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voodoochikin04
09-12-2007, 03:41 AM
i didnt wanna hijack the other thread.. *but is it a bad thing to use an air cooled engine? *i have a 95 suzuki gsx600f/katana. its air/oil cooled. am i gonna run into problems? and is there many others using these types of engines? * -MATT

PilotHawK
09-12-2007, 06:49 AM
Air cooling should be fine as long as you ensure that you have adequate air getting to the engine. The honda FL350 is air cooled and works great. Honda uses air deflectors to increase airflow to the engine. Some people with modified engines in their 350's have added fans too.

One thing you can do with "air cooled/oil cooled" engines is use a larger oil cooler that is exposed to good airflow. I plan on using a 400ex motor in my buggy and it is air cooled. The primary thing I plan on using to help cool the motor is the addition of a large oil cooler.

On air cooled engines you can make them run cooler by 1) decreasing the temperature of the air around the motor: header wraps, 2) *increase the amount of air getting to the motor: fans or air scoops, 3) Increase the surface area that is available for cooling: aftermarket head, larger oil cooler.

If you find that your engine is getting hot in stock form there are options out there to help cool the motor.

Rorty
09-12-2007, 07:10 AM
The honda FL350 is air cooled and works great.

Yes, but Honda designed it to be plonked behind the driver's seat from the beginning, whereas an air-cooled bike engine is designed to be up front in the air flow.

You can run an air-cooled motor in a buggy of course, but as PilotHawK says, give it a fighting chance. I personally wouldn't choose to run a toaster because keeping them cool enough is a bit of a hit and miss afair and I've seen too many of them completely fry.

But, if you have a toaster sitting there doing nothing, then why not give it a go - you'll get damn all for it if you try and sell it and if it fries, go and buy a kettle engine then.

greentowtruck
09-15-2007, 12:15 PM
well looks like there are two of us matts going to run air cooled engines. I have about 4 of these kz 1000 motors sittting here so i figured why not try it

plkracer
09-15-2007, 12:32 PM
Use a large oil cooler with a fan. The street bike engines don't have large fins like most off road engines, because they are made to be run at higher speeds. If you can, make some wide scoops on the sides of the seat, and point them at the engine. Try to monitor oil or cylinder head temps to avoid a meltdown. I have a fan on my 400ex's oil cooler, but the engine will still get hot in the sand. I couldn't imagine it in stock form with a heavier buggy.

K-fab
09-15-2007, 02:05 PM
Another option is to have a couple fans that blow air over the heads and cooling fins too. *I know of a couple 350 Oddy guys that do this and it seems to work quite well.

Look into the Spal brand for fans. *They make some high CFM fans that are fairly small and light weight.

You might consider a pair of these with some sort of shrouding to control the air flow to/over the engine instead of just an open blow from the fan towards the engine. *Some sort of intake or draw from the sides of the buggy, say just behind the seat would probably work fairly well.

plkracer
09-15-2007, 02:39 PM
Put a huge air scoop behind your helmet *like the indy cars have. Tell everyone it's a ram air. Lol Kfab, where do they sell the spal fans? How much more cfm do they produce, and do they require more amperage? I would suppose so, unless they have more efficient blades/ motors.

K-fab
09-15-2007, 06:46 PM
Where to get the fan...
Try some of the off road warehouses and, for that matter, places like Summit too.

McKenzie's sells Spal, Fluidyne, Setrab, Perma-Cool and Derale fans.

If you go to [url=http://www.mckenzies.com:vsbncg5n]McKenzie's web site[/url:vsbncg5n] and open up the stupid PDF file (the things suck) that they have for a catalog go to pages 84 & 85 of the catalog - not sure what pages those are in the PDF file - you'll see a wide variety of fans.

Spal are on page 85 and they list sizes from 6.5 to 16", both push and pull. *Strange - they list them all by size, direction and weight, but only list two of them by CFM - 13" 1710 CFM and 16" 1610 CFM. *Both of these are pullers.

A lot of the Spal fans use curved blades and are supposed to be quite efficient. *I don't know how much more or better they are than some of the other brands - it's just what I've been used to using - it's what ATV puts on the Tazcars. *Being that McKenzie's has almost an entire page dedicated to Spal and all the other brands I listed above are on one page, I'm guessing that Spal's one of the more popular units and must come in more sizes and variations.

I would imagine that Spal has a web site, but I'm too lazy to go look it up. *[smilie=loser.gif] *<--- me!

nutnbolt2002
09-15-2007, 07:51 PM
Kfab do you think that a car 12" pusher fan mounted fairly close to the engine work good enough, with a little bit of fairing?

K-fab
09-15-2007, 08:34 PM
I can't really say... *It would be all about getting as much CFM as you can.

If nothing else, it's a good start.

voodoochikin04
09-21-2007, 10:24 PM
how would i go about monitoring head temp? *infared thermometer? *also.. could i get a couple bike rad fans and mount then on the fins, *also having air ducts from around the seats? *and i like the idea of an air scoop on top.. *might look ok.. * *the oil cooler it has on it.. *is about 12 x 7 inches.. would that be sufficient with a fan or two? * *"you guys have me all worried now"

greasemnky
09-21-2007, 10:49 PM
Main problem with air cooled, shut it down when your stopped!!! People tend to pull over and chat or rest with their stuff running, that will over heat an air cooled motor really fast. Only time I melted my moded blaster, was leaving it idol after a pretty hard ride.

