Hi all: I did a lot of research on the pros and cons of installing a twist throttle on my 2001 DS650 and the pros outweighed the cons so I did it! I bought the Motion Pro and installed it and I am thrilled. No more thumb fatigue and since I rode dirt bikes and motorcycles most my life, twist throttles are for me. Now I know that most twist throttles are PUSH/PULL systems mainly on road bikes and the thumb throttles are spring assist I spose because your thumb won't have to swing the thumb **** back but I wish the carb return spring was stronger to pull the cable back. I've been trying to think of a mod inside the side cover like adding a booster spring that the 'wheel' would push against while throttling up and then the spring could act like your finger helping the 'wheel' return against the idle pin. The area is to the lower right area where there is room for a spring and the wheel has a ledge that could push against the spring.
Question is, am I making this more difficult that it needs to be? I have a stiff spring about 3/8" round and about 1 inch long and should sit in there fine. I have no shortage of springs and I have a Dremel! Problem is how to keep it in place short of gluing one end in place. I am sure this is an aftermarket carb and maybe that is one reason for a so-called weak return spring. Can I replace it with a stronger one? I want to buy an OEM Mikuni BSR42 carb but can't locate them. A link would be appreciated and I'm not out to buy cheap. Has anyone modded for a stronger throttle cable return? Any help would be appreciated. Luckily this is my only hang up- Sometimes the idle hangs up until it drops and sometimes it just drops fine. I am out to eliminate one possible cause and I have ordered a new intake sleeve and my diaphragm is fine and has been checked. Other than that, the carb operates responsively!! With the engine off, I test my twist throttle and I hear it hitting just fine but sometimes it it don't and maybe more-so when it's running some of the time. Photo is what the carb throttle spring area looks like with cover removed. Thanks for your help.