<div class="FTQUOTE"><begin quote>Originally posted by: Hawkman300

well, this is my first ATV and i have about 30 hours and 400 miles on it and i drive it in dusty consitions. should the air filter be replaced by now? i have taken it out and looked at it and the inside of the air filter is clean but the prefilter has one spot on it that is really dirty. i know for the prefilter just rinse it with water, but i dont know when to replace the filter. any help is appreciated.



thanks for all the input guys!</end quote></div>


Hawkman, why don't you get a stock polaris pre-filter or one from Outerwears. Its like a sock that goes over the filter. They are cheap and you can shake or blow dirt out of it and your stk filter will last a long time. Remember, K &N and other aftermarket filters just filter air. They are not performance increasing items.

 

<div class="FTQUOTE"><begin quote>Originally posted by: Hawkman300

o, it sounds just like hitting the rpm limiter trying to back up, gotcha. but what is floating the valves?</end quote></div>

Floating the valves is a term they use to describe a condition caused by excessive RPM and the valve springs ability to keep the valve seated when it is supposed to. When the valve floats from excessive RPM, it gets out of sync with the piston and they usually conact each other with disasterous results. Its like dribbling a basketball really fast till you loose control and your hand slaps it on the way up.

 

i already have a prefilter on there. i will clean it the next time i can ride this week, but i need to know when to replace the stock filter. and floating the valves is like basically blowing the engine, right?

 

Stk filter should last 6 mo with the prefilter, depending on the riding conditions.
Floating the valves usually bends valves, holes piston, or can break rods (but not always)

Like Dirty Harry said in the movie "Ya feelin' lucky"?

 

As far as removing the rev limiter you will not see a difference unless your quad is extremely modded. I did alot of testing on my scrambler with clutching and tach readings. Basicly the rpm that your quad is clutched to shift out at is your top rpm. By the time you are fully shifted out you are at top speed and the drag(wind+tires) is to great to continue to accelerate. By changing your clutching you can increase your top speed slightly but it will take longer to get there and it may seem kind of slugish in the mid rpm. The whole point of the clutching system is to keep your quads rpm at the highest HP output and start shifting out at that point. This is why a dyno will help tons when you work on your clutch. If you know what RPM your quad produces the most power/HP you can tune you clutch with a tach to shift out at that point so your always in your power band.

So example:If your quad is extremely modded and produces the most HP at 8000 rpms and your rev limit is 7000 rpms you can use that extra HP by getting a new rev limiter and rebuilding your clutch to shiftout at 7800-8000 rpms. This is an extremely rare situation that you will never see unless you are doing drag races and rebuilding your quad every 2-3 races, otherwise you may toast your engine.

Basicly if you are not sure about changing your rev limiter you should not even be considering it.

my 2 cents

 

<div class="FTQUOTE"><begin quote>Originally posted by: Hawkman300

ok, now is that when it should be replaced, or when dirt has gotten into the engine and its too late? i cant work on my atv and teardown the engine to fix it and all that.</end quote></div>

no if that happens it is time to clean/ replace the filter nothing would have happend to teh engine it is just choking it acualy if you took it off it would run fine. I do not recomend that tho i have before when i had the filter drenched with oil out on the frozen lake and it choked teh engine and stalled it i drove it off the lake and back to my house slowly with teh filter off then i swapped it out. because i always have a spare cleaned k&N air filter