Right hand cylinder destruction

My 2005 1200GS also mangled the right hand cylinder in a similar. Rebuilt by Rainbow with a fair bit of goodwill thrown in because they sold it me. Once fixed I moved it on via a trade in with same dealer.

Much talk about oil starvation amongst the ‘cognoscenti’.
 
How many 2005 bikes were sold? How many had this issue?

It happens, obviously only to a small percentage of the total bikes sold, but that’s still a lot of bikes.
It even hapoens to intelligent riders with mechanical sympathy as well as to everyone else who are apparently brainless.
 
its very common that poppet valves that have had a hard life at high revs / high miles can just fail

as suggested the sodium filled ones were always a mistake - Laverda Montjuic, Citroen SM and 4 stoke Motocross bikes sill on the original valves at 10k miles (2500hrs) being the most obvious candidates
MCN or one of the big UK mags had a BM twin cam drop a valve as it hit 98k miles - the article went on to say its a std feature at those miles - of course if you ride around at 4k, then the valves have done nothing in life - ones that stay closer to 8k rpm have done way more than twice the effort - the stress on the valves at high revs is more like ten times as much
 
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It happens, obviously only to a small percentage of the total bikes sold, but that’s still a lot of bikes.
It even hapoens to intelligent riders with mechanical sympathy as well as to everyone else who are apparently brainless.
But a small percentage is still a small percentage.

What is the failure rate? 1 in 10,000?, 1 in 1000, 1 in 100 of all bikes sold.
 
But a small percentage is still a small percentage.

What is the failure rate? 1 in 10,000?, 1 in 1000, 1 in 100 of all bikes sold.

I can only judge on my personal experience - a rough guess out of the 400/500 different 1200cc bikes I’ve worked on ( not including normal service jobs) around 50 of those jobs involved a dropped a valve on the righthand side.

Perhaps I am just smarter and more mechanically sympathetic that the average brainless Tosser.

I have no idea of the average intelligence of those owners, unlike your nonjudgmental good self.
And I have no idea how you work out the correlation between intelligence and metal fatigue of an exhaust valve when there are so many various and random circumstances.
Back in the day BMW used to recommend changing the exhaust valves on the large R80/100 twins when the bikes had covered around 70k miles as there was a tendency for the head of the exhaust valve to drop off.
Maybe BMW based this at the time on the average intelligence of the owners and not the fact the head of the valves were welded onto the valve stem on the larger CC models..
 
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I can only judge on my personal experience - a rough guess out of the 400/500 different 1200cc bikes I’ve worked on ( not including normal service jobs) around 50 of those jobs involved a dropped a valve on the righthand side.



I have no idea of the average intelligence of those owners, unlike your nonjudgmental good self.
And I have no idea how you work out the correlation between intelligence and metal fatigue of an exhaust valve when there are so many various and random circumstances.
Back in the day BMW used to recommend changing the exhaust valves on the large R80/100 twins when the bikes had covered around 70k miles as there was a tendency for the head of the exhaust valve to drop off.
Maybe BMW based this at the time on the average intelligence of the owners and not the fact the head of the valves were welded onto the valve stem on the larger CC models..
So approx 1 in 10 of your repair jobs?
 
80K on mine. I'm living on borrowed time :oops:. Scared to take it out now :rolleyes:
 
Which is higher ratio than other
“common” expected failures on that particular model
Maybe but in the grand scheme of things how big is the problem in reality? - however I bet there are many more common failures on the GS of that generation. A very common fail on that generation of bikes was the crankshaft oil seal, letting oil into the clutch housing - it didn't leave you by the side of the road but the bike had to be stripped to fix it - maybe 1 in 10 bikes or more had this issue.
 
Over 156.000 miles now.
2006 GSA.
Will it happen soon. 😱

80K on mine. I'm living on borrowed time :oops:. Scared to take it out now :rolleyes:

It’s pretty random, nothing to do with mileage.
I’ve seen bike with 30k miles that have dropped a valve, and look after a few bikes with 150K + miles that that have never given any problems..

IMG_2984.jpgIMG_2985.jpgIMG_2988.jpgIMG_2989.jpgIMG_2990.jpgIMG_2991.jpgIMG_2994.jpgIMG_2995.jpg

Even had a bike that dropped two valves
IMG_2987.jpgIMG_2986.jpg
 
Maybe but in the grand scheme of things how big is the problem in reality? - however I bet there are many more common failures on the GS of that generation. A very common fail on that generation of bikes was the crankshaft oil seal, letting oil into the clutch housing - it didn't leave you by the side of the road but the bike had to be stripped to fix it - maybe 1 in 10 bikes or more had this issue.

I’ve repaired more bikes with a dropped valve than leaking rear crank seals.,
What’s your repair ratio ?
 
I’ve repaired more bikes with a dropped valve than leaking rear crank seals.,
What’s your repair ratio ?
Fair enough - most of the leaking crank seals happened with new bikes in the first few months, so the vast majority (of which there was a lot) were done under warranty at the dealers, once fixed it didn't recur, so there will be very few old bikes with this problem showing up which explains why the independent mechanism don't see them.
 
I’ve repaired more bikes with a dropped valve than leaking rear crank seals.,
What’s your repair ratio ?

Thats why I have the HoofWakingBumbleCunt on Ignore!!

Keyboard warrior

"Knows Everything about Nuthin!" as We say over here
 
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It’s pretty random, nothing to do with mileage.
I’ve seen bike with 30k miles that have dropped a valve, and look after a few bikes with 150K + miles that that have never given any problems..
Or Mine at 11,986 and again on a rebuilt engine @23780 ish !!!

ALWAYS at the bottom of the sodium pocket where the friction weld is!
 


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