On my old FL350, I mounted a cheap 12in autolite fan to blow down on top of it (17 bucks shipped on ebay), and it never over heated. Theres a guy named ramjet who made a great looking fan out of a speaker grate, worked fantastic. What type of area will you be riding in?? That plays a big factor. Slow trail riding is bad with an air cooled. More open fire roads, or even light duning they work fine. Also, the temp you ride in matters. My friend runs an air cooled 440, and we try not to ride on 80+ days. * Being in nebraska, I think you'll be fine. Plus if you already have the motor, worse come to worse, you blow it up, and buy a liquid cooled. Important thing is to build something. You'll outgrow your first one pretty fast. You'll love it, or give up on it.

Rorty
09-21-2007, 11:08 PM
Main problem with air cooled, shut it down when your stopped!!! People tend to pull over and chat or rest with their stuff running, that will over heat an air cooled motor really fast.

The trick (whether air or water-cooled) is to have the fan on a thermostatic switch, but run it live (not through the ignition switch) so that when the engine is shut down, the fan will continue to work (if necessary) until the engine has cooled down sufficiently. Then you can turn all the electrics off at the master switch.

A 12" x 7" oil cooler is fine for a bike where the engine's up front in the air stream, but I would recommend doubling that size and installing a thermostat in the oil lines too.

boilermaker
09-22-2007, 02:20 AM
You can drill and tap a hole in a fin on the head , then install a temp. sending unit if you want.

greasemnky
09-22-2007, 07:12 AM
I just had mine wired to a toggle. Is there a problem with running it all the time?

Gene
09-22-2007, 09:55 AM
You could also monitor exhaust gas temperature as useful feedback. I've seen this done on several Banshees so they can jet correctly.

voodoochikin04
09-22-2007, 10:50 AM
man you guys have me all worried this motor is gonna keel over.. * the guy i bought it from has an old sled engine on his giat heavy buggy.. it has a belt drive fan blowing over the fins.. he said he never has problems with it overheating.. it have virtually no direct airflow.. *are they just built to take that abuse or what..lol

greasemnky
09-22-2007, 08:25 PM
The average guy isn't out pounding on their buggies all the time. As long as you watch how you run it, use common sense and don't ride if its 100 out, and throw a fan on it, you'll be fine. If it was going to be raced or something, thats another story. But theres 100's of air cooled odysseys running around, air cooled 440's etc. Is liquid cooled better, well duh. But an air cooled motor isn't going to grenade in the first 20 minutes if you just use your head. You'll be fine. One of jays starter buggies ran a kawasaki 650 air cooled, never had any trouble with it what so ever. I think the sled motors are more prone to melt downs, since they were made to be run in the cold. With a bike motor, you'll be fine.

voodoochikin04
09-23-2007, 01:13 AM
would a radiator shop be able to connect two oil coolers together?

Gene
09-23-2007, 10:42 AM
You should be able to have a simple hose made with fittings to link them together. Try a shop that makes hydraulic hoses.

nutz4sand
09-23-2007, 12:42 PM
Aside from more oil cooling of a bigger or added oil radiator an extra outside oil reservior is also a help adding volume and cooling if the reservior is finned. Do not forget that if you move a lot of air into the motor area it helps to remember to move the hot air out. I have seen buggies with panels that restricted the air out the the big scoops brought in. Aircooled sled motors do fine if they are not pushing to much weight and are geared correctly. A two strokes RPMS are as important as anything when it come to cooling them as the air thru the motor internals take away much heat. The rpms it was built to run at make sure there is a good flow of air thru its guts to facilitate this. The streetbike motor should be OK if there is an airflow hitting the motor where ever you can and especiallly where the fins are that draw the heat out of the internals. It would not hurt to even fab a scoop to take air to to the backside of a bigger four cylinder and blow it at the backside of the cylinders in the middle thru a pipe from the scoop. Some motors I have seen have room and fins under the carbs there and any air movement is good. Bill

voodoochikin04
09-23-2007, 05:01 PM
thatnks for all the ideas guys.. :)

plkracer
10-05-2007, 07:00 PM
Main problem with air cooled, shut it down when your stopped!!! People tend to pull over and chat or rest with their stuff running, that will over heat an air cooled motor really fast. Only time I melted my moded blaster, was leaving it idol after a pretty hard ride.

On my old FL350, I mounted a cheap 12in autolite fan to blow down on top of it (17 bucks shipped on ebay), and it never over heated. Theres a guy named ramjet who made a great looking fan out of a speaker grate, worked fantastic. What type of area will you be riding in?? That plays a big factor. Slow trail riding is bad with an air cooled. More open fire roads, or even light duning they work fine. Also, the temp you ride in matters. My friend runs an air cooled 440, and we try not to ride on 80+ days. * Being in nebraska, I think you'll be fine. Plus if you already have the motor, worse come to worse, you blow it up, and buy a liquid cooled. Important thing is to build something. You'll outgrow your first one pretty fast. You'll love it, or give up on it.
After a hard ride, you should just run around too cool it down, or leave your fan on. i've had my 110 fry because i ran it really hard, then shut it off. The heat just built up into the head. Must have come from the piston or something, but it fried the rings.