F800GS Big End Replacement

stephen.stallebrass

stephen.stallebrass

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Ok so it was day one of my ride round Europe when my hazard and oil lights came on and I started getting a feint screeching noise... I finally get to a dealer in Elst, Netherlands after a 2-day delay because of the bank holiday where I'm told it's the 'big end''.

I'm not mechanically minded so what the hell is a 'big end'? I know it's some sort of bearing but what is the likely cause of this failure? Enlighten me, educate me please, I want to understand... I might not then go on a murderous rampage through Utrecht to vent my sorrow and frustration.

BMW Elst said it could be 600 Euros in labour alone. Is this accurate? Is there anybody here on the forum that can do it cheaper than BMW? Or does anyone knows someone that can do it cheaper than BMW? If not I wil have to suck it up and take it to BMW.

Any advice would be much appreciated.

xXx
 
The 'big end' is the bearing between the crankshaft and the con-rod, and as long as it's properly lubricated shouldn't really fail ... I'd suggest also looking at the oil circuit, or any other potential cause of failure (the classic one is running low on oil...)

If the bike's out of warranty then I'd not get anywhere close to a BMW dealer - they will charge extortionate amounts of money to do the job - if you have a modicum of mechanical ability then it's probably within your ability, but with respect ... the fact that you have to ask what a big-end is suggests that you dont. Once the bike's back home try to research for decent independent bike mechanics and have a word with them - you'll probably cut your labour bill in half that way. The cost of the bearings (plain metal 'shell' bearings ) will be tiny in comparison to the labour cost. But -as said - you'll need to identify the cause of the failure first.

Speaking of which - can anyone recall what happened about the countershaft bearing failure someone had a few months ago??

G
 
Cheers, I'm still none the wiser. :blast I really am retarded when it comes to mechanics, LOL! Off to Youtube to see if there is anything on big end failues... Apparently this is what a damaged big end looks like...

4476110854_776e12598f.jpg


BTW, any idea what causes it?

It was only serviced about 1K miles ago when I bought it. Its' been trouble free throughout. The oil is level and quality is fine. Going to try and find a non-BMW mechanic to do the work as it will definitely be cheaper but I fear I might have to suck it up if my old mechanic can't do it. I've contacted members of the Utrecht HUBB community in the vain hope that there is some Angel in the area that will be able to help me in some way. Fingers crossed.
 
stephen.stallebrass said:
Cheers, I'm still none the wiser. :blast I really am retarded when it comes to mechanics, LOL! Apparently this is what a damaged big end looks like...

4476110854_776e12598f.jpg


BTW, any idea what causes it?

It was only serviced about 1K miles ago when I bought it. Its' been trouble free throughout. The oil is level and quality is fine. Going to try and find a non-BMW mechanic to do the work as it will definitely be cheaper but I fear I might have to suck it up if my old mechanic can't do it. I've contacted members of the Utrecht HUBB community in the vain hope that there is some Angel in the area that will be able to help me in some way. Fingers crossed.
Click to expand...

Big-end failures are pretty rare these days, so you need to get to the bottom of the cause. Possible causes are:

  • oil starvation - caused by low oil level for example
  • oil pressure failure - caused by oil pump failure or a jammed oil pressure relief valve
  • oil failure - caused by poor oil quality (what oil were you using?) or overheating of the oil
  • contamination - could be anything
  • wear - probably exacerbated by historically inadequate maintenance regime

I'd be a little suspicious of a service just 1k miles before.

Effecting a decent repair on the engine is a top-end job for a decent home mechanic (+ many whippersnapping rock-apes that describe themselves as bike mechanics). Issues to consider:

  • Absolute cleanliness at all stages is an absolute! On reassembly, the engine components should be surgically clean.
  • Identifying root cause of failure
  • Checking for damage to the big-end pin
  • Checking the roundness of the big-end pin
  • Identifying the exact size of bearings you need. Even 'standard' bearings will come in a number of sizes.

