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Post by Fokus on Nov 14, 2011 22:03:23 GMT -5
All goes back to one thing, driving conditions and needs? Drive in the heat with high humidity and expect to run for the long haul leave the OEM fan alone and let the engine stay it's coolest and keep it in the desired running range along with good maintenace and expect a longer lived dependable engine.
Want to run it at high RPM's reduce the fan cooling and run in hot enviroments then expect to have a short lived engine experience.
Riding in cooler places one can get away with it more but as with many engines especially air cooled heat is a enemy and with higher RPM's for more HP heat is a factor no way around it.
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Post by Pony66 on Nov 25, 2011 16:50:35 GMT -5
I have been playing with my fan again. I put a red LED in the Timing mark access window. It worked great until it touched the fan. It made the chrome fan reflect red light. I will solder another LED in there cause I want to see it at night.
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Post by fleetingyouth on Dec 3, 2011 22:11:57 GMT -5
Just curious how well this mod holds up in bad weather? Would it cause more rain to get in there and would that have a bad effect? I assume it would.
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Post by mainepeace on Dec 3, 2011 22:28:47 GMT -5
The fan just blows air around the case and cylinder. It's not an intake for anything else, so there shouldn't be any issue other than possibly some corrosion on the outside of the case. Assuming the seals don't leak. As long as there is a drain hole and water doesn't accumulate at the bottom, there is little risk that I can see.
Greg
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Post by imnts2 on Dec 4, 2011 10:14:59 GMT -5
The problem with this type of fan (squirrel cage) is that they are easy to stall. An axial fan will deliver a lot more pressure and thus will force air though the baffles while a centrifical fan will move a lot of air if there is little restriction to its movement. I am not sure how reducing the the fan blade area will effect the air flow thru all baffles that surround the engine. I certainly understand how lightening the rotating mass will improve throttle response. After all we have been lightening flywheels for years to get lower times on the drag strip. But I am more concerned about cooling and maintaining a decent cruise speed over more extended distances than how short the fuse it. I wonder if there is a good and relatively inexpensive way to get cylinder head temperature reading to test some of these mods a little more accurately. It would be nice for it to be accurate enough so we can talk about it with reasonably believable. Yoy would think we could fairly accurate speed readings but I have little confidence that evryone is always nearly accurate. I am less sure of many seat of the pants jugement of performance increase. I just think that things that work on thedrag strip ofter are not usefull cruising about town. Cheers lefty2
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Post by larry001964 on Dec 4, 2011 10:21:23 GMT -5
Actually I'm very interested in this thread, I really don't know much about these fans efficiency, but I em wondering if the heated air can be routed into a body suit to provide heat.. Winter driving.. It's just an idea i got while i was rebuilding my engine, and looking at the cooling shroud..
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Post by mainepeace on Dec 4, 2011 22:16:52 GMT -5
Someone posted about running a water tube around the exhaust to the seat to provide a bun warmer. I don't see why it wouldn't work.
I'm sure that if you really wanted to you could look into making some custom vents that would route air from the side fairings directly into the engine bay. The vent openings would have to be in the airstream, so the best location would probably be on either side just behind the front tire, right where the water spray would hit when going through a puddle. The center of the front fascia (just above the front fender) has a higher pressure zone, but there is a longer distance for the air to travel down the duct, minimizing it's efficiency.
Have a vent on either side routed through the floorboard under each foot that would converge just at the cylinder valve cover. A new cover replacing the current engine cover would have to be made, routing the exhaust from the case out the back. An impeller style fan could be inserted into the ductwork to flow air at low speeds in traffic. It should work really well as a positive pressure system, except for the need to filter out road debris and small animals, and to have a low spot in the system for water to drain.
Greg
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Post by momule on Jan 16, 2012 0:33:21 GMT -5
25% hp gains? surely sir, you jest at best....
