|
By: Chris Hodkinson
 Flatslides,
Roundslides, TMX, PJ, PWK, Air Styker, TaperBore,
SmoothBore,etc.... the list goes on and on. Those are
just some of the choices for the modern carburetors on
today's ATV’s. For years the 2 most popular brands
have been Keihin and Mikuni but now there is a 3rd brand
called Lectron that is really starting to catch on in
today's market.
Lectron has actually been
around since 1979 but since the factories don't use them
they are a relative unknown.
1999 GNC Pro Champ Doug Gust, 1998-99 Womens Champ
Angela Moore, and 2000 Womens Champ Leslie Wells have
all used Lectrons on their quads to help propel them to
their championships. Tom Carlson of TC Racing has been
using these carbs for years now on both 2 and 4 stroke
motors. Tom has even went as far as mounting dual
Lectron Carbs on Travis Spaders 250R a couple of years
ago. Lectrons are not only found in the MX and TT races
across the Country. They are also found on the top Drag
bikes in the NHRA.
To see how the Lectrons worked we contacted Racer
Edge about them. After telling them the mods to our
TRX250R and that we want an emphasis on top end power,
they recommended the new 38x40 High Velocity Carb with a
Power Jet. 38x40---what is this we asked as most carbs
that we have dealt with only have 1 number like 36mm or
38mm, but this one has 2. We was told that the "H.V."
carbs as they call them are taper bores and have 2
different I.D. sizes. In this case the 40 means that it
is 40mm from the Air Filter side of the carb
to just past the slide then it is tapered down
to 38mm. By doing this the air/gas mixture that is being
pulled into the motor picks up speed as it is sucked
from the 40mm section to the 38mm section through the
Reeds, into the Case, and out the transfers into the
cylinder. By increasing the velocity in which the fuel
mixture moves you accomplish 2 things. 1) Is that you
get better fuel atomization with the faster movement and
2) you can pack more fuel into the case every time the
piston goes up. More Air/Fuel = More Power. Also by
doing this you have the same Top End power of a Big Carb
without the drastic loss of the Throttle response that
you normally get with a Big Carb.
Installation
Installation of the Lectron is
basically the same as any other big carb on the 250R.
You loosen the 2 clamps holding each end of the carb on
and remove the old carb and install the new one. Unless
your Intake Manifold and Airbox Boot are new you may
have to work a little bit to get the rubber to stretch
enough to get the bigger carb on. Here are a couple of
tricks that we have found to work well. The intake
manifold can be put in boiling water for a couple of
minutes to soften up the rubber so that it stretches and
slides over the carb easier. For the airbox boot you can
take your wifes or mothers hair dryer to heat it up
while it is on the machine to help stretch it to fit
over the carb.
 Once
everything is clamped on and the throttle cable adjusted
you are ready to go. Before we fired up the quad for the
safety of our motor we richened up the Powerjet (Mikuni
Pilot jet) to the max size that they sent us.
The Lectrons are quite unique
to jet. You must first understand that Lectron uses
a single threaded metering rod that is tapered.
This rod takes the place of a air screw,
pilot jet, needle, and main jet found in a Keihin or
Mikuni. This one metering rod is equivalent to about 10
main jets. For idle and low speed tuning you turn the
rod in to richen the mix or out to lean the mix.
 For
Midrange tuning you read the 2nd number on the rod. If
you want to richen the midrange up you put in a rod with
a bigger 2nd number or if you want to lean it out you
put in a rod with a smaller number. (ex. #5-2 rod is to
rich in the midrange you would replace it with a #5-1
rod).
For top
end
tuning you use the 1st number on the rod and the
Powerjet. If you find that your top end is to rich you
can drop down the number on the Powerjet. If this does
not solve the problem you will have to change the rod to
the next number smaller. (ex. #5-2 rod is to rich on top
you would replace it with a #4-2 rod and readjust your
powerjet). One small note on the rod also is that the
flat side of the rod must always face in towards the
engine. Jetting the Lectron for the first
time can be a little troublesome as it is so different
then any carb out on the market today. But once you get
used to doing it you will never want to jet any other
carb again.
Riding
 We warmed
up the quad and made some jetting runs. After checking
the spark plug and verifying our readings with our Digatron
ETG/Tach we found we were on the rich side. We put
the jetting back in that Racers Edge had sent with the
carb and now it is spot on. Better safe then sorry. The
time that it took to richen up the jetting is well worth
it if you happen to burn down the motor by not doing it.
Now for the fun part. First we went out and did some
casual play riding to get a feel for the carb. We were
surprised to see how crisp the throttle response was for
a big carb. This quad felt as if it had just as good if
not better throttle response down low then the 35 PWK
Air Stryker that we tried on the quad earlier in the day
for a comparison. Seat of the pants testing can be
deceiving though so we put it up against our test
Banshee to see if what we felt showed up on the drag
strip. After doing countless 2nd and 3rd gear roll-ons
we found that the 38x40 H.V. Lectron would shoot out
quicker and farther then the 35 Air Stryker with a great
increase in top end also.
After doing some more high
speed runs and collecting Tach Readings as well as race
results from running against our Banshee we put back on
our 39 PWK that we had on the quad before our Lectron
arrived. This is a lot
of wrenching in one day but to provide accurate results
due to the changing weather from day to day it had to be
done.
With the 39 PWK in place we
went back out to the drag strip. Doing the same 2nd and
3rd gear roll-ons the throttle response with the 39 PWK
just wasn't as good as the Lectron. The race results and
tach readings proved that the top speed was about the
same between the two carbs but the Lectron carb got up
to top speed a lot
quicker.
We have taken our Lectron carbed 250R out several
times now in various temps and altitudes and the
Lectrons do not appear to be affected by the changes in
weather as much as the Mikunis and Keihins. For safety
purposes we always check our jetting and so far it has
stayed just about spot on for our different riding areas
where as before we would have to
rejet every once and a while. Other features of the
Lectron carb are a LUSTROUS NICKEL GUILLOTINE SLIDE -
"Slices" the Air Flow for a Positive Shut
Down. Extremely hard surface has virtually no wear.
FUEL-VU TRANSPARENT FLOAT BOWL - Allows easy view of
fuel to check level or contaminates. DUAL-FLOAT SYSTEM -
Ensures a precise level under all conditions.
GREATER FUEL ECONOMY.
We were so impressed by the
Lectron carb that since our test we have installed 2
sets on 2 modified banshees and we have been very happy
with the gains in performance over the previous carb
setups. (FTZ 35mm Flatslide Mikunis and Bored Stock
carbs) We have also talked to Racers Edge about the high
cost of putting big carbs on the Banshees because you
have to replace the intake manifolds to accept the
bigger carbs. They informed us with the Lectrons you do
not have this because there is enough material that they
can turn the O.D. of the carb down to fit into the stock
intake manifolds. If you would like this done just let
them know at the time you place the order. This little
service alone can save you about $200.00.
For more information about the
Lectron Carbs you can contact them at:
Racer
Edge
1580 Forrest St
Dyersburg, TN. 38024
Phone: 1-888-558-7822
|