You may do better looking for an engine from a wreck.

:hammer

Greg
 
Stupid Question

Never had a vehicle older than 10 years old so manufacturers warranty has never entered into my sphere of ownership. However, I just read on a forum that the BMW Factory warranty is 4 years and 50K miles... Is this correct?

Well mine is a 2008 with 31K miles? If so it sounds like my F800GS could be repaired under factory warranty? Do I need some sort of paperwork because I don't have anything pertaining to a warranty?
 
I'm not sure your warranty will be four years, mine was only two. Even so, I'd be looking to BMW for some measure of compensation if they did a service 1000 miles ago. The big end bearing should NOT fail.
 
Dave Ett said:
I'm not sure your warranty will be four years, mine was only two. Even so, I'd be looking to BMW for some measure of compensation if they did a service 1000 miles ago. The big end bearing should NOT fail.
Click to expand...

+1

A big end failure on a 31k mile bike that has been serviced to the book is absolute bollocks. I'd be riding it through the dealers window and parking it on the service desk :thumb2

The only reason for the failure would be oil starvation or poor quality original parts. If the bike is serviced by BMW and you can hold your head up and say it has never run low, then fight your corner. The least they could do is pay for the labour imho.
 
before anyone gets carried away with ideas of what happend lets wait untill its striped and then all will be revealed. JJH
 
Well that's a damn shame if it aint a 4 year, 50K miles BMW factory warranty as that's the last hope I harbour for getting it fixed here and continuing on with my ride in Europe. I'm clutching at straws.

From memory it's had all servicing done by BMW except for the last one which was done by Bike543 before it was sold to me. The last 1000K miles I've done in it have been trouble free. Contacting the AA tomorrow so we'll go from there... I reckon they'll be bringing me and the bike home!
 
Even if it is under warranty, if it's abroad, I think you have to pay then reclaim from bmw UK.

I think.
 
stephen.stallebrass said:
Well that's a damn shame if it aint a 4 year, 50K miles BMW factory warranty as that's the last hope I harbour for getting it fixed here and continuing on with my ride in Europe. I'm clutching at straws.

From memory it's had all servicing done by BMW except for the last one which was done by Bike543 before it was sold to me. The last 1000K miles I've done in it have been trouble free. Contacting the AA tomorrow so we'll go from there... I reckon they'll be bringing me and the bike home!
Click to expand...
How long have you got it? I think you are entilted to a 3 month warrenty on a bike from a dealer. EEC law and all that.JJH
 
stephen.stallebrass said:
Apparently this is what a damaged big end looks like...

4476110854_776e12598f.jpg
Click to expand...

Is this your actual big end cap? It's not a great pic, but the bearing shell looks ok to me. However, the cap has some unusual scoring on it.

Big end bearing failure (any bearing come to that) from a Rotax engine, or indeed any modern engine is really rare these days.

I'd have thought that BMW might want a look at this.
 
v8legend said:
Is this your actual big end cap? It's not a great pic, but the bearing shell looks ok to me. However, the cap has some unusual scoring on it.

Big end bearing failure (any bearing come to that) from a Rotax engine, or indeed any modern engine is really rare these days.

I'd have thought that BMW might want a look at this.
Click to expand...

No, just one I saw on Flickr when I was trying to find out what a big end failure was all about...
 
On my 800GS I had the oil light come on when I was in heavy queuing traffic but I killed the engine immediately and let it cool down, I later found it was the fan that was blocked with crud check if the cooling fan is spinning OK, my engine didn't appear to suffer any ill effects though just a thought
 
With the big end gone, Your engine is now toast unless:

a, your have excellent mech skills
b, you have deep pockets, for BuWM to fix it!
c, let a indie repair it, But you need to choose one,With a good reputation.

The simple answer is to find a running engine from a scrapper,
Best of luck:aidan
 
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