OK i know there have been alot of mods done for the air cooled 350's, I am wondering where the best place to put a fan to help in the cooling process. I intend to put a squirell cage fan and duct it down but should it be directed on the top/front of the head or front of the cylinder? I know that the top of the cyl. and the head get the hottest due to combustion so I an thinking of placeing it to cover the top half of the cylinder and up. What do you guru's think?

Anything above the exhaust port including the head is where the majority of the heat originates blowing air in front of the cylinder and head would simulate you driving around while your stopped, if you could get the same are at 15 mph as you would get while driving 40 that would be great too.

I am in the process of getting a air flow meter to check the CFM's that the fan is producing, once I get that, I can check the area you are talking about and find out what I need to do from there. I figure if nothing else if I can move air across the cylinder/head when going slow or stopped any amount will help.

Good idea.

The best place or most effective is mounting about a 8" diameter slim automotive fan in front of the Engine where it can blow on the front of the Engine providing good flow to the head and cylinder, this works great for those that do not need their seat pushed back all the way so their is room to mount the fan behind the seat, if you need the seat back all the way then even just blowing air on the head would be a improvement.

Take your 350 for a normal ride when your done and turn off the Engine feel the head radiating off the Engine and head, when your riding on tight trails and stop for a min or so and the Engine is just at idle no air over its just building up heat, the heat is soaking and migrating into the bottom end of the Engine also, I have been on trail rides with 3-5 machines where you end up stopping at the bottom of a large hill and wait your turn as others climb the big hill once you get to the top you stop and wait again for others to make it all that time the Engine is not cooling off.

The 350s were designed for this type of use and abuse but when you start making performance mods anything you do adds more heat to the Engine, even a after market clutch adds more RPM's than normal that's more heat.

Even all stock having air blowing over the Engine under the conditions I listed above IMO is a huge plus.

Make sure the fan you choose is not going to tax your charging system, I would mount the fan switch in a location easy to access maybe next to your left thumb so you can turn the fan off while on a nice long run where you have movement and plenty of air over the Engine, give the charging system a break from the load and allow it to top off the battery, then flip the fan back on when you come to a stop or get into tight trails.

Liquid cooling is really nice because the coolant system acts as a reservoir to move the heat from the critical Engine parts and hold it until that heat can be released through the radiator, not all applications need this more costly complicated system.

Still cant figure out why Honda never made the Engine fan cooled or added a electric fan that was thermostatically controlled to the 350, slightly modified 250's had over heating problems from day one they had to see this coming, arrogance maybe? the 250 used a motorcycle Engine parts with little to no cooling fins they worked perfect on a cycle where it was put right into the air flow all the time, the 350 they added WAY MORE cooling fins and larger fins than most normal air cooled engines had, they also added air scoops to force more air into the Engine compartment, figured this was good enough? and probably was for a all stock 350.

Document what you do post pics if you can please.

Good info, I will post some pics and as much information as I can get together as soon as I can. I am also thinking about making a a semi air duct behind the seat to push more air while moveing. I am 6'-2" and need the seat back all of the way but there is room to make a air shoot behind the cage to catch more air while moving. then when going slow or stopped turn on the fan. I checked the fan motor (( Internal Combustion Engine ? )) and it is pulling 1.38 amp on start up and then drops to .865 amp run load amp so that will help also.

I had a Honda 350 rancher that had an oil cooler with a small electric fan. It rarely came on, but was really comforting to know that it would when the Engine reached a certain temp. if you could find that size fan for the 350R it would be perfect.. but I am sure they are expensive.

Here is where I added the fan on the side by side. It blows directly above the exhaust bridge & over the head. IMO it made it a big difference on it.

Ok I finally got some pics of the cooling fan that I made. It looks rough but paint will (help) on that. I will get the amp draw and cfm's or velocity tomorrow I hope. I have it blowing across the front of the head and then off of the back of the seat to the cylinder and head. I will find out how much it cools it down also, and how long it takes.

That's a manly fan! You may need a deep cycle battery on board to run that sucker a lot.

Not at all, I run it alot and have never had any problems "YET" But it works good and has a small amp draw. I am going to check it again and put the #'s on here. Just haven't had the chance yet. I work out of town all week. Thanks Billy