I changed my coolant on the weekend. According to the records I had for the bike (mainly date of purchase) it was coming on two years old and so due (if not overdue) for a change. Having been ripped off only a few months ago for my 6,000km service by a Suzuki dealer located in the Springwood area, I decided that I will be doing all this basic level of serving myself. Your service manual will have all the information you need, but sometimes some real pictures and an explanation help more. If you have a v-twin or L-twin I would suggest you dig around on the internet for some information on how to change the coolant on your particular bike because I have it on good authority that those engine configurations are harder to bleed the air out of and are prone to developing air-locks. If you have an RGV250, get a mechanic to do it. What I used: 1. bike service manual; 2. 15 litres of de-ionised water; 3. undiluted coolant for use in aluminium radiators (1.5 litres); 4. large empty plastic container (to catch coolant on the way out); 5. measuring jug to measure coolant in and out; 6. funnel; 7. pieces of towel for any spills; 8. socket set, phillips head screw driver; 9. 1 beer. How to do it: First up, take off the radiator cap and undo the hose clap connecting the lowest hose to the water/coolant pump. Lowest hose for obvious reasons. Coolant will splash out a bit so have a big container at the ready and make sure the engine is cold. If it is hot, the fluid will be hot (I can't believe I have to type that, but I feel I do). Put down some towels or newspaper. Wear gloves and goggles. You don't want any of this stuff in your eye, hospital emergency departments are expensive and slow. Let all the fluid drain out. While this was draining I disconnected the reservoir and drained it. I then took it off the bike totally and gave it a good wash out, stuck it back on and connected it up (empty). Once all the fluid is out, bolt the hose back onto the water pump. Measure how much fluid just came out (of both the radiator and the reservoir). My service manual says my radiator capacity is 2.4L. I only got 2.35L out of it. The amount in the reservoir is kind of irrelevant due to upper and lower lines. Service manuals are not always spot on correct so you want to know how much you need to get back in the radiator before you ride. Then fill radiator up with deionised water. I put in about 2.2 L and it was up at the top of the radiator inlet. When filling (with water or coolant depending on the step) its handy to have a mate hold the bike and lean it right over to the stand side making the radiator inlet the highest point (considerably). This has the obvious benefit of meaning that there is less likely to be air trapped somewhere in the system. I have no mates so I couldn't do this. I rocked the bike side to side (as per the service manual) and squeezed all the hoses. The fluid dropped considerably and I put the other 200ml in (total of around 2.4L give or take the odd drop that spilled out when rocking the bike. The radiator was full up with de-ionised water. With the radiator cap off, I turned the bike on and let it heat up to about 85 degrees. All the while, rocking the bike side to side gently and squeezing hoses. Top up with more water if you see the level drop, it may well do when the water starts circulating and any air gets burped out. I turned the bike off and waited for the bike to cool a little. Again, if the bike's display says the engine is at 85 degrees, I think its a safe assumption that the fluid in it is too. So don't undo any hose clamps until it cools down. And/or wear gloves (I am impatient and so wore gloves). Undo the same hose as at the beginning, noting the same points in relation to temperature of fluid and the fact that it will probably splash everywhere. It was still really dark green. Repeat the above process. Still green, but getting there. Finally I settle on this. I probably could have done one more flush through. Now I mixed up my coolant 50/50 with the remaining de-ionised water. Check your service manual for appropriate types of coolant and recommended mixing ratios. Fill up the radiator again putting in about 2.2L, rocking the bike and squeezing hoses, top up the radiator to full and start the bike. Once started, rock and squeeze some more, this time I let it heat up to 90 degrees (some fluid bubbled out of the radiator, remember the cap is never on for any of this). I turned off the bike and let it stand for a bit. At this stage I cracked the bleeder bolt (located just above the metal knob sticking out of the water pump) and a bit of air fizzed out and then fluid started dripping out. I closed it again and tightened it up (not too tight as it has a crush washer and you don't want to split the metal water pump). Topped up the radiator again (hardly needed any it was almost overflowing) and placed the cap back on. Then I filled the reservoir to the upper line. I wiped the tyre (note the coolant that splashed on it during burping procedure). I geared up and went for a squirt around the neighbourhood (with fairings off in case I had to do anything else). I rode for 10 -15 minutes and got the temperature up there to 80 - 90. There wasn't much traffic so it didn't get up to 100 or over (as the GSX-R will do after being in traffic or dirty air for any more than 2 minutes). Rode back home and left it run for a bit. All levels still as is. Turned off the bike and did some other stuff. Came back a few hours later and the reservoir had dropped slightly (really slightly) so I topped that off. I opened the radiator cap again (bike is cold remember or else fuild sprays you in the face and you die) and it was still full. So closed it, patted myself on the back and so forth. And that's it. Total cost to me was maybe $25 and an hour or so and I know the job was done and done right.