Originally Posted by Genghis Dylan Sincléir
Hey people, I joined the website because i'm fixing up a 94' mc22. So far i've been learning a lot. I've changed the starter motor, spark plugs, clutch cable, oil & filter etc. i love the bike it's something else. It sounds like a dream, however like most things, it has problems. I was wondering of anyone could help me with;
1) overheating issue( I hear overheating is quite common in mc22's) however, my girlfriends dad is a mechanic and he quickly looked at the radiator and said all the pipes are good and the coolant is a nice colour, could it be the thermostat?
2) my low beam lights are working with both bulbs, however when i turn on high beam, it doesn't work. I've gone through all the fuses and wires and they're all good, does this mean it's a bulb replacement?
thanks for your time and have a wicked day/night
Overheating could be the thermostat. How quickly and under what conditions does it overheat? Does it overheat very quickly, or does it take a good bit of riding to overheat it? Quick overheating could be as simple as an air bubble in the cooling system, and would be solved by bleeding the system. A stuck closed thermostat could also cause quick overheating, but it is simple and easy to bleed the system and rule one thing out. If it takes longer to overheat, then diagnosis gets more difficult. Try taking a garden hose and spraying the radiator with pressurized water from the engine side towards the fender, that should help clear up any debris stuck in the fins blocking airflow. Worst case would be that your water pump fins are eroded and not pushing enough water to cool the engine.
Try cheaper things first if you are unable to diagnose the overheating issue. A coolant flush and fresh honda motorcycle coolant is not expensive at all. I had to flush the coolant in my VFR 400 to get the old rusty water out, looks great now. It should also be mentioned that the new coolant collected rust that had not been previously removed. The rust settled to the bottom of the container I used to collect the coolant when I was changing out thermostat gaskets. No more signs of rust after that!
You might try messaging Das Chicken; his initial post is 5 below yours. He also has a cbr250rr and a bit of repair/maintenance experience with it.
As I recall, checking the thermostat requires removing it and putting in a pot of water that is heated until (hopefully) the thermostat opens and you can measure the water temperature.
Could the lighting thing be as simple as having rotated a connector so that the "high" beam comes on as the low beam? It sounds like something where the single bulb (I am assuming that this is the low beams setting) isn't being turned on by either light switch position, but that that lamp lights when both bulbs come on in your "low beam" setting.
Close, very similar bike but mine is still not a 250rr, its a single R.
My MC19 uses dual filament bulbs for the headlights, so it could just be that both high beam filaments are severed. OP, you can pull the bulbs and look into them, each filament is a tiny tungsten coil, if the coil has a small break in it, then it may not light up. If you shake the bulb and see a coil wiggling around that would be a dead giveaway for a bad bulb. Try new bulbs.