R1100RT Cam Timing Issue - Advice Please

[GrayFox]

Ride a 1998 R1100RT. Its covered 117,099 miles, not all mine. In almost daily use year round and has never missed a beat until the other day when out on a run without warning there was a nasty metallic knocking emanating predominantly from the left hand cylinder. Pulled over with clutch in immediately and turned off the engine - got a breakdown truck home. Initial thought was that the big ends had gone but when I opened it up I found that the cam timing must have jumped. There is no damage to the valves or the pistons but I detected a small mark on the crown of the piston which would suggest that the cam timing may have slipped. What would have caused this? Could the vertical chain have broken or slipped and why? Obviously I am also de-coking it (a fine opportunity really as I have never stripped it before) and I will need to replace gaskets and maybe some chains, tensioners and so on. Don't want to skimp on this but don't want to spend money unnecessarily or in the wrong direction. If anyone else has has any advice I would appreciate their opinions. Have also posted this in another BMW forum. Need all the help I can get! Thanks.

[OoPEZoO]

The only thing that pops into my head is that you might have broken off part of the timing chain guide. I've heard of it happening on a few high mileage motors, but have never seen it first hand. That could cause a lot of slop in the timing chain and allow it to jump teeth.

 

Don't hold me to this, but I believe I read that the engine case must be split in order to replace the timing chain guides.

 

Have you pulled the heads, or just the valve covers?

[GrayFox]

Hi Keith

Good plausible suggestion but I have had a good look with my new super-torch and cannot see signs of a broken tensioner blade. Splitting the engine is not really something I wanted have to do, of course - though have read somewhere they can be changed without splitting the engine. Will take another look at it in the morning and try to check that tensioner again.

I am having real trouble getting the front cover plate off in order to check the front primary drive chain timing. The manual says it should come off but I can't get it clear of the wishbone. Do you know of any tricks to do this? Does it have to be done with the bike on or off the stand?

Thanks for your time. Nice duck!

Derek

[dirtrider]

Hi Derek

 

You will probably have to remove or at least move the alternator to get that front cover to clear the front control arm.

 

Do you still have the right cylinder head on the engine? If so turn the engine to TDC compression on the right bank then see if the cam sprocket arrow points straight out. If it does your front cam chain is probably still in time. If the arrow point other than straight out you have a good possibility of a front chain timing issue.

 

 

 

[AndyS]

Morning Derek, Glad you found your way over to the site. You'll find a host of good stuff here.

It looks as though you have some busy evenings ahead of you.

 

Andy

[GrayFox]

Hi, Many thanks for your time. Today I have managed to remove the alternator but still have the adjuster bolt on the left hand side of the alternator carrier seized in position. In all probability these have never been touched since the bike was built. Was interrupted by an unexpected visitor and will return to it tomorrow morning to try to get the front cover off.

The RH side has been checked and the arrow points outward as it should but the left hand side showed the arrow askew, maybe by just one or two teeth.

Regards, Derek

[dirtrider]

Hi Derek

 

If the right hand arrow points straight out on r/h side TDC compression that side is more than likely still in time. Sounds like your problem is with the left hand side cam timing between the auxiliary shaft to the cam sprocket.

Look carefully at the chain guides “both top and bottom” for signs of the tip or ends of the guide being broken off. If either cam chain guide is broken that is a sure sign of either a slapping around chain or the engine was rotated backwards with a loose chain tensioner.

 

[GrayFox]

Taken a day off today. Bought another inspection mirror and will take a fresh look tomorrow. On previous inspection there was no sign of any damage to the guides but on your advice I will take an even closer look. Watch this space!

[Trullion]

The arrows on the cam may sometimes appear to be a tooth out i.e. not quite horizontal. The bike worked on in the Haynes workshop manual exhibited this. There may therefore be nothing wrong with the l/h cam position.

[GrayFox]

I am now thinking this may be the case. A lot of people have said they have never heard of this happening. I still face a struggle to remove the bolt to get the cover off but will get there. Maybe just rebuild with new gaskets, double check everything, turn over by hand and make sure it all aligns and hope it all works. Have to be careful cleaning those previously inaccessible places, don't want bits dropping into the engine. Will post up progress.

[dirtrider]

Hi Gray Fox

 

You better hope those sprocket timing arrows are correct as you will need to use them to retime the cams at reassembly time.

The inner arrow should point directly at a sprocket tooth, the outer arrow will point a place between the tooth tips. The inner arrows at TDC compression on that side should point to the whiteness mark on the timing gear carrier.

 

In any case the SURE way to see what you have for cam timing is to remove the sprocket retention bolts to expose the locating pin.

With the right hand side on TDC compression the locating pin should be at the very bottom “straight down”

With the left hand side on TDC compression the locating pin should be at the very top “straight up”

 

[AndyS]

Can't say fairer than that. The bike must be torn down to a state you can do the above checks.

