I haven't posted much about my bike - today I did a baseline dyno run which is posted in the members garage. I was pleased to see that the bike peaked at 59 HP which is pretty much what we would expect with the few mods that I've done. My goal with this bike has always been to keep it as stock looking as possible - eventually it will get parked in the living room. When I first purchased it my main concern was to make sure the engine seals were ok - everything else appeared very clean. After extensive leak testing I determined everything was fine. I put on the Tyga pipes, reeds, DynoTek coils and HRC PGM. It's always run well, but has flat spot at about about 1/3 throttle (very rough approx, but it's clearly when on the needle). When I initially jetted I had added a 0.5mm shim under the needle. A week ago I removed the shims and to no surprise it just changed where the flat spot occurred, now it's at a little more than 1/3 throttle. Initially it was happening around 6k rpm, now its a little higher up closer to 8k rpm. The plot follows a similar curve as most of what I see posted, but obviously the bike isn't as modified as some of the other members.

The shop placed the air/fuel sensor in the right exhaust which is included in the posted plot (members garage). I feel good I've got the main jet right - could even drop it down a size. But mid range is just too lean - explains the flat spot. Since I don't have a box load of needles with different profiles.....I think I'm gonna just learn to live with as I'm not going racing, just maybe a track day here or there. However if I were to try to change it...I think I'll need to source some stock needles and mill flat spots (old school jetting). I soldered cables onto the mixture screws so I can adjust them on the fly. But since the flat spot is when I get on the needle, I haven't been able to work it out with the mixture screw.

I suspect more than one of you guys have been down this path have some ideas on how to work out the flat spot. But please don't tell me to go get an MC21 I like the MC28 look and don't need that extra 5 HP.
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MC28 SP