How often for valves on a kxf?

My friend who is in the series for B class 250 and 125 c with his 2010 kxf told me that he has only had to spec his valves once with two years of heavy racing on the bike. He just says that he cleans his filter religously to keep the engine clean and thats all he does. He says the only engine maintence he does is upgrades. Feedback please. I have been cleaning my filter every 10 hours and was just wondering.

That seems to be pretty normal for KX250F's. The general rule of thumb is after one goes out of spec once and you adjust it, if it moves within 5 hours of riding, it's time to replace the valves (along with new springs and getting the seats cut).

Wow, I totally missed that last little bit.

You're asking for problems if you only clean your air filter every 10 hours.

Clean your air filter after every ride as mentioned below.

Edited by chasemotox63

Clean your air filter EVERY 10 HOURS?!?!!?!? You should clean that thing after EVERY ride. The only time I've ever not done it every ride is if I ride my 125 most of the day and only spin a few laps on my 250f i'll use it again but anything more and she gets cleaned. My filter is soiled after 2 hours at the track.

every 10 hours is after a ride lmfao when i go riding usually i go out at 7 and am done around 4 or 5, unless its after school riding which is just for a 20 minute spin but i ride every weekend all day

and with where i ride my filter somehow manages to stay pretty clean, i have a twin air filter btw

Every ride is overkill. You can ride until the filter looks pretty friggin dirty and is beginning to look like it may be blocking airflow. A filter with dirt on the outside actually filters more than a clean filter. i.e. less dirt can get through.

Unless it is super dusty, a filter can go quite a few rides between cleanings. I'm not really sure where the obsession for cleaning them comes from. You actually probably dislodge more dirt by cleaning it than running it a little dirty.

Valves on the other hand should be checked often. For recreational riding, maybe every twenty hours. until they stabilize. Then whenever you notice it's hard to start. My bike is a one kicker when the valves are in the middle of spec.

my bike will start first kick hot or cold choke or no choke so im sure the valves are fine its just for future reference

i just do my filter when it gets dirty, I dont really have a set time I do it. and for the OP who says he does 10 hours a day, get an hour meter, you probably ride 3 hours at most!

I check valves every 10 hours, piston at 60

and for the OP who says he does 10 hours a day, get an hour meter, you probably ride 3 hours at most!

+1! and i say 2 hours at the most.

i usually do ride that much im not someone who goes out and sits around or goes to a track and rides for 30 minutes i go to practice tracks and pits and ride hard for hours and go through ALOT of gas when i can only ride for 3 hours i usually say its not worth it and dont go riding

Im saying it feels like you ride alot, but once you get an hour meter you will truly be surprised. I ride 2 times a week all day putting in hard laps at the track and I have put 30 hours on my bike since Jan.

I've never seen anyone ride 3 hours at the track. That would be pretty crushing. More than that would be ironman territory.

.....but anyway back to the original question, with proper maintenance, all of my KX250F's go 90 hours on a top end and then I replace the entire valve train along with piston/rings. Even after 90 hours of practice and racing this is only done as a preventive measure, as I have never had an engine failure of any kind.

More important than how often you clean your air filter is how careful you are doing it. There is a technique to keeping ALL DIRT out of your intake tract. Learn it or pay the price.

More important than how often you clean your air filter is how careful you are doing it. There is a technique to keeping ALL DIRT out of your intake tract. Learn it or pay the price.

Care to iterate on the proper technique?

idk i check the time when im riding and dont take a brake for more then 10 minutes and ill take mayb 5 brakes in a day if its real hot and im there around 7:30 and leaving at 5

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