Well, to paraphrase Tiger Woods, "Hello VFR World!!" Last summer I purchased a 2007 VFR from a local used bike dealer with 24K on the clock. The bike is Candy Red with a Two Brothers 4-into-1 can (very fruity, indeed!). I've added ASV unbreakable levers, a Sargent seat, Laminar Lip, LightTech Frame Sliders and a colour-matched rear hugger from Great Britain. This bike is dedicated to my Washington, D/C., duty station but I also have an Ash Grey 2003 Aprilia Futura at my permanent residence in Phoenix, AZ. I love the VFR but for one comment/observation. It runs too damn hot!! I've perused the other forums and discussions on this site and understand that VFR's run unusually warm due to engine configuration/layout/design. However, it seems to me that an engine that routinely runs into the 240's/250's is inherently flawed. I noticed the problem shortly after purchase and the mechanic (not Honda trained) drained the coolant and added Water Wetter and Synth oil with an instruction to run a gear higher than usual when cruising around (5k-6k). This provided a short-term, if unsatisfying fix, for the time being. However, it was more than a little frustrating to not be able to run the bike in the meat of the powerband where the VTEC kicks in without risking overheating. I mean, what's the use of having VTEC if you can't use it!? I took the bike to Honda experts for a solution when it became apparent that the Water Wetter wasn't addressing the issue. The bike passed a tech inspection and the radiator cap maintained pressure, the water pump is functioning, the thermostat is working, etc. They then changed out and freshened the synthetic oil and added Honda coolant back to the system but the bike will still run into the high 240's in certain conditions which raises the central question of this post. Is there something unique about the VFR cooling system that would make it run hot in humid conditions? My armchair observation is that on exceptionally warm, muggy days in D.C. (80+ degrees @ 70% humidity) the bike tends to run very hot, especially in local street riding or in traffic. Now, I've ridden my Aprilia through the Sonoran and Mojave deserts in temps. up to 118 degrees and I have never had the bike run hotter than 229 degrees. I understand different engine layouts and radiator positioning and all but I'm just sayin'. I'd be interested in other owner's experiences, particularly those who reside in the hot muggy sections of the country (Miami, Houston, New Orleans, Atlanta, St. Louis, etc.) Thanks for any insight or perspectives that you may have.
First :welcome: to the madness :wave: Second the VFR tent to run a bit hotter than other but I have not seen any 6th gen would go up to 240 degree and everything check fine When i ride in a hot summer 90 or 100 the temperature can get up to 235 and it would drop when I pick up the speed. This has been discus lately, let see what other say.
That's too hot. All vfrs run hot but that is too much. To address your question about why they run hot, the whole side radiator thing is a bad idea. the radiator fan draws air from the out side across the radiators to cool the bike down while your stuck in traffic. This works.... ehhh adequately but if you are on the highway with the fan on you are fucked. The direction of the air that the fan is drawing in is opposing the direction of the air that the bike is pushing through. While the fan helps while you are stuck in traffic, it actually blocks airflow while you're moving. There are a few things that you can do to help. Get a catless header and ceramic coat it or wrap it to block exhaust heat from saturating the engine bay. Install a power commander and a richer map. The extra lean map that these bikes come with from the factory make more heat. Another thing is install a manual fan switch. This means be proactive about the heat. I turn on the fan when ever I am moving less than 40 mph and the bike is over 180 degrees. I try to stay ahead of the heat, to not let the bike get a chance to heat up. Also if I know I am going to be at a stop light for more than a minute I just turn the bike off. Doing all the above, I rarely see over 200. Also, start researching vfr charging issues... lol
If your bike is reaching 240 degrees, it seems to me your fan is not working. It should kick on somewhere between 221-225 and bring the bike temp down. If the fan IS working, I would say you have a thermostat that is not opening all the way. In my 5th gen, I replaced the coolant with Engine ice and it helps. In really hot humid weather (like 90ish), depending on wind direction, my bike can sit at 200 degrees, even on the highway.....But it never goes above 225 before the fan brings it down in stop and go city driving. Something is up with your bike.....
If it were my bike, I would flush the cooling system - use the white vinegar trick to clean any scale out of the system (search the site for the best procedure to do this). Make sure that your thermostat is opening, and replace the coolant with engine ice or use Honda coolant with water wetter or similar. Check to make sure your fan is kicking on at around 220-225, check to make sure the fins on the radiators are clean, and that none of the rubber coolant hoses are pinched. My bike has yet to go over 230 in traffic, 100+ degrees and humid. Just my $0.02. YMMV. :thumb:
