2000 Suzuki DS80 build

[my67xr]

In post #58 the brass emulsion tube/needle jet comes out through the top/main bore of the carby
That has hole's across it too.

The pilot jet will only have a tiny hole through the middle of it, it's about .35mm
At the bottom of the thread's where the pilot jet screw's into you'll see another hole through to the main bore of the carby, make sure that is open

And take the mixture screw and spring out too when you are blowing it all out to make sure there isn't a blockage supplying air to the pilot
Blow compressed air into each of the small port's on the air filter side of the carby, you should feel it coming out at either the main jet or pilot jet holes in the base of the carby.
Block the mixture screw hole while you do it as well

Riding it without the air box will make it run quite lean too
The rev hang is due to being a bit lean
Have you oiled the foam filter in the air box ?
Oiling it stop's any dirt getting through into the carby body, it also help's to restrict the amount of air and will make it run a bit richer helping the mixture

 

[DMKLSIMONS]

The filter has oil on it and is new. What should I do for the Rev hang. . Screw the mixture screw in or out? Why do you think the idle is changing?

 

[DMKLSIMONS]

I have completely cleared the Exhaust. Burned out all the old carbon and oil. No washer in the exhaust port either. Also the muffler has been cleared and cleaned.

 

[DMKLSIMONS]

After running in some more. (engine has about 1 hour to 1 and half on it) I checked the compression. the compression is now worse than it was when I started. it was around 88 PSI and now reads like 65 PSI. I dont understand this. I have finally gotten the bike to run somewhat or at least as good as it had before the top end rebuild. I think this is why I am having trouble tuning it to run correctly. Its like it really never hits the powerband in upper RPM range. I dont want to have to take the top end apart again. My compression gauge is new, but was very inexpensive so it could be the issue, but before and after comparison was taken with the same gauge. Its lower now.

 

[my67xr]

When you are kicking it over to test the compression are you holding it at wide open throttle ?
It will take around 6 to 8 kick's for the oil to get into the ring's/groove's

Silly question i know, but the arrow on the piston crown is that facing the exhaust port ?
Were the original and new piston's both the same height crown to pin ?
Sometime's replacement piston's can be slightly different height's, if it is then you might need the head modified to get the correct squish?

 

[DMKLSIMONS]

Yes I'm holding the throttle wide open and kicking seven to eight times at least I made sure the arrow is pointing towards the exhaust side I don't know about the crown the pin height but the piston I took out looked completely stock. I check the compression right after installing the Rings and it was about the same 88 pS I now it shows 65 psi After run in about 90 minutes

 

[DMKLSIMONS]

I was able to get around 115 PSI average with three different gauges. Three gauges all gave three different readings. Low reading was 105, High reading was 120. This was a wet test. I opened the cylinder head as well and just checked out what was going on inside. Cylinder walls still looked good from the recent overbore and honing. Piston seems good. Could not see any issues. I did put high temp sealing gasket on with the new gasket this time to ensure no leaks. I did notice that the manual calls out for only 8.5 pounds on the torque for the cylinder head bolts. Is that correct? Seems to low to me.