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Does anyone have the official BMW fork oil volume and air gap for a 2016 RS with ESA. I have not been able to find the OEM service manual, so I am using the Haynes one.
Their volume spec for the ESA fork is about double (304ml) of what I drained from the ESA fork (155ml). The air gap they spec is 65mm. Adding fork oil to get
a 65mm air gap takes about 160ml, which corresponds to what I was able to drain. So Im guessing that the Haynes volume spec is wrong.But before I reassemble the fork
I wanted to canvass the forum to establish what is listed as a spec/procedure in the OEM manual. Thanks.
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I have found the same information as you, 304 ml Sae 7.5 oil with 65mm oil level to top of fork tube with the rod fully compressed with no spring or spacer.
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01-27-2023, 09:15 AM
(This post was last modified: 01-27-2023, 09:18 AM by Lee.)
The BMW DVD shows
Left leg 304 ml and 65 mm gap
Right leg 682 ml and 82 mm gap
Fork and damper fully compressed
Compression spring and spacer removed
Lee
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2022 R1250RS White Sport
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(01-24-2023, 05:37 PM)Enzo24 Wrote: Their volume spec for the ESA fork is about double (304ml) of what I drained from the ESA fork (155ml). The air gap they spec is 65mm. Adding fork oil to get a 65mm air gap takes about 160ml, which corresponds to what I was able to drain. So I'm guessing that the Haynes volume spec is wrong.
The BMW factory service manual has the ESA fork oil capacity as 304 ml left and 682 ml right.
The problem with the Haynes manual is it just says, for the left fork leg, "Support the fork upside down in the container and allow it to drain for a few minutes."
If you don't want to completely remove the fork innards (as specified in the factory manual) I have found that it takes about 20 minutes of pumping the upside down fork leg up and down (being very careful not to pull the fork tube out of the slider) to get all the oil out. It then takes about 30 minutes of pumping, after filling with oil, to bleed all the air out of the fork tube so that the 65 mm level reading is accurate.
My experience is that draining and refilling the right fork legs is much less effort. Here are my service notes re the left leg:
- To drain the oil properly, pump the outside tube up and down while the fork is inverted. It takes a lot of pumping to get it all out.
- When filling the oil, pump the outer tube up and down all the way until no more bubbles are coming up. It took about 30 minutes of pumping before it stopped.
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(02-03-2023, 08:38 AM)mspratz Wrote: The BMW factory service manual has the ESA fork oil capacity as 304 ml left and 682 ml right.
The problem with the Haynes manual is it just says, for the left fork leg, "Support the fork upside down in the container and allow it to drain for a few minutes."
If you don't want to completely remove the fork innards (as specified in the factory manual) I have found that it takes about 20 minutes of pumping the upside down fork leg up and down (being very careful not to pull the fork tube out of the slider) to get all the oil out.
...
Michael - thanks for again a useful post on how to work on the bike.
I have never done a fork oil replacement job so no documentation or video on it. One of these days (soon?) I will be doing this, since it was last done (at the dealer) around 36k miles and the bike is now at 60k. They claimed that it was not a simple job and they actually took a whole day to do it ... likely not working on my bike all the time during that visit. Anyway I was not impressed enough to not want to bring it back to them, and the other master technician I like moved out of BMW motorcycle service.
I take it that the BMW service manual has the innards being removed for inspection and replacement? Sounds like all you did was change the oil, right? I think that if I am going to go to all that bother I would probably want to replace wear items like seals etc. but I think that special tools may be required.
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The factory procedure for simply changing the fork oil is to remove the innards. My guess: that this is the simply the fastest way to get all the old oil out. Professional mechanics don't have the time to spend 20 to 30 minutes pumping the fork leg to drain or refill the oil. I have never removed the innards of either leg because to remove the bolts holding them requires more force than I have the means or the courage to apply. I don't have a vice and any good way to hold the fork leg while applying that force.
Even if you do remove the damper, there is still the step after reinstalling it and pouring in the oil where the factory manual says "Repeatedly move piston rod (1) of the damper unit up and down. Air is expelled from the damper unit. Allow the oil to settle for a few minutes. Repeat the procedure until the oil is free of bubbles and the oil level no longer changes." In my experience it takes 30 minutes of constant pumping to "bleed" damper in this way. What professional tech has time for that? My guess is they leave the refilled fork sitting for half a day and hope it bleeds itself. Hence, fork oil change takes a whole day.
