Cardan Shaft Failure

Only on paper only – not in reality

Once safely parked, I contacted my so-called insurance company. I had a comprehensive policy with them (MCE), and breakdown insurance was inclusive. All good? Not even close to being good!

Each time I rang them, it just auto hung-up the call! What a farce, and I haven’t even bothered complaining, as that would be futile too.

Edit – since this time the insurer went into administration – but they still called me to renew after this saga. So, I’d have paid an annual premium, that they’d provide (maybe) a month of, with no recourse or refund assumably. The sheer audacity was utterly incomprehensible. Wow!”.

Realising very quickly I was on my own, I made some calls to recovery companies. That too was also an experience. One company, a self-declared motorcycle specialist, who made out he didn’t know where I was, (despite being a local) and that he couldn’t get there (whilst he was googling the location)! He alleges to be a biker too… I very much doubt that.

I didn’t have the luxury of sitting around for three hours awaiting any “goodwill” as he put it. Some biker specialist he is.

Eventually I got in touch with a local recovery firm, and they were brilliant. Straight away they informed of a three hour wait, but I was grateful for a solution frankly; no more lies or deceit.

A gent who lives on the very edge of the village was incredibly helpful to me. Plus, he offered to let me park the bike in his garage overnight if necessary. Amongst other offers of help from him, his willingness to help was much appreciated.

He had also observed the seven bikers that rode straight past me. I have never ridden past anyone, EVER. If I got bitter, I would adopt that mentality myself; but I simply cannot subscribe to that mentality.

I was lying on the deck, hiding from the sunlight, when a local biker stopped to see if I was okay. He thought I was taking a breather due to the heat. But when I revealed I was waiting for a recovery truck, he offered to go and get me a drink, or anything else from the local shop. Faith in my fellow bikers restored. Cheers mate, I appreciated you stopping.

I was in a rut. I couldn’t take the jeans off of course. And, I had to walk about a half mile each way to the village shop to buy some drinks. Full clobber, carrying the helmet etc. My boots were not the best [now binned], and quickly gave me sore feet.

Being diabetic, I was really beginning to feel unwell. All the exertion and the heat etc. were taking their toll on me. By the time I got to the shop, I was feeling very unwell indeed. Anyway, I managed to get a drink and some sugar going on, so I was good again in no time. Just the residual headache.

That’s on me of course, for failing to manage my own health conditions correctly.

Luckily, the lovely lady in the Grafham village shop was a 50 year plus biker, along with her husband! She was lovely to me, and offered lots of help too. Even for calling her husband to run me back to the bike – an offer I could not accept of course.

Once back to the motorcycle, I managed to find some shaded ground to relax on whilst waiting for the recovery truck to rescue me. From this point onward my drama was no longer. I just wanted to get home, as my situation was a little precarious.

Again, the gent who was helping me before was still looking out for me, and for the GS too. I have every intention of buying him a bottle of wine for being a decent human. I will look him up when the bike is fixed.

I am not a mechanic obviously, but i am going to fix this if I can?

After much fretting and investigation, my diagnosis is that the cardan shaft and final drive are to blame.

When I dropped the the final drive down from the swing arm, and it was corrosion city in there.

At the gearbox end the cardan shaft was mint. But the other end at the final drive was not.

So much so, that it is very evident of neglect. There was no discernible evidence of preventative maintenance.

The final drive dropped off the splines of the drive shaft easily enough. However, this was actually the problem. The splines were in very poor condition, and corroded severely.

I had positioned the final drive so that I could see past the rubber boot, but still in place for the drive shaft to turn the final drive.

The noise I heard on the breakdown was very evident too. I gingerly put it into first gear, and the gearbox was fine, the clutch was fine too, but the final drive was protesting loudly.

Releasing the clutch fully was interesting. The final drive was turning, but not at the same speed as the other end of the driveshaft. I held the rear disc and the final drive stopped turning. Hence my diagnosis.

I managed to source a second-hand final drive from eBay for a reasonable amount, vs. the staggering cost of a new unit, or even a rebuild of my own unit. Neither option was financially viable.

With workshop prices averaging £60 +VAT per hour, plus the parts etc., I was not going to explore a rebuild.

I hoped there was no drive shaft damage. My guess is that there isn’t any damage. As I stated previously, I turned the engine off immediately, so hopefully there will be no damage.

I shall clean the whole swingarm area, and do my utmost to clear any signs of corrosion. Also, I will use the proper lubricants to seal the area from water ingress afterward – which will be a first judging by the state of things.

Both the final drive filler and drain plugs had been severely over-tightened. The drain plug had no O ring present either. Which explains why the plugs were ham-fisted tight, and semi-seized.

The BMW dealer did not service this item, as it’s not a routine item. The oil was old, dark and had water in it. No O ring on the drain plug also says that no workshop had ever attended to this.

The correct torque for both drain plugs is 20nm. But given how much muscle I needed to release both, it felt more like 100nm! I have bought two new stainless steel plugs for the replacement final drive from motoworks in Holmfirth.

From here onwards, I shall look after the transmission myself. It’s not difficult to do, and for the peace of mind, it was worth the learning curve to accomplish. I hope that after this fix, this issue doesn’t occur again – in fact in mean for it not to!

Sourced on eBay.

The replacement final drive arrived, and upon inspection was in much better condition than the original. Some minor exterior corrosion, but crucially, the splines and bearings are all in excellent condition. Also, it was from same year as my bike, same mileage too, which quietly amused me.

