head and cylinder temperature.

Discussion in 'Whizzer Motorized Bicycles' started by august, Feb 6, 2009.

  1. august

    august Member

    Has anyone ever checked the temperature of the head and cylinder of the Whizzer engine when running and fully up to operating temperature?

    I figured someone might have one of those temp. sensing devices.

    I am making a block to isolate the carburetor from the heat of the engine, but need to know how much heat the block material will have to withstand.

    Thanks August

  2. Mountainman

    Mountainman Active Member

    I think that Quenton here on site may be able to help you with this question

    doesn't seem like any added protection there should be needed
    usually one can touch a carb and to the touch it's not that hot while running even hard

    just an idea if that's trully what you wish to do
    a shield made of thin tin should be fine
    making sure that to one's best not to restrict air flow around the jug

    ride that thing
  3. RdKryton

    RdKryton Active Member

    Hi August
    I am pretty sure you will see temps approaching 500 degrees F on an NE5. If modified it can go higher. Whizzer offers an aluminum spacer complete with longer studs however it is too thick. Best results have been found by cutting it down to 1/2" or 5/8" thick. Mine is at 1/2" thick and I don't have any fuel boiling problems and my engine is modified.

  4. Quenton Guenther

    Quenton Guenther Motored Bikes Sponsor

    Hi August,
    An NE motor with the cylinder painted black [cylinder paint], and a copper head gasket should give you head tempatures of 525 degrees. A stock NE with a steel head gasket can reach as high as 625 degrees.
    The aluminum manifold kit will easily keep the gas from boiling, but works best at 1/2".

    Now if you are refering to a NE-r, all bets are off. From the looks of the head with less fins, and the fact that the top of the motor is tucked under the 2 side covers, I would guess it might run a little hotter, and I wouldn't sit around at idle for long periods of time.

    This post isn't to intended to "bash" any company, person, persons, or vendor.
    Have fun,
  5. august

    august Member

    Thanks for the replies.

    Mine is the NE R, and I do have the 1 inch thick aluminum spacer , and it has one bakelite type gasket next to the cylinder, and also one between the carb and the spacer. The one time I had it running for a while, when I came back to the shop, and parked the bike, after a couple of minutes, fuel was dripping out the back of the carb. I checked the float level, it is correct.

    The carb was too hot to touch. It was hard to start again, because of the fuel boiling I think, and causing flooding.

    A question, why would making the block thinner make the carb cooler? I would think that having it thicker would give more material to dissipate the heat before it reaches the carb.

    I have some phenolic material, it is rated for four hundred degrees, I would hope that the cylinder temp at the carb would not get much over that.

    Regards August
  6. RdKryton

    RdKryton Active Member

    I don't think the smaller aluminum spacer would make it cooler. I think you are dealing with higher temps to begin with because of less cooling fins on the head. My experience is with the NE5 not the NE-R.

    Last edited: Feb 6, 2009
  7. Quenton Guenther

    Quenton Guenther Motored Bikes Sponsor

    Hi August,

    I don't think making the manifold shorter would reduce the carburetor tempature.

    But I suspect your motor will run a lot hotter, and will need the entire length of the aluminum spacer.

    I can tell you a way that might help cool the NE-r carburetor down. Make a "cooler" for the carburetor. Take a 2" square piece of material [aluminum, bakelite, phenolic] 1/4" thick and install in the upright position between the carburetor and the manifold. This would be like installing a large fin to help cool the intake path. I used this method on the early 26 MM carburetor, I was able to bolt the carburetor directly to the cylinder and had the "cooler" as a spacer between the carburetor & cylinder.

    Have fun,

    Attached Files:

    Last edited: Feb 6, 2009
  8. august

    august Member

    I will try the fin idea, in addition to the phenolic block I made. If the phenolic doesn't work, I can go back to the aluminum one.

    I also thought about making the aluminum block and cutting or adding some fins to that .

    Thanks guys.