©2005 olilolo productions
all rights reserved. orsome crap, anyway
|Ok, this was originally anattempt to make a RAM induction system for the 250 however I ran intodesign flaws that has set back the RAM a while but gave me a veryeffective and workable Cold Air Intake system. |
The standard intake method of the CBR leaves alot to be desired. First of all, The "Direct Air Intake" that comes onthe bike is a complete farce. Those ducts on either side of the bike dono more than guide air to the sides of Carb #1 and #4 and the ductedair has nowhere to so but down and away from the airbox. Theairbox is situated under the tank and has a little pig snout attachedto it that forces the carburetors to draw air that sits stagnantlyabove the hot engine. The hotter the air, the less you can fit into thecombustion chamber because it's expanded. The colder it is the more youcan fit in there, because cold air is dense. Therefore, if you candirect cold air towards the carburetors, the better the combustioncyclewill be.
My prototype consists of the following.
2 lengths of 50cm x 4.5cm corrugated hose
2 x small plastic bottles
Usually, the best place to have your intake is at the furthermostforward pointof your vehicle, in this instance the two air vents either side of thetop fairing are the best options. First I removed all the air guides asthey are useless as tits on a bull in my opinion. Next, I cut the twosmall plastic bottles to fit wide end first into the air vents. Bottleswith a tapered top work best. One thing to make sure of is that yourhose will fit onto the top of the bottle also. Now comes the hard part,this may discourage some people. You need to cut a slot into yourairbox upper. All I did was cut the snout off, widen the hole and runthe hoses under the tank. Having the hoses running here meant Ihad to raise the tank and perform some minor panel beating of the tank.I connected the hoses to the top fairing and that completed the Intake.
As for the air-filter, there isno need to shell out $50 to $100 fora K&N or Unifilter "race" filter as you can make one out of yourold [andprobably very overdue for replacement] genuine filter. The genuinefilter is a crappy cardboard airfilter and would be an ideal filter fora vehicle traveling along dusty roads, however as I rarely take the2-fiddy cross country I went to a rubber outlet [Clarke Rubber, etc...]and asked for some "Automotive Polyurethane" as that is what most racefilters are made from. I removed the cardboard fins from the filterthen cut some foam to fit. This material does need to be oiled though.2-stroke oil is what they use to oil them, don't go buy "air-filteroil" as it's just over priced 2-stroke oil. Make sure you remove anyexcess oil. I cannot stress this enough. I did some research on thecorrect oiling techniques from K&N and they said "Saturate thefilter but don't wring it out. Dab the excess away with a rag."
DO NOT FOLLOW THATADVICE IF MAKING YOUR OWN FILTER!!!
Just leave the filter dry. I had previously advised to oil them but
all this does is eventually make a mess of your airbox and actually
makes your carburettors dirty as they are constantly consuming oil.
Even if you use proper K&N filter oil it still makes a mess.