[GrayFox]

Thanks for the advice. Will follow it to the letter when reassembling the bike. Today rang dealers and ordered parts. Whilst waiting for them to arrive plenty of cleaning and odd things to do. Will post up some photos and list of parts used when the bike is running sweet again.

[GrayFox]

It sure is! Sadly many bits have had to come off and the bike looks a sorry sight. Decided to take the zen approach and use it as a real chance to ensure many more years of use. Still no luck with the bolt mentioned above. Any ideas welcome.

[notacop]

Honestly, at 117K miles, it's not just the noisy parts that are worn and will need some dedication in the future. Like the Trans, rear end and etc.

My 2001 RTP wasn't running like it was dying at 120K miles but the dealer that checked it for trade in gave me a ling list of what they thought was wrong with the bike. I got $1000 trade on it. And glad of it.

Not that you couldn't get many more miles out of the bike but at what price?

That new 1200RT has cruise control and heated seat. It's lighter than your bike and there are no worn parts.

Oh, that bolt you can't get loose yet, that's another $700 before your done.

[GrayFox]

Hi Notacop. Well I can understand what you say but for a fraction of the price of that new 1200 I think I can get my bike good for a few more years. There is a lot of complex electronic wizardry on a new bike - all waiting to go wrong. I have just sold my modern car and bought a 1969 Triumph car for much the same reason - I can fix it. That bolt is turning now but still not wanting to come out but it will someday soon, may have to try witchcraft.

[gbr300]

I admire your persistence. I wonder if James Sherlock can help as I notice he is not too far away from where you are.

I expect you already know about him. I think that your bike will do another 100,000 after your TLC and that repairing it is worth while.

[AndyS]

So, GreyFox, how far are you pulling your bike apart?

The reason for the question is that if you are going really deep, maybe now is the time to consider breaking the gearbox off of the engine. Maybe time to re lube the splines, check the state of the input shaft and if required replace the clutch, cluthc bearing and pressure plate. Also to check the condition of the starter ring around the outside of the flywheel.

 

Andy

[GrayFox]

Hi

Thanks for the James Sherlock reminder. Needing to replace rocker arms as threads have gone. Managed to get the bolts out but fear new bolts alone will not be enough. They seem to sell the arm without the bolts which are another £9+ each!

When you strip an engine you discover how heavy handed previous owners or their mechanics have been!

Brake failure on the Triumph means I have spent the day fixing that instead.

Derek

[GrayFox]

If time and cash was freely available I would like to do as you say - breaking the gearbox off of the engine. time to re lube the splines, check the state of the input shaft replace the clutch, cluthc bearing and pressure plate.check the condition of the starter ring around the outside of the flywheel........... an endless list.

Unfortunately I can't go to such lengths but will be doing as much as is practical and get back on the road soon. The clutch was replaced at c 50k. If it aint broke dont fix it.

[GrayFox]

Got that bolt out today at last, just pure persistence and a bit of chain lube and half a can of WD40. I managed to get it out without destroying it and I have reconditioned it and its now back in place. Made good progress today. After getting that bolt off I was able to remove the cover at last and could clearly see that the timing marks are all in order. I rebuilt the front end after giving it a really good clean up, re-installed the alternator and all cables and put the electronics back. Now awaiting gaskets and spares to be delivered before reassembling the left hand side and starting to strip the right side for a clean and de-coke.

The only thing I have found which may have caused the initial problem is a very small piece of grit near the cam follower which could have got in when I topped up the oil before the run - it was very windy at the time.

[GrayFox]

The new parts were delayed - understaffed south west main dealership took order and card details but "forgot" to process it until we rang to find out why it was taking so long! I have rebuilt the left hand side and proceeded to strip the right hand side. EUREKA!!!!!!!!!!!!!!!! Have discovered that the right hand cam had started to disintegrate - cam lobe surface breaking up and the particles had been flying around, possibly getting jammed between push rod and cam followers. A mercy it did not do more damage. The cam is beyond redemption or so I have been told today by local engineering specialist. Have ordered a replacement part from James Sherlock of South Molton at £60. While I wait have done a decoke, welded and polished the exhaust and cleaned up the tupperware - it sure aint pretty without it.

[AndyS]

Wow, that's unusual. Anyhow glad you have found it and hopefully everything will be tickety-boo.

 

Andy

[4wheeldog]

I'll bet your oil filter has an interesting tale to tell......It might be worth doing an oil analysis after a couple of quick oil changes.

[GrayFox]

Very pleased to say that the bike is up and running and is off for its MOT tomorrow. It started up first turn last night and ran a bit lumpy but after checking,d resetting valve clearances and retorquing everything on both cylinders today it was sounding good. Road test tomorrow. Seems to have taken a long time since the initial breakdown a month ago but much of that was taken up pondering causes and waiting for parts. Many thanks to all who have taken the time to advise and encourage along the way. Stay safe. Derek

[oldyam]

Hi Derek

 

Good to hear

 

Enjoy the miles tomorrow, here's hoping for good weather