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Disclaimer: I've not done BMW forks, only Japanese. I replaced the cartridges in my FZ1 with AK 20's from Traxxion. On my Tenere I used a shim pack, springs and valves from Cogent. And I've replaced seals and bushings(slides) in several different Japanese bikes for friends.
I've always removed the forks and disassembled them. Had to buy a few specialty tools, I now have a "fork" drawer in my toolbox. Unless it's a recently serviced fork, I replace the bushings and seals. Draining is easy, turn the fork over and drain. Pump the cartridge/damper a few times and it's empty. Do the same refilling, usually takes a minute or two. If I did this more often I could probably do a set of forks in a couple of hours. I will say it's a filthy job but with a clean workspace it's really not that hard with a little patience. Keep everything in line the way it came apart and replace in reverse.
All that said, I have no idea what the ESA adds to the procedure. Or how similar BMW forks are to Japanese. So, you should probably disregard this post as the inane ramblings of an old man.
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(02-03-2023, 10:59 AM)mspratz Wrote: The factory procedure for simply changing the fork oil is to remove the innards. My guess: that this is the simply the fastest way to get all the old oil out. Professional mechanics don't have the time to spend 20 to 30 minutes pumping the fork leg to drain or refill the oil. I have never removed the innards of either leg because to remove the bolts holding them requires more force than I have the means or the courage to apply. I don't have a vice and any good way to hold the fork leg while applying that force.
Even if you do remove the damper, there is still the step after reinstalling it and pouring in the oil where the factory manual says "Repeatedly move piston rod (1) of the damper unit up and down. Air is expelled from the damper unit. Allow the oil to settle for a few minutes. Repeat the procedure until the oil is free of bubbles and the oil level no longer changes." In my experience it takes 30 minutes of constant pumping to "bleed" damper in this way. What professional tech has time for that? My guess is they leave the refilled fork sitting for half a day and hope it bleeds itself. Hence, fork oil change takes a whole day.
I agree with your assumption and maybe that is what happened in my case, although from what they said they gave me the impression they did not have much experience doing this and got into some difficulties. Who knows.
Every process that I saw for replacing the fork oil involved removing the innards and for precisely the reasons you gave, I backed off doing it myself. It is done relatively rarely so it makes sense that this is one of the times I bring the bike to the shop. BUT if they are not going to do it per the manual then that also gives me pause.
Maybe changing the oil your way is the best approach. After all, most of the oil is changed and that is way better than none.
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Grumpy Goat
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(02-03-2023, 09:59 AM)Grumpy Goat Wrote: I think that special tools may be required.
Here's the tool to compress the spring.
Lee
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(02-03-2023, 11:56 AM)Liteitup Wrote: Disclaimer: I've not done BMW forks, only Japanese. I replaced the cartridges in my FZ1 with AK 20's from Traxxion. On my Tenere I used a shim pack, springs and valves from Cogent. And I've replaced seals and bushings(slides) in several different Japanese bikes for friends.
I've always removed the forks and disassembled them. Had to buy a few specialty tools, I now have a "fork" drawer in my toolbox. Unless it's a recently serviced fork, I replace the bushings and seals. Draining is easy, turn the fork over and drain. Pump the cartridge/damper a few times and it's empty. Do the same refilling, usually takes a minute or two. If I did this more often I could probably do a set of forks in a couple of hours. I will say it's a filthy job but with a clean workspace it's really not that hard with a little patience. Keep everything in line the way it came apart and replace in reverse.
All that said, I have no idea what the ESA adds to the procedure. Or how similar BMW forks are to Japanese. So, you should probably disregard this post as the inane ramblings of an old man.
I do not think that the post is "disregardable" in the least, especially seeing the topics of some of the other posts on motorcycle fora ... You are actually talking about working on the bike which, for me, is the best kind of post.
You have infinitely more experience than me when it comes to changing fork oil as I have never done this particular job. But from what I have read, there is a significant difference between electronically adjustable suspension and passive systems, with the former being not as straightforward. With your experience I think you'd have a great headstart on this operation.
To anyone who has done this or is planning to do it on the RS - Please consider documenting the operation in an article (with some pictures ..?) for the Forum / website. We all learn from each other, after all.
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02-06-2023, 10:08 AM
(This post was last modified: 02-06-2023, 10:23 AM by mspratz.)
(02-04-2023, 07:16 AM)Lee Wrote: (02-03-2023, 09:59 AM)Grumpy Goat Wrote: I think that special tools may be required.
