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Mark – 2015 R1200R-LC Exclusive
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Discussion Starter #1
Fork oil change

OK, I've only just done my 10,000 km service, but the suspense is killing me. I'm very confident with meeting the service requirements for my LC but at 30,000 km I'm due to change the fork oil and the BMW manual specifies a complex tool to compress the fork springs.

Anyone willing to share the technique specified in the Haynes manual for disassembly/re-assembly of each fork leg? The books aren't yet available here (to my knowledge) and OS freight is prohibitive.
 

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OK, I've only just done my 10,000 km service, but the suspense is killing me. I'm very confident with meeting the service requirements for my LC but at 30,000 km I'm due to change the fork oil and the BMW manual specifies a complex tool to compress the fork springs.

Anyone willing to share the technique specified in the Haynes manual for disassembly/re-assembly of each fork leg? The books aren't yet available here (to my knowledge) and OS freight is prohibitive.
I can't help with Haynes (as yet) but RaceTech sell a compressor for upside down forks which looks like it may well do the job - no idea on price though.
I also wonder whether it's possible to do an oil change by partially draining the forks by loosening the top caps and inverting, then repeatedly flushing them with ATF or similar, like power steering on a car. Might end up as half a job being worse than none though.
On a similar note, I occasionally look at those beautifully finished fork tops and wonder what on earth you would use to unscrew them with that wouldn't chew them up - an acetal lined socket possibly?
 

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Mark – 2015 R1200R-LC Exclusive
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Discussion Starter #3
Thanks Sprigger. The flush-style method also crossed my mind, but setting the oil level becomes problematic.

If you had a precision scale, I suppose you could weight each prior to draining, then fill until they weigh the same.
 

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Mark – 2015 R1200R-LC Exclusive
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Discussion Starter #4
30,000 km is fast approaching, so this topic arises again.

The Haynes manual has been available for a while and takes a lot of the technicality out of the procedure, with just a couple of simple home-made tools required to be fabricated in place of the complex BMW special tool. So it isn't as scary as first thought when you view the BMW manual, even the ESA version.

One thing not mentioned in the Haynes manual is the caution required when removing the legs from the bike to avoid scratching. A work colleague picked up his S1000RR from a service some years ago to find zig-zag scratches on the gold forks.

I note that the Haynes manual doesn't bother to remove the dampers, just pumping them to remove the old oil and letting stand upside down for a while to allow drainage. Once you are at that stage of disassembly, though, removing the dampers isn't much extra effort (just need a replacement washer for each leg).

One puzzling thing, though, is that the BMW manual specifies 7.5 W oil, whereas the Haynes manual states 10 W across all models. I've already bought 10 W oil as part of an online purchase, so am tempted to go with that. My preference is for heavier rather than lighter damping and it seems the damping has softened a little since new anyway - if I don't like it, it isn't too much effort to change it later.

Has anyone done a fork oil change yet, and what spec did you use?
 

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Mark – 2015 R1200R-LC Exclusive
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Discussion Starter #5
BTW, a good mate recommends kerosene for flushing away old oil and debris. To give you an understanding of his credibility, he keeps a Benelli Tre on the road, and is on a first name basis with the Benelli engineers, having sorted a lot of teething problems for the bike on their behalf. (Don't you just love passionate Italian engineers ...)

He advises that kerosene is used to thin oil for testing. It doesn't have the anti foaming agents that fork oil needs, but it is just a higher fraction from the same base. Being such a low viscosity it can thin and carry away debris easily, and drain to within a few drops.
 

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A dealer carried out my fork oil change at 18000mi and I've no idea what went in there - presumably BMW recommended oil but the bike does feels firmer again - maybe just placebo effect. I used the dealer to keep up the warranty.
Ive just changed fork oil on an old Triumph Sprint and used cheapo 5W fork oil as a flushing agent to avoid disassembling the legs fully - in the past I've used ATF to flush which is even cheaper .
I've used ATF as fork oil in the past as well - I seem to remember it's around 12 - 15W
 

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I would go for the 7.5 weight. Maybe 10 would actually be ok but if it doesn't work out you have to pull the whole front end apart again. I can't imagine why Haynes would contradict what BMW specify, do they know more than the people that built the bike? I'm not sure on the maths of oil viscosity but wouldn't 10weight be 25% heavier than 7.5?
 

