europe on it and had great rides in Italy, Rumania etc.
Looks like it's time to change the bike when I eventually get it back?
Pauly S
Registered user
Trouble is you have a nine year old bike,and no dealer on the planet will be interested in it. Just rebuild it with new valves, make sure you have the latest software in it, and you'll be fine.As i recall there was a problem with the quality of the valves at the time, but its all sorted now.Just fix it and ride it.All modern machinery has problems, thats the way it goes, it doesnt matter if the bike is 5 grand or 20 grand they all break down.
You had some nice rides on it, so fix it and have some more.
You had some nice rides on it, so fix it and have some more.
Pauly S
Registered user
Ditchy... I miss ya dude.
Bendy toy
Registered user
A used head will do the job fine. Get the dealer to fit brand new valves.
Closed up valve clearance will hold a valve open end result is burnt seat and valve head. Running a weak air fuel mixture along with low octane fuel can really cook the exhaust valves. Sooner or later the valve falls apart.
The 1150 is supposed to have new exhaust valves at some point. The 1200 apparently not.
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