310 heating! any ideas?

[EAT_A_450]

I just put my ESR 310 together and it started heating on me big time after 30 min of riding- boiling out of the reserve. Any Ideas where to start? Here is what I got ESR 310 with a CR ignition, pwk 38 carb jetted 50 pilot and 180 main- I haven't done any plug chops yet but it's running a little flat on top so I don't think it's lean. How would I go about checking the water pump? So many things it could be- if it's not the water pump I have a feeling it may have something to do with the ignition. Any ideas?

[GREENKAW24]

Your ignition timing may be too far advanced or you are in fact too lean, or both. My KX310 was overheating and flat on top when I was using a KX125 ignition and had to advance the timing (which is what you need to do to get the torque back), I advanced it too far and had to bring it back when it was overheating. When you have advanced timing, your bike will want more gas, making it run lean.

[EAT_A_450]

Ok- I checked the flow of the water pump- seems to be working fine- I'm gonna try retarding the ignition. I bumbed the main jet up to 185- definitely rich- did some plug chops as well but still heating. Also I have a dgh needle on the 4th notch from the top. I don't think it's running lean anywhere- started pretty fat. The manual says could be the radiator cap too- any other ideas?

[fulltiltrider]

It can definately be the cap. I would do a plug chop though just to be sure. I also realized, with mine, that a b8es is too hot for this setup. I am running a b9es plug with no problems and better heat marks. Do a plug chop and take some good close up pics of the chop area and your electrode and ground strap. Post em up, we'll help you out

[EAT_A_450]

Yeah- I'm running a b9es .018 gap- has a dark brown 2mm ring with the 185 main jet- a little rich but I wanna leave it rich till I solve the heating problem. All I can figure is the cap or cr ignition is advanced too much- I put the adapter plate right in the middle of the adjusment which RSR said should be a close starting point. I'll probally tweak on it some tomorrow. When it's hot it doesn't start boiling till I cut it off and the water pump stops moving. Maybe it is the cap?- I didn't notice it till I put the 310 and cr ignition on though but I also didn't ride it much when it was a 250.