Here's the tool to compress the spring.
The BMW tool probably makes the job easier, but it is very expensive. I use two tie-down straps and this thing: https://www.homedepot.com/p/BESSEY-2-1-2.../205971654 that I bought for $8 a couple of years ago, but is now $15. The Haynes manual suggests making an equivalent tool, but that's a lot more work and probably more expensive. To get this clamp ready for use, you need to pull the large flat knobs off the ends of the three screw threads (just back the screws out until the end bits come off), and then remove the middle screw thread completely. The two side ones then fit into the holes in the top of inner fork tube of the right fork leg. You can use the tie-down straps to compress the leg while you get the top bolts undone. It doesn't take much effort to compress the spring once you have this thing in place, so non-ratchet or ratchet straps will work just fine.
Here is the right fork leg, with the clamp and straps in place, compressed and ready to be dismantled. If you zoom in you'll see the plastic covered strap hooks hooked at the bottom of the leg:
Put a bit of gorilla tape on the inner center of the clamp so it doesn't scratch the pretty gold-colored outer fork tube.
You will need to make one more tool. You need a 50 mm washer with a 14mm hole in it, and about 1 mm thick. Ace Hardware has them. You then cut a slot from the hole to the outer edge. I used my Dremel to cut the slot, but you could probably clamp the washer in a vice and use a hack saw:
In the first photo, you can see the modified washer in position on top of the 3 inch metal part of the inner tube. It holds the spring compressed while you loosen the lock nut and remove the top bolt of the fork piston.
You don't need these tools to do the left fork leg, just the right one.
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Nice ... very ingenious solution Michael.
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Whoa! Love the C clamp. I do similar but spent more money to do it.
https://traxxion.com/product/fork-service-tool-kit/
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(02-06-2023, 11:50 AM)Liteitup Wrote: Whoa! Love the C clamp. I do similar but spent more money to do it.
https://traxxion.com/product/fork-service-tool-kit/
Looks like a nice toolkit! Thanks for the info.
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(02-06-2023, 03:12 PM)mspratz Wrote: (02-06-2023, 11:50 AM)Liteitup Wrote: Whoa! Love the C clamp. I do similar but spent more money to do it.
https://traxxion.com/product/fork-service-tool-kit/
Looks like a nice toolkit! Thanks for the info.
Nice but it look like you still need the straps (not included) to compress the spring. Not bad price though, especially if you own multiple bikes and can spread the cost.
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02-07-2023, 07:56 AM
(This post was last modified: 02-07-2023, 08:51 AM by Lee.)
Looks good Michael.
A few years ago I posted a thread here showing what a guy did for home made tools for the fork oil change.
Post #20 and #21 in this thread show some DIY tools for a fork oil change.
https://www.r1200rforum.com/threads/fork...nge.41257/
There's also two videos, post #99 and #113.
I think #99 did not remove the springs.
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(02-07-2023, 07:56 AM)Lee Wrote: Looks good Michael.
A few years ago I posted a thread here showing what a guy did for home made tools for the fork oil change.
Post #20 and #21 in this thread show some DIY tools for a fork oil change.
https://www.r1200rforum.com/threads/fork...nge.41257/
There's also two videos, post #99 and #113.
I think #99 did not remove the springs.
Looks like some good information in there but some chaff may need to be sifted out.
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I just completed the fork oil change on my 16 RS using the Haynes manual for the bike and the Youtube video from Baking Biker. Although the video indicated the air gap requirement for each leg he did not say what amount he poured into each leg, he only set the air gap depth. In the Haynes manual no mention is made as to removing the internals of the left leg/ESA leg to get all the oil out to match the required volume of 304 ml stated in the manual. I dumped out about 200 ml from the left leg and then let it drain to get out another 10 ml but that was it no matter how many times I pumped the fork. So, in the opinion of the forum is this good enough or should the fork be disassembled to try and get out more oil? The seal or gasket rings for the damper rod bolt in the bottom of the fork is not cheap at $9.73 each, just saying.
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11-30-2023, 09:20 AM
(This post was last modified: 11-30-2023, 09:23 AM by Lee.)
(11-29-2023, 07:05 PM)Oldrider51 Wrote: the Haynes manual no mention is made as to removing the internals of the left leg/ESA leg to get all the oil out to match the required volume of 304 ml stated in the manual.
My picture in post #9 is how a Master Tech did it at a BMW shop on our 2016 RSs.
The rod is in place in the picture.
Lee
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