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Mark – 2015 R1200R-LC Exclusive
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Discussion Starter #8 (Edited)
The product data sheet for Castrol fork oil (the oil I have) makes an interesting observation - "Fork oils with the same grading; e.g. 5, 10, etc., may be significantly different in viscosity. For example, Castrol Fork Oil 5 is essentially the same viscosity as some products marketed as 2.5 grade oils."

So I might just go with the 10 W and see what it feels like. Who knows, it may be the same viscosity as BMW 7.5 W - at least I'll know for the future. Besides, Castrol only make fork oil in 5, 10 and 15 W grades, and it's my brand of choice.

There's an interesting calculator for mixing oils (of the same formulation/manufacturer) on this site. This would indicate a 60:40 mix of 10 and 7.5 W respectively.

On the subject of ATF, I've used Dexron ATF before as a flushing agent in my F800 forks (and it was the specified fork oil for my Ducati SS900). I intended to do the same with the R, but my colleague assures me that kerosene is safe to use, and being thinner, will flush better.
 

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Mark – 2015 R1200R-LC Exclusive
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Discussion Starter #9
Correction:
"There's an interesting calculator for mixing oils (of the same formulation/manufacturer) on this site. This would indicate a 60:40 mix of 10 and 5 W respectively."
 

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The product data sheet for Castrol fork oil (the oil I have) makes an interesting observation - "Fork oils with the same grading; e.g. 5, 10, etc., may be significantly different in viscosity. For example, Castrol Fork Oil 5 is essentially the same viscosity as some products marketed as 2.5 grade oils."

So I might just go with the 10 W and see what it feels like. Who knows, it may be the same viscosity as BMW 7.5 W - at least I'll know for the future. Besides, Castrol only make fork oil in 5, 10 and 15 W grades, and it's my brand of choice.

There's an interesting calculator for mixing oils (of the same formulation/manufacturer) on this site. This would indicate a 60:40 mix of 10 and 7.5 W respectively.
If you put in 10W and know the quantity, and it's too harsh, then maybe just slacken off the fork caps and siphon off the relevant volume of fluid and replace with lighter. I played around like this with a Tiger after I'd "Race-Tech d" the forks and it was less painful than pulling the forks for each tweak.
Useful tip to use kerosine/paraffin (uk) thanks
 

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Maybe it's a stupid question but I really don't know, so I will ask :)

Is fork oil change scheduled at 30.000km by BMW maintenance plan, or you are changing it simply because you want to try different oil ?
My dealer never mentioned that fork oil needs to be replaced at some mileage, so that's the reason why I ask
 

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The main dealer I took mine to for 18000 mile service, which I guess is 30000km equivalent, had it down as BMW maintenance plan - (I usually change fork oil at 12000mi by which time it's generally pretty much degraded ).
 

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Mark – 2015 R1200R-LC Exclusive
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Discussion Starter #13
Fork oil change is part of the scheduled maintenance - every 30,000 km, although as others have noted, it usually looks pretty black by then, so shorter intervals wouldn't be a bad idea if you can be bothered.
 

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The variation in fork oil weight, or viscosity can be significantly different between brands or even between product ranges within brands. In an effort to get back to an OEM-like starting point in the past I've found this chart particularly useful: https://transmoto.com.au/comparative-oil-weights-table/
 
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Mark – 2015 R1200R-LC Exclusive
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Discussion Starter #15
Would have been nice for BMW to specify the fork oil in cSt at 40/100 C rather than the sloppy 7.5 SAE.

In any case, I'll see how the Castrol 10 feels, and work from there. At least with the cSt figures, I have something to work with.
 

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Would have been nice for BMW to specify the fork oil in cSt at 40/100 C rather than the sloppy 7.5 SAE.