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Post by Pony66 on Jan 16, 2012 9:41:05 GMT -5
25% hp gains? surely sir, you jest at best.... Yes a jest but not the best
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Post by evilgenious on Feb 7, 2012 0:15:44 GMT -5
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Post by TERRA NUVO on Feb 7, 2012 11:56:05 GMT -5
evil you surprise me, as i know you 're smarter then me. FAN SCOOPS DON'T WORK AT ALL.NONE,,,ZIP...0
air in take is at once increased and limited to the speed of the fan, same thing that brings air in, stops and limits its intake.
many many many air conditioning guys have tried to increase CFM's cubic feet per minute with a fan, intuitively great idea, in action, does not work, and in the case of a extra motor actually heats up the air.
best thing you can do is take out greats or get better fins, the latter being hard over stock on most bikes.
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Post by Pony66 on Feb 7, 2012 12:51:49 GMT -5
evil you surprise me, as i know you 're smarter then me. FAN SCOOPS DON'T WORK AT ALL.NONE,,,ZIP...0
air in take is at once increased and limited to the speed of the fan, same thing that brings air in, stops and limits its intake.
many many many air conditioning guys have tried to increase CFM's cubic feet per minute with a fan, intuitively great idea, in action, does not work, and in the case of a extra motor actually heats up the air.
best thing you can do is take out greats or get better fins, the latter being hard over stock on most bikes.I think the scoops look cool(another pun). I dont know if they increase, decrease or have no effect on air flow. I would think about a scoop for style, but I went another route. To throw a log on the fire: IF it does increase airflow, the fan would work less for the same airflow. So It could, in theory, free up some drag on the engine.
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Post by D-cat on Feb 7, 2012 23:34:19 GMT -5
You think a scoop increases air flow? Try this experiment: while going down the highway in your cage with the window open, stick your head out the window facing the oncoming wind, open your mouth wide, and try to breathe in. (There's also no reason you can't do this with your bike as long as you can get a good speed going and you're not wearing a full-face helmet)
The fact is splitting the air causes a negative pressure region that can potentially slow the air flow down if anything. TN is right, just I believe for a different reason.
You do want to get as much air through as possible since it can make a difference considering the temperature difference, at least to a point. Thermal transfer is a slow process so yes, once you have reached a certain air velocity adding more doesn't make a whole heck of a lot of difference, however with these air cooled engines I'd rather risk having too much than not enough. The air scoop though I do not believe to be a functional idea to accomplish that task (though they do look cool).
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Post by ace420srh on Mar 29, 2012 21:27:54 GMT -5
here is what i did... I started with abs 90deg 3in street elbow cut it. shaped it. added protective screen and removed the horizontal and vertical blades. plastic welded it together and bam! crazy airflow over stock and it has no fan mods yet.
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Post by timelancer on Apr 30, 2012 22:37:12 GMT -5
Sorry not to shoot you down d-cat, but RAM air intakes were used on just about every muscle car to increase airflow to the engine, they do work only problem is that they only work after 55mph, which is slightly out of the scope of most 50cc tuners. I think it would help just for the simple fact that it wouldn't allow the air scoop to draw in the hot air from the exhaust pipe. Then again muffler wrap could do the same thing, either way my scoot is doing 60mph+ right now and overheats badly after a ten mile run. the theory that the airscoop would add power by reducing drag on the FAN is a good idea, but it will add drag to the BIKE therefore nullifying any power gain and possibly slowing you down.
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Post by tortoise on May 1, 2012 8:36:56 GMT -5
Temperature meter resource. For what it's worth . . based on the images, the two Genuine Buddy 125 scooters that completed Scooter Cannonball Run 2012 used the original air cooling configuration which draws air through the fan-cover bottom directly above the exhaust pipe. One Buddy 125 did require a replacement stator, but the other made it with only routine maintenance. That Scooter GuyBSFF
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Post by revweasel on May 1, 2012 8:46:14 GMT -5
Very interesting reading... the French... op on the front fascia? A really adventurous person could make a custom jug that has passages for water cooling welded onto the fins. It actually wouldn't be *THAT* hard to do. Just cut off the fins and solder on copper piping that circles the jug, then fill in the spaces with some more liquid copper to create a good heat sink. Greg drill holes through the fins, install copper or aluminum tubes into those holes, plumb together in some sort of parallel configuration so that cooled water will flow through and go to a heat sink. even easier, wrap some flexable copper tubing around the engine between the fins, notch the fins to the tubing can climb so the next step. perhaps with that sort of configuration you could get convecton flow through the heat exchanger.
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