oops.

[scotty dog]

.002" clearance on my CR according to the wiseco box it came in. Although I wouldnt think a feeler guage would be a great way to measure clearance but thats just my opinion

[TMKIWI]

0.002" or 0.05mm is correct.
And there are better ways to measure thats for sure.

Is my information wrong?

Yep.

.007? You mean .07? A feeler gauge that is made to 7/1000ths of a mm is rather small... I've always gone by no more than .04 mm clearance.

[Stusmoke]

0.002" or 0.5mm is correct.
And there are better ways to measure thats for sure.

Is my information wrong?

Yep.

.007? You mean .07? A feeler gauge that is made to 7/1000ths of a mm is rather small... I've always gone by no more than .04 mm clearance.

Maybe maths is different in new zealand... But from where I come from, .002 inches = .05 mm. Which would mean that my information was in fact, correct. .002 inches, does not equal .5mm which is a distance easily noticed on a conventional tape measure.

[TMKIWI]

My bad. Bloody decimal points.
Fixed.

[racer142]

Now that the conversion debate has been solved it looks like I'm going to need to have the cylinder replated. My question is who do yall suggest for port work. I've always heard Eric Gore but recently heard bad things and was wondering who else was around.

[evo550]

Don't worry about port work, after a new bottom end, cylinder and top end you will notice a huge increase in performance....100 hrs on a piston, sheesh!!, where's the slap across the chops emoticon when you need one.

[racer142]

Did all this last year. Thread here
http://twostrokemotocross.com/forum/general-two-stroke-talk/the-rebuild/msg47335/#msg47335
But it has since had a year and a half of hard riding on it and I kinda got curious how long it was going to last.
I'm no newb but I've never built a mood bike before. I had am uncle that went pro in flat track and mx in the 70s and he always made the comment "shift up". He always believed if you couldn't rode it locked throttle everywhere then there was no reason to mod the bike and for the most part I agree. But since it's blown I'm going to look into upgrading. But for what is worth I'm 23 racing the b class with a 9 year old basically stock 250 and have put a couple 16 year old kids with daddy's money and $20, 000 dollar bikes to shame. But I'm kinda wanting to build the bike a little different this time.

[TotalNZ]

I'd start with the suspension, that'll make the most difference in the real world.
There are little things you can do while the cases are apart though, Matching the barrel to the crankcase is pretty easy and should make it run a little harder. Also if you haven't already done so you should measure and set your squish. Also do your best to remove all the carbon from inside the expansion chamber, 100+ hours worth of carbon will kill the performance of that pipe.
If you do get an aftermarket complete crank, take it to your local engine builder and get him to check it's true. They might be able to improve on how it comes out of the box.

[Stusmoke]

I'd start with the suspension, that'll make the most difference in the real world.
There are little things you can do while the cases are apart though, Matching the barrel to the crankcase is pretty easy and should make it run a little harder. Also if you haven't already done so you should measure and set your squish. Also do your best to remove all the carbon from inside the expansion chamber, 100+ hours worth of carbon will kill the performance of that pipe.
If you do get an aftermarket complete crank, take it to your local engine builder and get him to check it's true. They might be able to improve on how it comes out of the box.

x2 on every point, particularly the first. horsepower won't do much good if your suspension tires you out. Getting suspension revalved and resprung for your weight and abilities is where I would send my money.

[racer142]

Suspension is sprung for my weight and gold valved. Also regeared the bike with a14 tooth front sprocket to smooth the bike out. Not to be rude but I've been doing this pretty successfully for a couple years. I know the basic steps but I'm looking into a few mods. I've always ridden stock bikes and raced 4 strokes so I'm asking where and what to do that's two stroke specific that's all. Thanks

[Stusmoke]

Suspension is sprung for my weight and gold valved. Also regeared the bike with a14 tooth front sprocket to smooth the bike out. Not to be rude but I've been doing this pretty successfully for a couple years. I know the basic steps but I'm looking into a few mods. I've always ridden stock bikes and raced 4 strokes so I'm asking where and what to do that's two stroke specific that's all. Thanks

Fair enough. Assuming you're in the states which I'd guess you are, Pro circuit is a good place to start for motor work. I'm in Aus so I have no direct experience but I've heard nothing but praise from their customers. There was even one dude at my local track who sent his KX250F motor away to PC for a serious ovehaul. He was considering proposing to his bike, even though the postage for his motor back and forth just about cost as much as the valve train work he had done 

[racer142]

Like I said not trying to be rude just making a point. It bothers me when I ask a question and get an answer unrelated to what I asked lol. My gf does that lol. Anyways here is a few pictures for reference to me on the kx
 


I'm not the fastest guy around for sure but I do know how to handle a dirtbike a little lol.

[racer142]

x2 on what everyone else said. And I made the 125 assumption by teh size of the piston relative to your hands. So i'm now thinking you have mammoth hands. Rule of thumb for replacing pistons is every second ring(s) change. Piston and rings, rings, piston and rings, rings, piston and rings, rings etc.

And for the record I am slightly larger than the average mxer but not much. 6 foot tall and #200lbs or 1.8 meters and 91 kg for those on the metric system. He's is a pic of me next to my bike on a lift we had just bought

[TMKIWI]

I would ask around your local tracks for any engine builders in your area.
Eric Goor is well known but there are lots of good engine builders around.
A bare minimum would be to match the cases and set the squish.

[Stusmoke]

Like I said not trying to be rude just making a point. It bothers me when I ask a question and get an answer unrelated to what I asked lol. My gf does that lol. Anyways here is a few pictures for reference to me on the kx
 


I'm not the fastest guy around for sure but I do know how to handle a dirtbike a little lol.

Yes the bum whips make any rider envious. Let me put it this way: I would love to be able to send my motor to pro circuit. But as TMKIWI said, big companies aren't the only ones who know their way around a motor. I'd be inclined to send mine to PC because I've never heard of someone who was unhappy with the invisible rocket boosters that PC strapped on their swingarms. In addition to that, it was good enough for factory Kawasaki riders back in the day.