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Discussion Starter · #1 · (Edited)
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:

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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

Automotive tire Rim Cylinder Automotive wheel system Circle

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.

Rectangle Composite material Gas Aluminium Auto part

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.

4 Posts
Discussion Starter · #3 ·
Awesome stuff and a good upgrade. You’ve done it a lot easier than me which is great because it lowers the amount of effort for those that aren’t as mechanically inclined. Kudos!
How the hell did you find a bike that year with so few kays though is what I want to know 😲👍🏼
Thanks I think I was lucky to find such a good bearing supplier.

The bike was a lucky find indeed, sadly I have no way of knowing it's history as I got it in an auction from an insurance broker. Though a search of the MOT history showed something interesting.

For the first two years it did the normal sort of mileage for a recreational bike, nothing unusual. But for the last 12 years it did exactly 200 miles every single year, give or take a mile or so at the most. It's like the owner did exactly the same trip (or combination of trips) each year and absolutely nothing else. Weird.

4 Posts
Discussion Starter · #4 · (Edited)
First ride report

Recap of settings and measurements:

Rebound damping: Set to medium.
Fast compression damping: Minimum (max turns anticlockwise).
Slow compression damping: Minimum (max turns anticlockwise).
Preload: Maximum
Static sag with 100kg rider (100kg = complete weight including all clothing): 60mm not sure what happened here, as per my previous post I thought it was a lot more.

Overall impressions

Well that was an interesting experience, here are my take away points.
  • It felt like I had functioning rear suspension, very different from the previous ride where it genuinely felt like I had none at all on many occasions.
  • Due to the dramatic change in feel I expected it to be night and day terms of comfort, sadly this did not seem to be the case and whilst it was an improvement I still cannot ride the bike for very long.
  • I added a cable tie to the piston rod to see how much the shock compresses in use, pretty much all the way just stopping short of the bump stop when hitting the bigger holes. A higher spring rate is certainly in order.
  • It feels taller than it did before even with the extra static sag, I assume this is down to the slightly increased shock length (I may be wrong here, in my mind it is about 20mm?).
  • It has really highlighted the poor front suspension to a shocking degree, with functional rear suspension the front now feels almost rigid.
  • I did not experience any handling issues during my short 50-60mph ride around the twisty local roads, that said I've been riding so long I often don't notice as I tend to auto-compensate without conscious effort.
  • It also highlighted the seat, on my other bikes the seat foam is much thicker and serves to cushion the impacts that the suspension does not fully address. It has a huge effect on the comfort of the ride in terms of impacts and is often overlooked, My VN800 had a much harder ride until I changed the seat.

Automotive tire Automotive lighting Motor vehicle Automotive design Vehicle

Automotive tire Motor vehicle Vehicle Automotive design Car

Plans going forward
I'm unsure as to whether I should change the spring right now. Obviously if I plan to keep the bike I'll need to address it but for now it's not bottoming out and if I can't make the bike comfortable enough to use I'll need to sell it. Thoughts?

I need to address the seat. I will be removing the stock seat and temporarily rigging up something from another bike (or maybe layering foam over the current seat) to see how much that will help.

I'd like to address the forks, they're just far too harsh. Not entirely sure what to do here. Thinner oil perhaps?

4 Posts
Discussion Starter · #7 ·
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
Thanks for the suggestion. I may decide to try that at some point.

Yeah In my very humble and non expert opinion you are way undersprung
There’s many different options for seats but I too find that mine leaves me sore but it’s after a few hours
The forks…. The spring rate in the e stockers was ok from memory for most people it’s more the damping
There’s emulators you can try as well as different oil viscosity and levels you can play with
Personally I’d keep my eye out for a cheap front end from a sports bike you can swap out
Thanks for the input, much appreciated. I've been doing some reading and I'm coming to the same sort of conclusions.

Rear needs a higher spring rate for sure.

I like the front end swap suggestion, I've read some threads here talking about a ZX6 conversion with adjustable preload will be looking to see what is available here.

I also have a KLE500 front end laying around, maybe I should turn this thing into a jacked up offroader, that should sponge up the bumps. 😋😋

I'm going to have to put this little project on hold for now though as we are about to set off on a European tour for a month. But I'll update the thread with any further developments.
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