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Hi all, I hope this might help someone out there.

I know it's been done a bunch of times before (also done a lot on the Versys forums) but I thought I would record my experience of swapping the shock on my 2008 ER6 for one from an 2007 R1 with as much detail as I can, maybe someting will be of use to someone.

Why am I doing this?

It's 2022 and I recently purchased a 2008 ER6 (with less than 5k miles on the clock, that's not a typo) which I quickly found out that I can't ride for more than about 10 miles.

The roads around here are dire, potholes everywhere some over 4" deep even on fast moving roads and the ones that are filled are botched badly leaving a mini speed bump (often surrounded by ignored potholes).

The stock suspension can't seem to cope with all this and feels like I'm riding a hard tail every time I slam into another damaged section of road and my back can't take more than 10 miles of it (adjusting the preload does not have any noticeable effect at all on this).

I have a selection of other bikes and they manage ok with the conditions, the ER6 is the harshest of them all by a mile.

In my 40's with all the usual aches and pains of life.
Lower back's not 100% but not wrecked either, it gets on ok with my other bikes.
I weigh about 100kg in my usual gear
I'm 185cm tall
Owned many different bikes.
Decent DIY mechanic.
Around 350,000 miles ridden (almost no motorway miles).

What kind of riding do I do?
Steady A and B roads, no motorway or greenlaning. Nothing really fast, I got tired of all that years ago.

What are my goals?
Just to improve the suspension in terms of comfort enough to ride without back pain for a full day and to do so without spending a small fortune on a top spec shock. Happy to sacrifice some high speed cornering capability if needed, it's no use to me. I am in no way looking for perfection here, just comfort.

The "new" shock.
Purchased from Ebay from a 10k mile crashed bike for the sum for £60. Donor bike was a Yamaha YZF R1 from 2007. Shock looks to be in good condition.

This is not mine, it's just to show the type I have:

View attachment 140697

What have I done to make it fit?

Well the R1 shock runs M10 (10mm diameter) bolts and the ER6 shock runs M12 (12mm diameter).

The shock is to be mounted "upside down" so to speak. With the reservoir end nearest the rear end of the bike with the damping controls facing outwards to the right of the bike.

At the reservoir end I am fitting two flange bushes into the swing arm holes to reduce the stock 12mm holes down to 10mm, They are 7mm long and simply push into the holes for a nice snug fit. The part number form the supplier here is as follows:

FMB1007DU Flanged Wrapped Steel Plain Backed Bush 10x12x7mm

View attachment 140698

At the other end of the shock is a needle roller bearing, this can simply be modified by pushing out the tube in the middle known as the inner race ( also confusingly called the "inner ring") with your finger and replacing it with one that has an M12 hole instead of the original M10.

The part number form my supplier is:

IRT1225-2 Needle Roller Inner Race 12x17x25.5mm

It just looks like a small steel tube.

View attachment 140699

The two bushes and and the inner ring/race came to less than £10 delivered even at post-brexit rip off prices.

Then it came time to install it.

Firstly I found that the fittings on the new shock are slimmer than the old one so I had to add a couple of M12 washers to the top mount between the frame and the shock eye (i put them on the outer side only as it helps the rebound damping screw projection avoid fouling the frame, it'll make sense when you see it). And I think one maybe two M10 washers on the bottom end.

The new shock is slightly longer so I had to lever it a little to get the eye hole to align with the swing arm holes, a bit fiddly but a couple of attempts and it was done.

To start me off I have set the Slow and High speed compression damping to minimum.
The rebound damping to normal.
The preload to maximum (see below).

The spring
This is pretty important, and not something that I have overlooked.

The stock ER6 has a spring rate of 17.3kg/mm (as per the Racetech website)
However I am currently running the standard R1 spring which has a spring rate of around 9.4kg/mm (as per the Racetech website.)

As such, rather than measure it, I would simply describe the static sag as "extreme" even with the preload set to max and something which I intend to address next, I can order springs easily enough.

However for now I will be taking a short cautious test ride in the morning and reporting back with my findings and next part of the plan.
Do you need a steering damper? If so look at my thread and let me know your handlebar setup. You can have it professionally 3D printed for cheap or if your know a CNC shop
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