In any case, I'll see how the Castrol 10 feels, and work from there. At least with the cSt figures, I have something to work with.
Is it possible to do the standard, quick oil change without fully disassembling the forks and removing spring/damper ?
By this I mean flipping the forks upside down to drain the old oil, pump it few times then drain again ? I know that this method will not get all the old oil out, but it should get at least 90% of it. That's how I did it on my old bikes.
When it comes to fork oil change, I would like to avoid disassembling the forks, especially because of the ESA mechanism
 

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Is it possible to do the standard, quick oil change without fully disassembling the forks and removing spring/damper ?
By this I mean flipping the forks upside down to drain the old oil, pump it few times then drain again ? I know that this method will not get all the old oil out, but it should get at least 90% of it. That's how I did it on my old bikes.
When it comes to fork oil change, I would like to avoid disassembling the forks, especially because of the ESA mechanism
Esso, see posts #2 & 3
 

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Mark – 2015 R1200R-LC Exclusive
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Discussion Starter #18 (Edited)
I'll let you know of my experiences when I get to doing it, and post some photos if relevant. As noted above, the Haynes manual takes some of the mystery and fear out of it, but colour photos and a bit of personal experience make all the difference, I reckon.

BTW, why does Haynes print its manuals on 'toilet paper'? Surely it wouldn't be much more expensive to use quality paper; a whole ream of 80 gsm office paper is only a few dollars.
 

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BTW, why does Haynes print its manuals on 'toilet paper'? Surely it wouldn't be much more expensive to use quality paper; a whole ream of 80 gsm office paper is only a few dollars.
:grin2: Good one! And an excellent question. I think their pictures would be a bit clearer on better quality paper.
 
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Mark – 2015 R1200R-LC Exclusive
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Discussion Starter #20
LC ESA Fork Oil Change

I’d never changed oil in USD forks before, and that ominous black lead entering the LH fork cap looked particularly daunting – what kind of sensitive electrickery might lurk beneath. Looking at the BMW manual didn’t assuage my concerns at all, noting though that it is written for an audience of factory trained, white coated technicians working in a sterile environment with a wall full of special tools. The Haynes manual makes the job look more manageable, so I bought a litre of fork oil, prepared my tools, and off I went.

All went pretty smoothly, albeit slowly, as I am meticulous in these matters, and as noted above, this was a first for me. In terms of the result, I followed the Haynes specification and bought 10W oil (in my case, Castrol), finding later that the BMW manual specifies 7.5W. Fork oil is a black art – even the Castrol label acknowledges that each manufacturer specifies their oil differently, so oils with the same rating on the label may be quite different in performance.

Initially on riding, it was hard to discern the difference with the new oil. Over time, though, I have concluded that the front end is damped a little more stiffly now. There’s a less pronounced difference between Road and Dynamic suspension modes. I tend to use Dynamic mode less now, as in Road mode the front end feels a little more controlled and gone is that little tendency for the front to feel as if it is falling away on vigorous tip-in as the suspension settles. It may also be my imagination, but I think I can feel the road surface (ripples, coarse paving etc) a little more. I don’t mind the extra firmness, but those who value comfort more than taut handling may like to seek out a lighter oil for their change.

In addition to the usual tools required for working on these bikes (Torx bits etc) you will need a 32 mm spanner to loosen/tighten the fork caps. The torque required is pretty low (20 Nm), so a tight fitting shifter (i.e. where the jaws are perfectly parallel) can do the job (adjustable wrench for you ‘Mericans). My big shifter went walkabout somehow so I ended up buying a combination spanner, and now have what must be the biggest, shiniest spanner in the suburb. A single layer of masking tape should be placed around the fork caps to prevent marking from your spanner/shifter.

A large shifter would also be better than the multi-grips I used for the internal ring that tightens up against the LH fork cap, but is not critical as this is an internal part so minor marking, if it happens, is not of concern. I forgot to measure the required jaw width, but probably around 36 mm.

I made my ‘holding tool’ as specified in the Haynes manual from a couple of large L brackets, cut, drilled and tapped to suit, then screwed together, with M8 screws to engage the holes in the plastic spacer tube. Pushing down on the tool compresses the fork spring so you can (with your third hand) place a slotted washer above the tube to hold in place. The Haynes manual doesn’t say so, but it’s pretty much a two-person job to compress the RH fork spring THEN insert the holding washer. The furry newsprint photo hints at this requirement. I had no additional hands available so I had to improvise (family members enter the garage only to access the car or dump things for storage). I used a ‘ladder strap’ from one side of the tool, through the bottom of the forks, then back up to the other side of the tool. With this knowledge, I would have made the holding tool wider, the technique being to tilt the tool so that the side with the screwdriver is as low as practicable, nip up the holding strap, then push down on the other side to bring the tool level whilst tightening the strap. The screwdriver provided a roller for the strap to move over as the tool pivots while the strap is being tightened.

