RD250

It couldn't be simple could it? Following on from Fault Diagnosis I (FD I), we have that other fault to figure out. I have left in the symptoms (in Italics ) that built up to this fault coming about as it paints the picture for how we went about investigating this fault. You should know the cause of FD I so try and find what caused the next snag. Symptoms The bike was on the dyno the day before having recently had a new ignition fitted and was running well with good power and safe temperatures. Engine started well on choke. In the waiting area for the Pembrey practice session; the bikes tick over was noticeably high with the right cylinder temperature climbing at a much higher rate to the left. Right pipe was running smokier than the left  which would seem to balance somewhat when revved. During riding temperatures rose to near correct running temperature with left reading slightly lower at 138/149 max.  Power delivery was very lumpy, bike seemed much happ...

This is the first in what will no doubt be a series of fun fault finding exercises. I will present information to you as I found it then talk through my process of elimination to find the fault. I'm hoping these will be useful in helping you recognise a problem with your bike better through the faults I have come up against. Some of these faults are very complicated and have multiple answers. In these circumstances I try to separate them where suitable. However as these things do sometimes come along in a group of problems; be prepared for less than straight forward answers. So knowing I am riding a mildly tuned RD250 E with VM32 carbs TZ250 G expansion chambers and an electronic ignition system lets have a look. Symptoms The bike was on the dyno the day before having recently had a new ignition fitted and was running well with good power and safe temperatures. Engine started well on choke. In the waiting area for the Pembrey practice session; the bikes tick over w...