04 KX250F STARTS FIRST KICK, I CAN EVEN START IT UP BY PUSHING KICKSTART BY HAND! VALVES ALWAYS NEED ADJUSTMENT EVERY FEW HOURS!

[jorgemmartinez6509]

SO I HAVE JUST REPLACED INTAKE AND EXHAUST VALVES ON MY KAWI. I GRINDED MY SEATS AND ALL WAS GOOD, I PUT IN NEW GASKETS , PUT MY VALVES ON SPEC, ALL WAS GOOD!! WHAT SEEMS ODD TO ME IS THAT I CAN START IT BY HAND!! ????? YES PUSHING DOWN THE KICKSTART BY HAND COLD OR HOT!!. OK SO THING IS I HAVE TO ADJUST VALVES ALMOST EVERY 4 HOURS. INTAKE VALVES ALWAYS CLOSE UP ON ME. EXHAUST SEEM TO BE GOOD EVERY TIME. THIS IS WEIRD TO ME . I HAVE ABOUT 12 HOURS ON THE BIKE .ANY IDEAS OF WHAT CAN BE CAUSING ALL THIS? 

[Shawn250]

The seats should have been cut not ground, and if you used the valves to grind the seat then you can throw away the valves.

 

Did you replace piston and rings ?

 

These motors are not difficult to kick over so i suppose if you are strong enough you could start it by hand.  

[jorgemmartinez6509]

OK. So I pretty much messed up my valves?That is why i have too adjust them often? I was there piston had just been replaced by previous owner it was a very clean piston. 

[jorgemmartinez6509]

guy screwed me over. bike broke a couple of hours later. ran down a compression test and had very low compression. With compression tester hose, I used a compressor to put air in. Air was going to the carb! So lead to the intake valves I replaced the exhaust while I was there. I dind't have to grind the exhaust they were perfect seats.

[dirtbikeking843]

OK. So I pretty much messed up my valves?That is why i have too adjust them often? I was there piston had just been replaced by previous owner it was a very clean piston.

If you ground the seats instead of cutting them,.yes you probably ruined your valves, you have to cut the seats perfectly to match the surface of the valve, so yes that is why your valves are going out so quickly

[jorgemmartinez6509]

Thanks for the tip!! I am going to cut them next time I need them replaced. I love this whole repair thing have learned a lot!! Next trip is my clutch, bike pulls on first gear even with clutch pulled in tried adjusting nothing worked. Oil is gray-ish heard it can be clutch plates.

[dirtbikeking843]

I recommend having a reputable bike/machine shop cut your seats. And yes grey oil can be clutch plates. Probably is worn out. Check your basket for notching while you're in there.

[Shawn250]

Grey oil can also be a water leak into the oil.

[notoriousE-R-I-C]

Nah just have a recut. I wouldn't say ruin. Ive lapped titanium valves and everyone says not to and that motor still runs. Valvework must be perfect. Youll be alright. Depending on the math...you could be alright for awhile.

[Shawn250]

Nah just have a recut. I wouldn't say ruin. Ive lapped titanium valves and everyone says not to and that motor still runs. Valvework must be perfect. Youll be alright. Depending on the math...you could be alright for awhile.

 

He just fitted the new valves and is adjusting every ride, that means the valves are allready ruined.  

[notoriousE-R-I-C]

Id disagree. He never said if he used the valves to grind the seats. I would go to my machinist, cut a tri cut and get another 50 hours. Especially if they're new valves. You haven't ever gotten a motor, just done a little machining. And put it back together. I've raced many motors put together at minimal means. Chances are this kid ain't sponsored or got a race mechanic.

I say spend $200 on a seat and valve face cut and you'll be good. Now i dont have the bike in front of me but ive pushed some service limits in my day.

[jorgemmartinez6509]

I used the brand new valves to grind the seats. Seemed more logical to me. I do have to adjust them every few hours. I was at the track for about 4 hours, went home next thing you know after I finish cleaning it I try to start it and nothing. Wouldn't start intake valves closed up again.

[dirtbikeking843]

I used the brand new valves to grind the seats. Seemed more logical to me. I do have to adjust them every few hours. I was at the track for about 4 hours, went home next thing you know after I finish cleaning it I try to start it and nothing. Wouldn't start intake valves closed up again.

That means you did them wrong. Whenever I have replaced valves with new ones, and recur the valve seats I get long life out of them. Just like when they were new.

[jorgemmartinez6509]

OK I will cut them next time. So just to get this straight . I can still use these valves since they don't haveuvh hours or get new ones?

[jorgemmartinez6509]

OK I will cut them next time. So just to get this straight . I can still use these valves since they don't have much hours or get new ones?

[dirtbikeking843]

Get new ones to so the match up with the new valve seat perfectly

[notoriousE-R-I-C]

A good machinist will be able to tell you with one look. Id say if theyre titanium valves You may need new ones. I however, seem to rock parts longer than most. Mostly to save money. I have a machinist hookup and wait as long as possible.

Anyways. Sean250 is right. Id get new valves, id say your seats are ok. Just get the new valves and seats cut to match.

In the future, everything has numbers. Invest in a micrometer. Like you cant shim forever. Three times is a medium.

[thmike]

You've got two things that may be the problem if dirty isn't getting past the filter. One is the valves are stretching out or two your seats are getting hammered. Either way you should get it sorted out asap! Stop riding before dropping an intake valve and really damaging something.. so you can either spend a little money and fix it now.. our wait till it breaks and really cause lots of damage

[jorgemmartinez6509]

I uploaded a video on youtube on how valve head and  valves look like. 

 

https://www.youtube.com/watch?v=gztT1CoKtIg