Fresh rebuild - impossible to start suzuki ts125

[willis 2000]

It's probable the cylinder was hogged out with a fixed, commonly called Sunnen, hone. A true boring bar is required to get the bore straight. That's not the reason your bike won't run. Let's see, you have compression, evidently plenty of fuel, so you need only a few more variables put out of the way. Does it have spark? I mean, with a clean, preferably new, spark plug stuck into the cap and laid on the cylinder head, kick it over. Blue sparks with a nice arcing sound? CDI or points? If you have the spark I described, you can go further down the road. If not, fix this first. Oh, yeah, you should have the top end reassembled before you go to kicking it over. Use the parts you already have, unless the cylinder base gasket is torn, it'll be alright.
Post your results here, we'll get this figured out.
Oh yeah, chamfer your own ports. Get some heavy-duty 80-grit emery paper, it comes on a roll, and sand the edges of the ports until they're slightly rounded, as in, not sharp. The chamfer is to prevent the rings from snagging. Bum 3-4 inches from a bud for now. Clean the sandpaper grit out of the cylinder, for sure. Hot, soapy water works the best.
Respond to the posts on your thread frequently.

[texasadv]

Originally Posted by willis 2000

It's probable the cylinder was hogged out with a fixed, commonly called Sunnen, hone. A true boring bar is required to get the bore straight. That's not the reason your bike won't run. Let's see, you have compression, evidently plenty of fuel, so you need only a few more variables put out of the way. Does it have spark? I mean, with a clean, preferably new, spark plug stuck into the cap and laid on the cylinder head, kick it over. Blue sparks with a nice arcing sound? CDI or points? If you have the spark I described, you can go further down the road. If not, fix this first. Oh, yeah, you should have the top end reassembled before you go to kicking it over. Use the parts you already have, unless the cylinder base gasket is torn, it'll be alright.
Post your results here, we'll get this figured out.
Oh yeah, chamfer your own ports. Get some heavy-duty 80-grit emery paper, it comes on a roll, and sand the edges of the ports until they're slightly rounded, as in, not sharp. The chamfer is to prevent the rings from snagging. Bum 3-4 inches from a bud for now. Clean the sandpaper grit out of the cylinder, for sure. Hot, soapy water works the best.
Respond to the posts on your thread frequently.

Before my last round of attempts to get this thing running I replaced the points with a new set. I have spark. I checked compression again and it's 110psi. Can anyone recommend a good shop to send my cylinder to? It needs to be somewhere that is proven to be knowledgeable in boring cylinders.

Back to the hard-start issue:
I have cleaned the carb probably 8 times now. I confirmed the float setting etc. The pilot jet is the stock size and clean/clear. So my thoughts turn to float height again only because it would only idle with the idle screw all the way in, the air screw removed, and the air filter housing door removed. It seemed to start easier (compared to not at all) with a little throttle as well. So it acted like it was running rich on the pilot. So that's why I'm wondering if the float height is affecting the fuel pressure.

Thoughts?

[vtwin]

I know next to nothing about two strokes, but when I checked the compression on both the M31 and the K11p they were over 130psi. I'm assumming then yours is running a little low? Also judging by the bore wear, seems you do not have enough oil injection going. Like another said, run a little premix.