I've got an older 85 KTM 250. I'm having problems getting it started the compression is getting pretty weak, but it still has alot of power, i feel it's carb problem because i've had to use starter fluid to get it to start the last couple times, it started to spit and sputter like it was out of gas the other day then shut off, i refueled it and now it won't start, so i'm feeling its a carb issue anyone else have any idea?
i had 1 of these back in the day. has a floating disc on the front with weird little spacers & a double leading shoe drum in the back, right? sounds like you are correct, it is fuel starvation in the low range. if it has a fuel filter, i'd clean/replace that 1st. then i'd take the carb off & apart, clean it with carb cleaner, blow it out with compressed air, see what happens.
Probably right but the bad thing is the previous owner had no fuel filter and no airfilter, the inside of the card has scarring, looks bad for the old girl :think
Lawman has a good tip with having a clean carb before troubleshooting. That and a fuel filter can solve alot of fuel problems. Another thing, the hard starting could be compounded by old worn-out reeds that are cracked or don't seal. If the reeds aren't chipped on the ends, just flipping them over may help. Advice from the feeble minded.
Mine had a bad crank brg on the ignition side.
Double trouble, it had a primary compression leak sucking air past the seal, and the ignition rotor air gap went all over the map causing funky spark.
Grab the end of the rotor/flywheel and see if it has any up and down movement.
These all seem like good candidates for your problem, especially the reeds. When I had starting problems with mine, it turned out to be the Motoplat ignition, lower coil. At the time, 1990, I was still able to send the ignition unit off to Ohio and have it rebuilt. That seems unlikely now, and I no longer have the info for whoever rebuilt them. It cost around $100 at that time. Good luck.:cool: