Bought a cheap carbureted motorcycle about a month ago I've been riding it around since. Got the idea today to clean the air filter, so I open up the airbox... and there's no filter (there's a spot for one but not installed, albeit there's a screen before the carb). For all I know it's been running like this for years.
Makes me wonder how necessary one actually is?
>Makes me wonder how necessary one actually is?
depends, how much sand and dirt is there in the air on the roads?
take off the head and peek in the cylinder bores to see if any damage has been done
change your oil daily and you won't have a need for one.
Since it's a carb it does indeed need one STAT (or a rejet) because it will run lean without that extra restriction on the intake.
Dirt isn't too big a deal as I've sucked in plenty on a couple good motors and it never seemed to worry them, might change over the course of hundreds of thousands of miles however.
>it will run lean without that extra restriction on the intake.
Please stop posting and go kill yourself.
Why isn't this true?
I can just buy a foam filter for $5, but I'm a bit reluctant to (as OP) since I figure I'll need to fiddle with the carb to compensate (presumably it's been turned for no filter since it runs well).
That's how carbs work, if you take the air filter off a stock carb car it will run lean, do some research.
...in this vein, which flows easier: oiled foam or paper?
>if you take the air filter off a stock carb car it will run lean
What is tuning a carb?
>hurr durr no air filter
>I'll just leave it as is instead of fixing it
>I can't into carbs
fucking hacks.
I wouldn't run oiled foam unless it was 100% off road only. Paper otherwise.
>(or a rejet)
Do you have selective reading disorder or are you just plain stupid?
The point is that the fear of adding an air filter to a carb is retarded. Buy the air filter and tune the carb if needed.
You have a funny way of apologizing but sure I'll accept it.
Is non-oiled foam useless?
And you accuse me of a reading disorder.
I ask because when I google air filters for this shit third world bike (Suzuki GN125) most seem to be foam condoms, which I presume should be oiled.
If you're not apologizing you should be.
In fact you should really delete your first post or two.
Holy fuck some most of you are retarded. Yes the motor may run, but it's not good for it to suck in particles over time, that's why it's there. It will also lean out the mixture. Yes you can tune it , but that involves installing larger jets and most likely trial and error.
Most of the time, the only thing that is adjustable is the idle circuit, and since like 1999 they even try and stop you from doing that, with brass plugs they install over the af screws. Fucking epa.
Pictured is a stock 99-02 S650 airbox. If you slap on a K&N-type air filter without rejetting the carb it WILL run lean. Carb's cant self adjust like EFI can.
Carbs work by the venturi effect.
Air flow is air flow.
Temperature and elevation are the real variables.
Why do some classic bikes come without a filter then? My uncle has some old Benelli from the 1930s, and it doesn't have a filter on it, the intake side of the carb is just open to the elements.
>If you slap on a K&N-type air filter without rejetting the carb it WILL run lean.
even on a relatively large automotive carb?
Don't a lot of seriously classic vehicles use oil bath air filters? (not sure if that's true of bikes though)
Air flow AND vacuum - increase airflow will increase the fuel sucked through but so will increased vacuum. Reducing restrictions lowers vacuum, which lowers fuel, while simultaneously increasing air, creating a leaner AFR - this is all well documented
>how does a choke work
In one thought you're saying a restriction makes it run rich, and in the next you're saying a restriction makes it run lean.
Which is it soy boy?
nm no ur not
>you're saying a restriction makes it run lean.
[citation needed]
I don't know why you're still arguing as I've said: this is all well documented.