Hi everyone, Thanks to everyone's help with the last thread I've got my bike to run, but very poorly. I had to redo the spark wire to boot connection a couple times to get it to bite properly, and now I believe it's running on all cylinders. So far, it runs with the airbox off, but open the throttle and it dies, even with a slow roll on. With the airbox on, it will fire up like it's going to run, then dies within a second or so. This seems to be relatively independent of the idle speed screw. The fuel pump is making noises, but I'm wondering if it's not delivering enough fuel. It was turning on just about every time after cranking for a couple seconds, not sure if that's normal. Has anyone had this issue before? Do I just need to strap my tank to the ceiling before messing with float levels in the carbs? P.S. I wanted to share the difference between new and old airbox boots. Very worth it for 50$
It occurs to me after writing the post that I should probably put in a cheap replacement fuel filter just to rule that out too.
1988 FZR250, is that a 2KR or a 3LN? I just checked back on your other thread, your bike is a 3HX1 which is a hybrid of sorts if I am correct, 2KR frame and 3LN engine specs with respect to the cams and an EXUP - correct? 2KR carbs are far less problematic than 3LN, however all issues are known and all problems solvable. Others have also had problems with some various inline fuel filters becoming blocked very easily. Have to checked the fuel filter within the tank itself attached to the outlet on the inside? One thing which is easy to do to and check fuel in general is to see what the fuel level is, it's very quick to do and requires just a piece of clear plastic tube - see the image here in this post https://2fiftycc.com/index.php?threads/my-fizzer.872/page-32#post-15537. Then you will know if you're fuel pump and filter are working properly or blocked. If the fuel level is correct, then move on to other potential issues hope this helps
3HX is a 2KR with EXUP exhaust headers and servo motor. 1989 is 3LN1, but so is 3HX. It is a crossover year. When in doubt, check part numbers between models to confirm differences.
I just checked back to his first post, he's got 2KR carbs so I reckon he's got fuel flow problems over carb problems and everyone can let out a collective sigh of relief. I've never seen cam specs for a 3HX1, but if it's got an EXUP I'd bet dollars to donuts that it's 3LN1 cam timing and overlap specs - interesting beast.
Just been in the middle of moving, sorry for the delay. Everything above sounds accurate, and yes the carbs are 2kr style, the frame number on this one comes up as a 1988. The 3hx1 really is quite a strange mixture of parts. I like the method suggested to check fuel level, I might even have a hose to do it. I'll hopefully get to it soon and report back.
