Tuesday 16 January 2018

Rear Shock & Track Sessions

I just realised that I never updated this blog in the later half of last year so I owe it to people now even if it is a few months late coming.

Since the last update, I haven’t done a lot more with the EFI side of things other than improve the cold starts.

I ended up doing two more track days on the bike in 2017 which were in the dry so I could really see the areas which needed improving on the bike.
The first track session was carried out with the same setup as I had run in Mallory Park in February 2017. This session highlighted that the back shock was way underdamped and also a little undersprung. (not that I didn't know that already) I also felt I lacked just a little bit of drive out of corners but felt that was mostly my own fault for not being spot on with my gears.

After that first track session, I made the following changes to the setup

  1. Installed new custom rear shock
  2. Set up front and rear preload to my weight with the new shock
  3. Installed 54T rear sprocket for slightly shorter gearing

I had purchased a Nitron rear shock some years back supposedly designed to fit the mc22. When I came to fit it, it became clear the top mount was too large and fouled the frame. Nitron advised the frame would need to be ground down to make the shock fit which I was not willing to do. I made several enquiries in the years that followed to try and find a proper replacement shock for the basic and now tired stock unit. Penske were the only other company that listed a shock to fit the mc22 but that had the same issue as the Nitron. The issue was actually worse as their top mount was larger and so would need even more material ground from the frame. I approached BG Motorsport, my local Ohlins dealer, some time back about building a custom shock specifically to fit the mc22 with my requirements built in and they were quite happy to relieve me of some cash to build a unit for me.

The shock was completed at the end of June and I must say I was very happy with how the whole package turned out. The entire assembly including the remote reservoir fits nicely under the stock fairings making it quite discreet.

Rear Shock Installation - RH Side

Rear Shock Installation - LH Side

From the get-go, the improvement the shock made to the handling was obvious. Even without making any adjustments, the bike tracked the road much better and felt much more stable on the road compared to the stock unit.

After setting the preload on the front & rear to my weight, this improvement just got bigger.

I also installed a 54T rear sprocket on the bike to get slightly shorter gearing. This was the shortest I could go while sticking with the standard 428 pitch chain. I may look into the 520 conversion in the future to give me more gearing options.

On the second track session after the above adjustments were made, the difference in handling was night and day. I am extremely happy with the way the bike handles now compared to the stock setup. I do have a few more items on the wishlist but these are things that will get done over time.

I have been playing around a bit with some software that overlays data from the ECU onto video which seems to work quite nicely. The GPS data was captured from a smartphone so it is not very accurate and lags a bit. That just affects the track map and lap times really. Still, it makes it very handy to review the video and get an idea of what the bike was doing when.