electric fan-cooling for air-cooled motors

Discussion in 'Rack Mounted Engines' started by JemmaUK, Oct 7, 2007.

  1. JemmaUK

    JemmaUK Guest


    Has anyone considered whipping that blower thing off the side of the zenoah type engines and replaceing it with an electric blower fan run off a battery and fed off a dynamo from either front or back wheel?

    It would surely be quieter than the engine driven fan and would possibly be more effective using such fans as those used for PC power supplies. Using the battery would mean that the engine is still cooled when standing still..

    I am going to try some night rides to see if I need to make improvements to the bike... and get used to that front fork..

    Jemma xx

  2. PC fans may not push enough CFM to keep the motor cool at slow speed/idle....How about a gas powered leaf blower with some custom ducting....could be run off the same fuel too.
    You could rig it for faster blower speeds when the drive engine is at idle or low throttle and have the blower reduce speed as the main drive engine increases speed (because as the main engine increases speed I will assume the air from the bike motion would cool it off)...

  3. Jim H

    Jim H Guest

    Kind of defeats the purpose of such a simple yet effective system as the zenoah or tanaka or robin/subaru. Add more weight with battery and fan and shrouding and you have a scooter. I love scooters as well but I also love motored bikes.:cool:
  4. dbigkahunna

    dbigkahunna Guest

    I agree. Why complicate something. Out here in Gods country, it gets chingles hot and the factory cooling on my engine works great. Even at low speeds.
    Last edited by a moderator: Oct 14, 2007
  5. Alaskavan

    Alaskavan Guest

    Fan cooling system

    The project I'm working on includes having the engine in an enclosed space (3 sides). I figure that at speed, there will be adequate airflow for cooling, but I am concerned about when it's sitting still. 12v power will be available, so I was figuring to incorporate a fan from a small car heating unit.Maybe just switch it on when I anticipate leaving it running while sitting still.
  6. 5-7HEAVEN

    5-7HEAVEN Guest

  7. Alaskavan

    Alaskavan Guest

    I should perhaps have mentioned that the engine I'm using in my next project doesn't come with a fan.


    And it doesn't belong in Rack 'Em Up. Sorry 'bout that.
    Last edited by a moderator: Oct 17, 2007
  8. JemmaUK

    JemmaUK Guest

    I was only speculating really - but since you say - what I have is effectively a tall scooter anyways. Given the performance increases Anita is probably equal in performance, if possibly not power, to a JDL powered cyclemotor. The point being that the fan on the engine isnt quiet and I prefer the engine to be fairly quiet... and the PSU fans on any computer would be more than enough to cool that engine - ie one on either side.

    My problem with the zenoah is I am worried that it will end up having the same issues as happened with, for example, the early aircooled centreline thrust arrangements - one engine gets lots of happy cold-airness and the other one gets cooked and you get all that nice blue smoke so beloved of second world war films... (incidentally, who sold the germans all those Merlins?!?). By that I mean that one side of the motor gets nicely cooled and the other gets less - I *always* get a ticking from the exhaust side after a longish run... which is the hot side... so I was looking for more balanced cooling..

    Jemma xx
  9. craisin

    craisin Member

    if you run an airbox you may not hear the ticking anymore.

    If you wanted to make one out of a plastic bottle just to see if it ran quieter and if it was quieter you could make a better one

    And an airbox will stop the rain from swamping your engine on a wet day