I had bought 2 2001 GP1200R's from someone a couple months ago. There are no mods to it. One runs perfect, the other not so much. The troubled one had the carbs rebuilt at a shop, one piston was replaced (before I purchased it). Here are its troubles now: upon startup, I have to open the choke and hold the throttle all the way down and hold the start button, once it fires up, i have to roll the choke and ride around for a min. for it to warm up, even after its warm, I have to fiddle with the choke and throttle to start it up every time.
Also I noticed that if going about 10-15 mph, i give it full throttle it will bog and sometime die, I have to ease into it and once i hit about 20-25 and the high end valves open up, it takes off like a rocket and is fine.
Lastely, after I run it for a few hours, it will bog down and not go above 45, then not go 30 and keep dropping and not go faster than an idle. After it cools off for an hour it will be fine and once it funs for a few, the same things happens. If I let it cool off for a day, then its fine for a few hours again.
I had noticed my throttle cable is a little loose compared to my other ski.
After reading, I have a few thoughts, I was thinking to replacing the temp sensor (even though no lights or alerts show up on the display). Install a d-plate, and install a primer mod. As for the bog down after a its ridden for a while, I heard that a piston can heat and swell and seize in the moter and once it cools it shrinks back and resumes working again but I also read that a bad temp sensor will bog the motor exactly as described, thinking the motor is too hot and for safey, bog the motor so that it doesnt get burned up.
Can anyone please help?