Has anyone fitted a kit to the Showas that gives a better ride?

Alternatively, how do I go about altering the shim stack and does it make a decent difference?

If you buy different internals you’re basically doing the same thing but someone else has done the leg work although the quality of the internals will likely be higher as well.  But it’s still someone else’s interpretation of what they think is better. If you have the patience your own stack will be more tailored to you. I wouldn’t rule out oil viscosity and levels as a starting point to try. 

No the shims do differ although there may be more than 1 of the same shim in each stack. The pic below is the sort of shim stack that they have installed.  I seem to remember Ian G possibly left out shims on his forks so he’s best placed to comment on its effect. Generally most seem to complain about the rebound on the axial Showa’s. If that is the area you want to improve in isolation then shimming is the only way with the stock internals.  Oil type or quantity and springs affect the fork as a whole. 

Hi Steve,a lot of what I felt with my Mille is down to weight  ( I put on a bit) but more so down to the frankly strange setup the Showa's come with.

Firstly,I agree they are much too harsh in compression and there are no adjustments externally that will help with that,as it's mostly it's down to shim selection. More importantly they are also harsh and sadly lacking in rebound which makes the ride uncomfortable and also causes the forks to extend back quickly while cornering which can cause the bike to run wide.

This observation is also echo'd by Maxton among others so has some validity.

The Tuono will probably be affected slightly differently due to the rider weight distribution being more rearward but I seem to recall the stock rebound stacks being identical between the gen1 Mille and a 2009 Gen2 Tuono while the comp stacks were minus one 17mm x 0.015" ?  shim on the T to allow for less rider weight over the front.

I went the cheap route on my Mille and just removed one shim from the comp stack and added it to the rebound valve.  Actually no I didn't, I also flowed the piston ports and lapped the shim mating faces, I did stop messing there though.

This made a noticeable difference to the overall ride,especially as the bike now held a line and went where you aimed it,in fact I surprised quite a few 600's on track by turning inside them. As an aside I also fitted the Green SKF seal and wiper sets while I had the forks stripped which helped.

Fast forward to my Gen2 Tuono and after seeing what Dave @ Obsession Engineering did with his Tuono I spoke with him and decided to go the same way with totally new KTech valving and let me say now,what a difference that makes to the bike. The shim stacks are much more progressive and not just open or closed like OE.   I was so impressed with the valving I also got a set of their clicking compression adjusters as they have a much more nuanced taper, so each click makes a difference unlike the Showas which go from closed to fully open in around one turn. They had a policy of not selling such kit outside of their dealer network at the time though

 Most of the Showa so called adjustments are all in the head though as after the first turn out both the Comp and Reb adjusters are pretty much fully open and doing nothing thereafter.  

This should help if you've not already seen it

Ian, did you just move one shim to make a noticeable difference? Which shim did you move, size wise?

Why did you add to the rebound, was the aim to slow down the rebound?

Just watched another vid on yt, really good explanation how the stack works. I wonder  if its possible to get different sized shims to experiment with.

Checked out my sag with rider without bike gear on. 30mm on the Showa front end. I had to raise the pre load adjuster by 3 lines to achieve this which is now raised to the 7th line, so I had too much  pre load, is 30mm enough?

I have an Ohlins on the back with a 31/95 rated spring. Pre load is fully wound off and sag is at 25mm. Opinions?

 highlights the backend even more which even with all preload wound out still feels plank like. Since buying the Tuono many years ago, Ive shed about 12kg now am about 72kg without riding kit so Im thinking front and rear are oversprung and front would benefit from some adjustment to the shim stacks or valve replacement. 

New seals and bushes, stanchions polished, fork spring rate to be checked and probably replaced with lighter ones, oem comp and rebound valves to be re shimmed to my weight. 

Apparently removing all pre load is not a good thing and I also didnt take the rear sag measurement at the rear wheel axle, so now the Ohlins sag is reset to 35mm properly.

Should get the forks back in a couple of weeks.

RS said that the internal anodising around one of the bushes has worn, rather than the bush itself, on both forks. A sign the anodising isnt too brilliant on these forks. He marked the forks so I could orienate them with the wear lateral to the bikes axis, and recommended replacing the oil every 3k miles. 

Oem springs were measured at 1.02kg and replaced for my weight for 0.93kg items. Bushes and seals replaced and Silkolene RSF 7.5w oil with 120mm air gap used. Ive set front sag to 35mm and the forks are on the 4th line above the top yoke. Rebound and comp adjusters are oem and are both at 1.5 turns out for each fork. 

Rear Ohlins sag is set at 37mm and comp is 15 clicks out (max of 24) and rebound is 30 clicks out ( max of 58!!). 

Now to get it on the road and see how it rides.

Front end is definitely improved, not as harsh, but Ill probably replace the fork oil soon for something thinner and experiment with air gap. The better front end however now makes the back feel harder. Ive wound off the rebound and comp adjusters more which helps but Im definitely going down a spring weight on the Ohlins.