Jamesyz250

Thank you for all of this information! I never would have thought of any of this. I diddnt have any time today after work but i will definitely be checking this as soon as i get the chance. I will keep you posted!

Fras1, i appreciate the response. I will keep you updated!

Hows it going guys? Im new to yamaha club and i would appreciate any help i can get from you guys. I have a 1980 yamaha sr250 and the bike is driving me insane. The bike originaly belonged to my grandfather and he abandoned it. Once he abandoned it, my father took the bike off his hands. This was probably in the early 90's. I was just born haha. My father rode the bike here and there untill he ran into a problem with it. He would start the bike, and the bike would idle perfectly. But as soon as he touched the throttle, the bike would die. No biggie. My father told me he spent a year on an off trying to fix the bike until he finally gave up on it. Here i am now, 23 years old, and i love motorcycles more than anything in this world. My grandfather passed away and i figured it would be neat if i got his motorcycle running. The bike has not been running since 2001. The first thing i did was buy a new battery, drain the gas tank, and clean the carburetor with compressed air and some carb cleaner. To my suprise, the bike fired right up. I went to give it some throttle, and the bike died. Immediately, i knew what i was. The pilot jet was the culprit. So i pulled the carb off again and made sure that i did a thorough carb cleaning and diddnt miss anything. I fired the bike up, and the same thing happend. Long story short, i have literally cleaned this carburetor about 15-20 times. Every single jet, orfice, circut, diaphragm has been cleaned. Im really stumped on this. I thought maybe the diaphragm was bad, but its actually in great shape. So right away, i orderd a new pilot jet, a new float, a new needle valve, a petcock rebuild kit, and i also orderd a new (used) carburetor. Once the parts came, i rebuilt the petcock and i rebuilt the carburetor with the new parts that i bought. I did not buy a full rebuild kit. Only what i mentioned up above. I put the carb back on, fired the bike up, and had the same results. Now im thinking a little more like a mechanic. I want to take a look at the spark plug. I pulled the plug out and the plug was dry, white, and brand new. The bike also runs better with the choke on. This tells me the bike is running lean. I decided to take a look at that air filter to make sure that nothing made a home of it. I opened the air box up, and there was a mouse nest in my air box. There was no air filter to be found. I was absolutely certain that this was the problem. So i ordered a new air filter and waited. Long be hold, the new air filter diddnt fix the problem. Now im starting to get frustrated. I decided i would check my exaust pipe and make sure nothing made a home of that either. All is well. The next thing i decided to do was check my valve clearence. My valves seemed a little bit tight so i adjusted them to spec. I diddnt have a metric feeler guage, so i was skeptical if i was making the right measurments. After i adjusted the valves, i figured i would take my carburetor off, and try putting the new (used) carburetor on the bike with the new float, needle valve, and pilot jet. I started the bike up, and BAM. I could give the bike some gas. The throttle was responsive and everything seemed normal. I let go of the gas, and the bike stalled. So now the issue im having is the COMPLETE opposite of what it was. The bike WAS running lean and now its running rich. The bike used to idle but i could not give it gas. Now i can give it gas but the bike wont idle. The spark plug WAS dry and white. Now the spark plug is carbon fouled. I can even take the bike for a spin around the yard now but then it starts to back fire a little bit once it gets warmed up. The bike is also very hard to start all of a sudden. Could i have made my valves to tight? To loose? I am really at a loss with this bike. I know this short story is alot to read but i sincerly thank anyone who takes the time to help me!

Hows it going guys? Im not new to forum but i am new to yamaha club. My name is james and i love working on motorcycles. Look foward to speaking with you guys.