A further tip for the single-handed mechanic is to ensure you have a means of firmly holding the fork upright. I used a household step and then some webbing straps to lash the fork in position, with some high density foam between the fork and the step handle.

As noted in the Haynes manual, a short piece of garden hose is needed to hold the damper rod in the fully extended position during reassembly of the RH fork.

A little piece of PVC hose will help adjust the fork oil levels when you get to that stage. Because the required amount is a tad less than a litre, I was happy to siphon a little excess back into the bottle rather than to waste, just to ensure I didn’t run short.

During the disassembly process, keep meticulous note of which way things go – both in sequence and orientation (easy to get a spacer or ring upside down). On the RH fork a plate is specified at the base of the internals, under the lower washer – oddly, either mine doesn’t have one, or it stayed in place. The sleeve between the fork outer and inner did come out though – no mention is made in the Haynes manual, so just be aware of it.

I suggest servicing the forks one at a time and doing the LH fork first. Once you have fully disconnected the electrical lead (which stays attached to the fork) then tie back the ‘bars to the rear of the bike so they don’t flop around.

Actually, disconnecting the electrical lead was the one area that stumped me for a while as I couldn’t figure out what was holding it onto the mount that attaches it to the LHS of the coolant reservoir. I eventually prised the whole thing off so that I could find the little tab that releases the female connector (which is attached to the LH fork lead) from the mount. The technique is to first separate the connector by removing the lower (male) part after pressing down on the outer tab. Then get a small screwdriver in behind the open mouth of the female connector and push the little tab towards the front of the bike. The connector will then slide upwards off its mount.

Before starting work, clean any grime from the forks so the forks are not scratched by grit when removing. Make a note of the position of the forks and fork caps so that they go back exactly the same (once removed, you will see marks on the forks at the triple clamp openings). I used a screwdriver blade on the bottom clamp opening to prise it a little to ease the fork out/in – again, to avoid any prospect of marking the forks. Some years ago I recall a mate had his S1000RR forks serviced at a dealer I won’t name and they came back with zig-zag scratches on them from the removal process – to be avoided.

I used a scrap of aluminium I had at hand for the slotted holding washer. This was not optimum as the paint flaked off a bit under tension. However, once I perfected the hold-down strap technique, the washer was almost superfluous anyway; it wasn’t under tension during reassembly, so there was no risk of paint flakes falling into the oil.

When removing the springs from the forks, do so slowly so that the oil drains off pretty well as you lift them.

I flushed my forks with kerosene (paraffin for the Poms) for good measure. It drains off really well (better than the fork oil) and an engineer friend assures me it comes from the same oil stock anyway, so a few residual drops are not going to impact adversely.

The Haynes manual doesn’t say so, but rather than just let the new the fork oil stand for a while to allow bubbles to escape (they seem not to of their own accord …) I pumped the LH damper rod slowly until no further bubbles emerged (there’s a lot of resistance) and then re-measured the oil level. The RH damper rod is easier to pump.

I also scribbled out a list of dot points of all the tasks before starting – I find this easier to follow in the workshop than the narrative of the Haynes manual, having already familiarised myself with the latter. I’ll try to find time to type it up for posting here.

Overall, the task isn’t as hard as might be imagined. I’ve attached a few iPhone photos to help illustrate the above, although in the heat the phone kept shutting down, so the one showing the strap is a one-handed iPad photo – hence the blur.

Non-ESA forks are pretty much the same technique as the RH fork, buy oil level specs are different.

Some key torque values:
Bottom yoke bolts 19 Nm (tighten progressively)
Fork caps 20Nm
Top yoke 19 Nm
Brake calipers 38 Nm
Axle 50 Nm
Axle clamp bolts 19 Nm (tighten progressively) 19 Nm
 

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