Ref; 1986 VF500 Hey all, I've been resurrecting this bike from the dead and it's been a fun journey. I finally got it all back together but it's got some cooling issues. I'm not sure if it's because it's so hot here right now (97 degrees today in stop and go traffic) but I would appreciate some input. - I replaced the thermostat with a new one (the old one didn't even open when boiled) - Antifreeze is a 50/50mix of the low metal corrosion type. Also, purified water used in the mix. - Fan is turning on when it's suppose to. - Temperature increases on warm up like it's supposed to and even stays at half way for awhile but once it gets above the half way point it rises rapidly. - Checked oil; no water and no oil in the water. I confirmed that the water is circulating by pinching hoses and watching movement in radiator filler. Any ideas? If I increase the water ratio does that make it run cooler? It doesn't get much below 40 degrees here in the winter so I'm not worried about it freezing up.
They do run hot unless you have good airflow through the radiator. Are your observations from when you are riding the bike?
Take the 50/50 mix out! Glycol retains the heat. Use a product like Water Wetter, distilled water and a little rust inhibitor. Your temps will drop if all else is good. Do not use WW with glycol. It will retain the extra heat the WW extracts. Keep the 50/50 mix for winter storage. I've been doing this in all my performance vehicles for years. It works very good.
Thanks for the input. I did a little research and discovered a BBS for light aircraft where they are using Rotax engines. These aircraft move at slow(er) speeds about the same as you would travel on a bike. A guy did a whole study on various mixtures. He detemined that the best mixture was a 70/30 (water to coolant) ratio. I tried that and "leaned" out the mixture. It runs about 25% cooler now. I'll try Grey750F's suggestion and see what I get. I've always used the Water Wetter in my larger CC bikes and it helps. What's the reason for the rust inhibitor and what type, how much do you use?
