RE: 35cc Carb Adjustments
The problem may be related to the ratio L and H needle.
As you know by now, good running can be achieved with a lean L-needle and rich H-needle or vice versa. If the running gets too rich in midrange, it is a rich L-needle combined with lean H-needle. The cure to look for is to lean out the L-needle, and readjust the H-needle until good transition is regained. If you are a daring kind, you might want to experiment with the fuel lever height inside the regulating carb section.
Lower the lever slightly, and your top end will get leaner so you have to open the H-needle more. Right now it slipped my mind what it does to midrange. If it makes the condition worse, just bend the lever the other way. [8D]
The 25mm header I shipped today may improve the situation as well, since it improves power over the total range