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2016 R1200R ESA fork, what happens if ESA fails or plug is disconnected?

3384 Views 43 Replies 5 Participants Last post by  K1600R
Anybody here knows what happens to an ESA fork leg if ESA fails or the plug is disconnected? What state would the fork be in? How would the bike behave?

I know that only the left leg is active so the right one would not be affected.

I have some trouble connecting my R1200R ESA fork to the K1600 ESA controller ;) They are quite different it seems, R1200R has two wires and K1600 has four, even though there is no preload adjustment up front on the K1600.
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I think I'll take them both apart and see what differs and go from there, non ESA bikes are very rare here, I can't remember ever seeing one actually, so finding a used pair would probably be next to impossible. I think I need to look at the parts diagram and try to understand what differs and what parts I'll be needing.
Unfortunately the gold staunchion part numbers are different left and right, so it certainly won't be a straight swap.

Maybe the right gold staunchion is physically the same as the silver non-ESA staunchions and you could source a second one of those.
I have been studying the part diagrams now and the gold stanchions actually do seem to be the same left and right, part # 31428552602, if they are the same as the silver non ESA, apart from color, is hard to tell though.

The internals in the right side passive leg differs quite substantially from the non ESA legs in the stanchion department, the damper units on the other hand looks very similar but obviously impossible to know how much they differ internally.

I don't know what kind of adjustability there is on the non ESA legs, I would guess spring pre-load, compression and maybe rebound? But I guess there are non on the passive ESA leg?

Given that the gold stanchion really is the same as the silver one, this seems yo be what is needed to convert to non ESA:

Cover (31428547341) £57
Set compression spring (31428550088) £58
Spacer tube (31428548677) £14
Set of gaskets (31428548263) £71
ISA screw (M8X25 8.8 MK ) (07129906017) £7
Gasket ring (31428557617) £3
Set, plain bearing (31428548264) £42
Damper unit, left (31428566555) £384
Damper unit, right (31428566556) £403
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Looks like you at least have the option.
I don't know what I was looking at re the L-R Gold ESA stanchions - as you say, they're the same part number, and there doesn't seem any logical reason for the silver and gold to be physically different.
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So, a quick update on the fork issue, I have found that the ESA forks are Sachs units, and non ESA are Marzocchi's, so no parts are interchangeable obviously.

Given that I put some more effort in trying to find out how the ESA fork is controlled. After some digging I managed to find that you can feed 0-6 volts to the fork, the resistance is 2 ohm so that gives 0-3 amperes, where 0 amps is fully stiff and 3 amps is fully soft. I think the hardest setting the bike will set is about 1 amps. I didn't do a very scientific test, but just sitting on the bike rocking it while varying the voltage felt like it's not very linear, it's a pretty narrow window where you get usable dampening. I think in practical use I need to be able to control the voltage between 2 and 5 volts, so between 1 and 2.5 amps.

Initially I could just put a fixed voltage of say 3 volts and leave it like that. As a second step I could look into some way of adjusting it.

I also sorted a complete K1600 front ESA suspension unit, and removed the stepping motor that adjusts the dampening. The plan is to connect it to the bike to trick it into thinking that the front unit is present and not throw a fault code. ;)
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