Small guide I had in my database to share with you.
The phenomenon of Vapor Look:
Vapor look is a phenomenon that occurs in micromotors due to overheating of the
themselves due to various reasons.
It manifests itself, more so in the summer period, and in two ways:
- visual way through the occurrence of air bubbles present in the mixture tube that goes from the tank
to the carburetor;
- acoustic mode in the sense that when the mixture reaches the carburetor, it can be heard to
"fizzles" as it is called in technical jargon and evaporates instantly due to the significant
thermal difference between the temperature of the mixture itself and the temperature present in the
carburetor at the time the mixture reaches it.
The reasons that cause said phenomenon can generally be identified among the following
Which are given in random order;
- engine with little or no ventilation due to the body lacking the relevant holes to let
fresh air to flow to the head and crankcase;
- engine too compressed;
- unsuitable spark plug;
- lean carburetion so less mixture enters than is needed;
- mixture with too much % nitromethane than the manufacturer indicates on the
engine instructions;
- No. of washers present in the underhead;
- clutch worn or not properly adjusted in such a way that the engine increases
RPM significantly without increasing in speed in such a way that it cannot
enjoy a sufficient supply of fresh air thus not ensuring its cooling;
- difficulty in advancing the model due to incorrect adjustments in the transmission (e.g.
brake linkage partially locked, or incorrect adjustment of the "trim" function
on the radio always relative to the brake - wheel bearings with limited sliding due
to dirt or wear and tear on them).
Therefore, to solve the inconvenience and without upsetting the model car, one proceeds step by step to
example;
- turning without bodywork (although this would not be advisable since in case of
overturning the model one could suffer considerable damage from it) one can already verify a
possible attenuation of the phenomenon;
- by replacing the spark plug with a suitable one following this table;
themselves due to various reasons.
It manifests itself, more so in the summer period, and in two ways:
- visual way through the occurrence of air bubbles present in the mixture tube that goes from the tank
to the carburetor;
- acoustic mode in the sense that when the mixture reaches the carburetor, it can be heard to
"fizzles" as it is called in technical jargon and evaporates instantly due to the significant
thermal difference between the temperature of the mixture itself and the temperature present in the
carburetor at the time the mixture reaches it.
The reasons that cause said phenomenon can generally be identified among the following
Which are given in random order;
- engine with little or no ventilation due to the body lacking the relevant holes to let
fresh air to flow to the head and crankcase;
- engine too compressed;
- unsuitable spark plug;
- lean carburetion so less mixture enters than is needed;
- mixture with too much % nitromethane than the manufacturer indicates on the
engine instructions;
- No. of washers present in the underhead;
- clutch worn or not properly adjusted in such a way that the engine increases
RPM significantly without increasing in speed in such a way that it cannot
enjoy a sufficient supply of fresh air thus not ensuring its cooling;
- difficulty in advancing the model due to incorrect adjustments in the transmission (e.g.
brake linkage partially locked, or incorrect adjustment of the "trim" function
on the radio always relative to the brake - wheel bearings with limited sliding due
to dirt or wear and tear on them).
Therefore, to solve the inconvenience and without upsetting the model car, one proceeds step by step to
example;
- turning without bodywork (although this would not be advisable since in case of
overturning the model one could suffer considerable damage from it) one can already verify a
possible attenuation of the phenomenon;
- by replacing the spark plug with a suitable one following this table;
- possibly lengthening the mixture tube running from the tank to the carburetor to a
maximum length of 15 cm.;
- trying to run with a mixture with a lower % nitro than the one in use when the
the problem occurred (e.g., from 16% you can change to a 10%);
- greasing the carburetion i.e., opening the maximum needle by half a turn or one turn depending on
depending on the type of engine;
- insert a filter on the pressurization tube that runs from the muffler to the tank that acts
as a heat sink as well as preventing the entry of oily residue from combustion that would
would go to foul the mixture in the tank.
maximum length of 15 cm.;
- trying to run with a mixture with a lower % nitro than the one in use when the
the problem occurred (e.g., from 16% you can change to a 10%);
- greasing the carburetion i.e., opening the maximum needle by half a turn or one turn depending on
depending on the type of engine;
- insert a filter on the pressurization tube that runs from the muffler to the tank that acts
as a heat sink as well as preventing the entry of oily residue from combustion that would
would go to foul the mixture in the tank.