1200 Dropped valve, doesn't matter if its Right or left cylinder

DrFarkoff

DrFarkoff

Grumpy Ole Git!!!
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So As you may have read my inherited Mk1 R1200GS has yet again had a valve head drop off and wreak havoc :mad:

A LOT of havoc this time even as far as to bend the conrod .. :eek:

its the second time! The two occurrences are polar opposites in the way that it happened One at Low rpm and just at 3 bars

Second time I hit the revlimiter missing a gear and going back in the same gear as best I can remember It was a bit of a Blur!

Both times it was a catastrophic failure, but this time somewhat more catastrophic :blast:blast

Thankful to still be here really, as the piston jammed the remainder of the valve against the cylinder head and locked the crank!

I am Soooooooo glad I kept the clutch pulled in! A locked back wheel at 65mph :green gri whilst getting an overtake done cleanly and quickly Could have been very "sore" in the end :eek:

SO Dropped Valves

I "believe that the usual mileage for a dropped valve is sub 25,000 miles??

Has anyone any experience of the failure above that mileage?

I am thinking of buying a high mileage engine rather than a pretty low miles one ready for it to happen again :(

Sort of thinking if it hasn;t fallen off in 65,000 miles then it probably won't?
 
Mmm this is interesting... Mine had a re-build at 11k when they fitted two new rods and pistons... No idea why and was done by BMW... Wonder if this was the reason.... Sounds like it happens a lot... Any age of bike??
 
Bad luck

How reliable is the rev limiter? But to be fair a missed gear at high revs closed throttle is likely to spin the engine beyond the limiter.

Posh petrol puts less heat down the exhaust gives the valves an easier time.

If the engine locked up there is likely to be bottom end damage. At the very least, the big end shells will be flatted but conrods are probably toast anyway. A replacement engine does make sense. Fit new valves anyway.

A remap that solves the weak midrange would make high revving less necessary. It also solves the ultra weak fuel mixture at low throttle openings.

I read somewhere the 1150 should have new valves as a service item. Can’t find the item so might be making it up.

This suggests new valves at 40K miles which puts my 1200 (70K) well into danger territory.
http://www.moorespeed.co.uk/bmw-engine

Found this while looking

https://youtu.be/hpT-u1KgoZs
 
A mate had an '05 iirc (yellow piece of shit) drop a valve on its final ride during his ownership to Bahnstormers for trade-in. Just cruising up the A32 and bang with no warning. Lucky for him that they recovered it and honoured the part-ex deal.
 
Bendy toy said:
I read somewhere the 1150 should have new valves as a service item. Can’t find the item so might be making it up.

This suggests new valves at 40K miles which puts my 1200 (70K) well into danger territory.
http://www.moorespeed.co.uk/bmw-engine
Click to expand...


Thats for R100 Bendy they had solid two piece friction welded valves and the heads used to fall off at 40K miles

4 valve engines have much smaller mass of valve etc etc

I know of a quite a few 1150 over 100K miles and never had a spanner at the engine apart from servicing

|I am thinking now it is MUCH more important to check the ovality of the valve guide so at least the valve seats sqaurely and doesn't build oscillations to fracture that friction weld
 
DrFarkoff said:
Thats for R100 Bendy they had solid two piece friction welded valves and the heads used to fall off at 40K miles
Click to expand...

Ah Yes. :eek: The perils of smartphones and crap eyes.

Checking 1200 valve guides for wear isn't an easy task and if they are worn it will need new valves as well.
 
Bendy toy said:
You are such a troll. Read post 5.

Quote: I read somewhere the 1150 should have new valves as a service item. Can’t find the item so might be making it up.
Click to expand...

So why mention something that is wholly incorrect......at all

A lot of what you write on here about engineering is fiction

Best one was .....drilling out a stuck GS gearbox filler cap

Stick to chiropractors
 
JohnnyBoxer said:
So why mention something that is wholly incorrect......at all

A lot of what you write on here about engineering is fiction

Best one was .....drilling out a stuck GS gearbox filler cap

Stick to chiropractors
Click to expand...

amen to that.
 
Unfortunate.

Not speaking from experience.
I suspect the failures are just a matter of luck.
55k on mine, hits the limiter on every ride, and you know my attitude to maintenance.
Myke
 
I've had 1200 with valves dropped at 18k up to 75K.
No pattern it seems totally random.

But i do see more 1200 bikes with dropped valves than 1150 models.
And out of the 1150 models the overwhelming winner is the RT (especially the silver coloured bikes :D).
Maybe due to the full fairing causing the engine to run hotter.
 
i rebuilt one with a dropped valve.total carnage. but i had the software updated and didnt hear anymore of it.
 
Nomad biker said:
but i had the software updated and didn't hear anymore of it.
Click to expand...

So did I Pauly and I put 15,620 miles more on it until this happened

So the left side has 27,600 ish miles on it and I've never had an issue with valve clearances on either side

I did fit a booster plug or what ever gadget that was and the air temp was down at -40 so she was slightly sooty (slightly rich but not over rich) and NOT white at all

It must be a "resonance" thing about these boxers
 
DrFarkoff said:
So did I Pauly and I put 15,620 miles more on it until this happened

So the left side has 27,600 ish miles on it and I've never had an issue with valve clearances on either side

I did fit a booster plug or what ever gadget that was and the air temp was down at -40 so she was slightly sooty (slightly rich but not over rich) and NOT white at all

It must be a "resonance" thing about these boxers
Click to expand...

fitting a booster plug might have been the undoing of it. you cant beat a rolling road remap. a one fits all solution isnt always the best route.
 
When you can;t afford a rolling road remap ???

Its the best compromise that I could make at that time

What is sad is that I had a Wunderlich system sitting waiting to go on to her!

If it increased fuelling to offset the perceived cold atmosphere it did a right good job for nearly 16,000 miles

@£300 for a postal generic map I am sorry I don;t see it as value for money, when its only another £50 for rolling road time??

Besides What influence would a map have other than to correct fuelling I struggle just at the minute as to how that should that reduce the risk of dropping a valve ? Of which 7 or 8 out of 10 of those dropped valves are right hand side exhaust valves ??? :eek:

Nomad biker said:
fitting a booster plug might have been the undoing of it. you cant beat a rolling road remap. a one fits all solution isnt always the best route.
Click to expand...
 
DrFarkoff said:
When you can;t afford a rolling road remap ???

Its the best compromise that I could make at that time

What is sad is that I had a Wunderlich system sitting waiting to go on to her!

If it increased fuelling to offset the perceived cold atmosphere it did a right good job for nearly 16,000 miles

@£300 for a postal generic map I am sorry I don;t see it as value for money, when its only another £50 for rolling road time??

Besides What influence would a map have other than to correct fuelling I struggle just at the minute as to how that should that reduce the risk of dropping a valve ?
Click to expand...

I think the problem with the dropping valves is excess temperature, either generated by an incorrect mixture, or the valve being too tight and losing duration of valve seat contact time, thereby causing the valve to overheat and fail. The emissions trail is sometimes the culprit as the bike is run too close to get it through the emissions goal. also running unleaded versus super unleaded would also contribute to this. These after market gismos out of the packet are just fooling the ecu into doing something it shouldnt by lying to it.Also an outside influence could be lack of head cooling ,poor oil, and maybe fairings that are blocking the air flow and making it run hot.
 
Nippy Normans supply Touratech, Wunderlich, Desert Fox and many other makes of accessories.
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