Whilst comparing the two final drives, I noticed that the original on my bike was missing the oil breather cap! Unbelievable. That would also explain why the oil that was in there was totally shot and contaminated with water. There’s a theme here – that this whole transmission had never been maintained.

Certainly no evidence anywhere, the splines or the shaft union having ever been cleaned or greased appropriately. Nor the rubber boots on the swingarm having any sealant or grease type application applied – as in no trace.

This was very telling too. I could see that the inside of the swingarm was really wet, and it was rust coloured water laying in a huge puddle at the bottom near the swingarm pivot. Obviously, this is from the condensation process that occurs naturally with use, but wow, what a mess.

Without too much drama I extricated the shaft from the swingarm, as there was no way I was going to leave that as is. It needed a thorough clean inside, so that was my first job.

There was no evidence of previous grease on the rubber boots at either end. The gearbox end was like new. That’s not an exaggeration either.

There was a profound reason why the final drive dropped so easily after the roadside failure. Given the level of corrosion evident it should have been nigh impossible to separate them without resorting to penetrating oil type products.

The reason this was not needed is of course is that the final drive splines were totally shot; as were the splines on the cardan shaft too. More expense.

Further investigation needed:

Out of curiosity I removed the shaft from the bike and tried the final drive end of both drives – off the bike – the duffer and the replacement final drive. One was an abject failure, and the other was no good either!

There was no tight fit on the replacement unit. It worked (kind of), I put the shaft back in, and put the replacement drive in place temporarily and started the engine for a quick test. It was working fine upon first impression.

I removed the cardan shaft again to clean and inspect further.

Out with the craft tool then, and clean the splines of the shaft at the final drive end. Shaft on the bench it became immediately apparent that the shaft was totally finished. The splines were badly rounded – completely ground-down and rounded very, very badly.

This failure was always going to happen. No ifs or buts. So check yours if you have BMW shaft drive as a matter of urgency and routine. Make it a part of your ownership. I know this topic is well documented, but it is for a reason. As I have found out to my cost.

I removed the knackered final drive from the bike, and I loosely fitted the replacement I had bought.

When I lined up the shaft with the replacement drive, there was lots and lots of play between them. Mine is a purely amateur opinion,; that this might have worked for a [very] short while, but failure would come very quickly indeed. Inevitable.

This is a risk I am not prepared to take – I can’t afford to take either.

So, I am on the hunt for a new (second-hand) cardan shaft. I did approach the eBay seller I got the final drive from, but he didn’t have any listed (despite asking me to search for one on his eBay page! Yes seriously). Anyway, he did make me an offer for a low miles shaft, but he wanted an eye watering £399 for it. Too rich for me.

So, I shall remain off the road until I can source a cardan shaft. I’m not unduly concerned by this, as like last year, this one has been a bit of a non event for myself and many other folks too of course.

Shaft found 22/08/2021

Lady luck was shining on me for once!

Needless to say that I have been searching very proactively for a replacement cardan shaft.

I was not expecting any joy; still reeling from the eye-watering £399 demand from a well known and respected second-hand BMW parts supplier.

I saw a really nice cardan shaft for £245 including postage on eBay.

It didn’t take too long to work out whether or not to buy the item! The specific listing had the ‘make an offer’ option, but I know from experience that I couldn’t wait to save perhaps ten pounds, and lose out whilst waiting for a response. So I just bought it.

A week or two to wait for delivery – the seller explained his reasons, which were fine by me; but it wasn’t mentioned that he was going to Spain for a fortnight when he listed it, but hey. What’s another week – which became two?! Mmm… Patience is a virtue!

This has added three extra weeks to the fix time though.

12-09-2021

Whilst I was stripping the bike to install the new (second-hand) part, I took some pictures to show the corrosion and the consequences thereof.

The shaft I bought on ebay has only covered 2000 miles, and is like a brand new part. The old one looks way better than it should, as I had cleaned it extensively as described above.

The images are quite shocking.

This is the final drive end of the drive shaft. This is the one that failed:

This is the replacement cardan shaft I sourced:

This drive shaft is like new – 2000 miles only

This has been a very expensive and annoying fix.

Sourcing the parts was especially exasperating. Varying levels of quality, and varying levels of honesty too. Greed featured too!

So, I now have five sets of washers, “O” rings, drive shaft circlips, and a large bottle of transmission oil for maintaining it myself in the future.

The appropriate grease for the splines and rubber boots are in hand to ensure no further repeat of this whole sorry tale.

Do check your own bike regularly. It can be a tricky job, but not especially difficult. If you have a decent set of tools and a good quality torque wrench, you could fix your own like I have.

Besides, there are lots of great videos available on YouTube to assist/instruct, plus the ubiquitous Haynes manual, which was a great help.

Test ride was good. I was really rather nervous after I started the bike on its centre stand and put it in first gear! It made some very peculiar noises, and I thought to myself “not again” – my bad for being stoopid!

My fears were unfounded though. I put it in gear on the side stand and all seemed well. That provoked a very tentative test ride, very locally too – just in case!

All was well. Gear changes were far less agricultural than before, and much smoother too.

Allowing for the visceral gear changes I’m used to, it was discernibly smoother.

Tomorrow I shall ride around the village for an hour or two!

Not venturing too far for now. I know I am being unduly wary, but you know what? I lost faith after that, trust even, but either way it will take time to be restored.

Back on the road finally…

Edit:

The year after this episode happened, BMW issued a recall for all affected LC models to receive a brand new cardan shaft. At 36,000 miles, and similar intervals thereafter. Mine was done along with a valve-check [major] service in February 2026.