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ok i took it into the trails. I rode for about 25 minutes. Enough to get the bike nice and warm. I probably went to 3/4 throttle sometimes. I went up a few steep hills to put some load on the motor. Anyway, after this it took me about 3 or 4 minutes to get the tank and seat and stuff off. When i did the test with the throttle wide open i got the same results as before. ONly 125 PSi. maybe this is the reason i am having no power?? I was kinda hoping after the top end job it would be around 145-150 psi. I put in a new plug before i left and pretty much it looked the same as the first. It wasnt wet put was getting black. Seemed almost like carbon build up. Also it is taking me more kicks to start the bike than it use to. Before it was like 1 or 2. Now it is like 2 or 3 or 4. I didnt mess with the air screw as my main goal was to get the compression. If anything the plug would indicate a rich condition so that means i would need to close the air screw a bit maybe??? thanks. It is at like 1 5/8 turns should i maybe go to 1 3/8 turn??

You need to go the other way with the mixture screw to lean it out, counter clock wise.

"ONly 125 PSi. maybe this is the reason i am having no power?? I was kinda hoping after the top end job it would be around 145-150 psi"

Ryan, I take it you are repeatedly kicking to get the most acurate/highest compression reading, along with the THROTTLE WIDE OPEN, RIGHT
And the bike is up to operating temps, RIGHT
If so, SOMETHING AIN'T RIGHT IN NEW YORK
You may have to re-inspect the nut & bolts of things. gaskets would not hurt either.

i was thinking maybe since the cylinder has never been touched that is the problem. I would say i have done everything on your list. Im guessing thats just the way the bike is gonna be. I turned the air screw out about 1/8 of a turn to make it a bit leaner. Seems to be running decent. Since i was about 2 1/2 hours into break in i rode the bike like normal. Seems to be doing pretty good. I am thinking the lack in power is maybe the chain. My adjusters are on 8 so maybe it is time for a new one along with sprockets.

"I was thinking maybe since the cylinder has never been touched that is the problem"

Ryan I thought you did the Top-End??!!
You did not Cross Hatch the Cylinder Walls???!!!
The rings MAY NOT be seating properly or they slipped out of position when installing back into the jug

i cleaned the cylinder to get all the old oil and grease out. I used a a sponge to clean it and then i dried it well.

As far as cross hatching i dont know that term. I probably know what it is just not by that term.

You should of used a Scotch-brite pad to rough up the surface and break the glaze. This is probably your problem.

Ok well 125 is ok right?? Or should i not be riding it with that compression? If i bought new rings and then roughed up the surface of the cylinder would they seat better??

Basically i am going riding this coming weekend with my cousin and his new kdx but if i shouldnt ride my bike in the current condition please let me know!!! thanks

New rings? I would.

Ride it as is? That's fine. 95-151 is acceptable.... your in the middle.

Ryan, I don't understand. All this talk about how to break in. What the hell were you trying to break in?????

the new top end i bought and installed.

alright well since i can change the rings in less than a day i think i will do it after i come back from riding with my cousin. So basically if i score the cylinder lightly with a scotchbrite pad it will help the rings seat better right?

Yes.... It will give them something to grab onto so that they may wear into the cylinder and seat.

Likely we should give you a bit more information about scoring your cylinder with Scotch Bright pads. Number of articles out there on the net although none popped up a minute ago and I only got a couple of minutes to waste.

Green pads work for me for a cylinder in good condition without much glaze. The highly polished cylinder 'Glaze' should be removed and cross hatch pattern should be evident; unless of course the cross hatch is worn away which is not so good.

Clean the cylinder very well after scotch padding. I use solvent followed with white paper towels until the towel are clean.

FWIW - the old Yamaha manuals had you scuffing the cylinder bore with about 320 - 400 grit wet/dry sandpaper. I still find this to be very effective especially on well used cylinders. The clean up however has to be VERY< VERY GOOD. I use a light solvent (WD40) or light oil to perform the scuffing. Followed by solvent cleaning - followed by soap and water cleaning repeated then wipe with clean white towels covered with WD40 until they are as white coming out as entering the cylinder.

i just did a compression test on my cousins bike without even warming it up and it had 135 pounds so now i think i will rebuild it next week.

Is the bike going now after you took it in ryan? i seemed to have lost that point in all the posts. if it is still dead. i had a simlar problem once with mine. found that the button
washer in the kill switch was stuck on the 2 contacts!! therefor earthing CDI out. no spark!

ive got spark now, the only bad thing i have is kinda low compression. And my rear tire is getting a new tube because it was really flat but i should have it back by today at like 3.