please HELP,at witts end!

ok everyone. my 550 maxim motor runs fine, but 2 headers do not get hot. so....i checked compression, its 70ish on all four cylinders erywhere .i also have spark and i have new plugs, and i pulled all the plugs after a few start ups and runs. from left to right, left being number 1. number one plug looks like new, but loaded with fuel. number two plug is a little brown, but still looks new. number three is kind of dark, and so if four. well the headers that stay cold are number one and two. so i took the bowls off, and cleaned the two jets in each carb. i alsocleaned the little whole in the bottom of the bowl. also the thing under the float with the screen on the bottom were clean on all four carbs. here is where my question is..... the "needle" seat...it looks like a jet with a spring on it, and its very skinny. it was clean. and i turned it almost three turns down, and then pulled it out. cleaned it and decided to back it off three whole turns on all four carbs. but if i am right dosnt the "needle" seat thingy, regulate fuel supplied to the carbs or motor. if it does, opening it more turns must allow more fuel and screwing it down must decrease the fuel supplied. do i need to tighten the "needle" seat screw down on the carbs where the plugs are clean with no burnt? and put more open turns on the carbs where the plugs are really dark in order to wind up with a good mixture? are all the carbs supposed to be set the same, or do i adjust them as needed using the plugs to determine the mix? please let me know. thanks guys.

 

You need to check compression with the throttle wide open. If it had only 70 pounds of compression it wouldnt run

 

heres the scoop, yeaterday, my friend held the throttle open while i cranked the bike over, and helt the comp tester. it read 100. then he left, and i did not open throttle....thats when it read 70. so i get your jist. i went to check it tonight with a friend, and the batt was dead. ill try tommorow with throttle open. for giggles, lets say i have good compression, which i think i do, and will find out soon, what should i do?

 

I had a similar problem with my 3 and 4 Cylinders. 3 and 4 arent controlled by the same coils so that narrowed my options down.
I actually had the air jets underneath the piston diaphram mixed up when i cleaned the carbs. Made a huge differance.
The mixture screws next to the choke plugers on the carbs only really controll whats happining in your bike below 2K RPMS. Idle speed. If you're letting her sit and idle for like three min you'll get that reading on your plugs. If they're dark, turn clockwise to close off gas injection. Trying to get a good tan color. If the plugs are white, then open the screws up, (counterclockwise) and then test. Put fans on the engine if you're gonna test a lot.
To get a reading at what your bike is actually doing when you're in traffic you need to do a plug chop. Ride your bike up at like 4-5k rpms and hit the kill switch. Coast to a stop, check your plugs. If they're white, new jets in the carbs. Dark, well. dark is ok.
-SLKid

 

To properly check your cylinder compression:


Battery FULLY charged.

Engine at operating TEMPERATURE.

Spark plugs OUT (on all cylinders).

Spark plug wires GROUNDED to the head (or you'll burn up your TCI unit!).

Throttle WIDE OPEN.

Crank for about 5-10 seconds on each cylinder, or until gauge needle stops "popping" to higher readings.

RE-CHARGE battery between different cylinder checks if it is getting weak after cranking for 10 seconds.


Report back after that is done. Until the issue in regards to the compression is determined AND RESOLVED, everything else is merely conjecture, and far too many "what if" scenarios to list.


However, assuming the compression is okay....and by the way, 100psi is still TOO LOW (assuming all of the above requirements are met).....then the first step is to check valve clearances, and remedy any that are out of spec. Because any other attempts to adjust carbs when the valves are out of spec is, again, just a waste of time! (I know you're tired of hearing that by now, but it's the truth, and following the proper procedures will actually save you time, money, and effort).


Once the valve clearance are all in spec, then the next step is to make sure all the carbs are completely, thoroughly clean internally. Will probably require a complete rebuild, because unless YOU have already rebuilt them yourself, they probably haven't ever been rebuilt (or rebuilt properly), and they are, after all, closing in on being 30 years old.

Once that's done, then you can synch and fine-tune the carbs via the mixture screws and getting it purring and performing like new.


Skip ANY of the steps above, and I'm afraid that I can't be of much help to you on any advice (and neither can anyone else, regardless of what they say; they're just guessing!).

You're trying to go about "fixing" the engine in the exact opposite order in which it needs to be done......and that will lead to more frustration and lost riding time and expense that you can possibly imagine! :cry:

 

And get a screw in compression tester not one of those rubber tipped pos

 

If you can't ground all of your plugs, disconnect the TCI plugs (6 pin is more important than the 4 pin but that is splitting hairs). This will keep the TCI from cooking itself.