Be carefull checking valves

Just a warning to be very carefull with the valve cover seal. A customer with a kx250f 09 shimed the valves and when re-fitting the valve cover tightened it down with about 1" of the seal at the front of the motor popped out. Went for a ride in wet muddy conditions and after two hours the motor stopped.

Pulled the motor apart today and found it to be full of grit. It has worn his cams and journals to the point of siezing the motor. Scored his cylinder pretty badly too and worn his crank bearings. Looking at least 2k just for parts. He is real bummed as you can imagine.

Wow....that does suck........bummer.....

Damn, I feel so bad for that guy.

i pinched the gasket at the misted out oil and eventually flamed up during a race.

I did that once too. On a brand new big bore fully worked engine. Fortunately I realized it in the first thirty seconds and no damage resulted. Just a big mess.

Check twice, tighten once.

and we need to watch the 2 orings around the spark plug hole. that sucks! always take your time rebuilding and double check your work we all make mistakes.

With a new complete motor assembly costing $3100 there in the US it might be better to chuck the old motor. Contaminated oil has been through the transmission and clutch and we haven't even looked in there yet.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Similar Content

    • By DirtBikeHead
      2015 Kawasaki KX250f - 20 hours
      As close to new as I'd imagine you'd get! I bought the bike brand new, I'm older and have taken extremely good care of this bike. Very little use and is COMPLETELY stock - everything is original. 
      Comes with the title, original book and map couplers for the fuel injection.
      $4700 - cash 
    • By CodyR
      Just thought maybe everyone could post up there youtube channels an we could all help eachother out by subscribing to one another.
      Heres mine ill sub back asap.
      This has been fun in other sections of TT, so I'll start the thread here and see if we can keep it going.
      Let us know what kind of mods, fixes, changes, etc.., you performed today, or just general fun you had with, your KX250F.
      I'll start with.. I installed a correct for my weight Race Tech shock spring, along with a Pivot Works shock spring thrust bearing. Also cleaned out all the nasty yellow plastic/wax crap that passes for grease in the lower shock bearing, and re-lubed it with Bel Ray waterproof.
    • By bangmyhead
      Time for a top end on my bike, just wondering if there are any alternative Valve springs i can use. I have PC cams and $400 for just the springs and retainers is alil costly at the moment.
    • By MotocrossMaverick
      Hey guys i have just gotten off my Honda crf150r and i am looking for a new bike. I have been to the dealership and have already checked out the Kx250f and the Crf250r. I am looking more at the Rm-z250 then any other bike right now. I need help finding what bike would be best for me. I have never been on a 250 but i am starting racing about a month after getting the bike. I was also offered $5800 for the Kx250f and i know it killed 2012 i am just not sure about a Kawasaki. Honestly i am not sure bout any please help!!