1981 gs 450e (startout $50)

[surviverguy]

You won't need a fuse to do compression testing. You will need a fuse to get it to run. You can use glass fuses or the square plastic fuses. Buy a new fuse holder and fuses. Fuses for cars work fine. The square plastic fuses will be more reliable over time than the glass because the fuse holder has less moving parts.

[lorello]

alright thanks what size battery would i need i just looked at a auto store and they had a bunch a diffrent size batterys for motorcycles

[lorello]

nevermind i found the specs i was lookin for its a 12v 11 amp hours and 160cca if this sounds right the website said its an oem for my model year. hopfully i can do a compression test today

[surviverguy]

How many miles does the odometer show? You will want to adjust the valves also.

[lorello]

not sure theres no odomoter or speedometer

[surviverguy]

Look for a new valve cover gasket. You're gonna want to adjust the valves.

[lorello]

anyoe have or know where i can find a picture of the stock muffler mainly the end that goes into the motor. instead of being two seprate ones that go on both sides the one that came with my bike is a two into one and goes on the right side of the bike.. wher it flars out a little on the end where it goes into the motor mine seemes to be too long its about 1.5-2 inches off the top of my head not sure exactly but when i put it on the diamond shaped peice of metal where you screw into is about a half inch away from the muffler hopfully if its not right i can just cut a little off n itll fit

[lorello]

i rented a compression tester from auto zone and am going to test the compression in an hour or so.. but i read in a few places and on the back of the box that the testers in that it says to have the throtle wide open when you test it i dnt have any carbs or air box on my bike so how would open the throtle? wold i haveto do it or will the test still work fine

[pete]

Not 100% sure but I think the throttle wide open is to allow air to get sucked into the chamber to be compressed, whereas the throttle being closed will stop that happening.

In theory that would mean no carbs is fine... hopefully someone chips in who knows a little more than I though...

[lorello]

yea thats what i was figureing... i just did the test and it sounded like it wanted to start the back tire would spin a litlte... i barly got any compression the the needle would fluxuate but not go over 30psi..anyone kno what would cause this.. im thinkin maybe its the gauge cuse the needle should staty at the highest point right cuse min would just go back to zero on its own

[pete]

Is it sealing correctly in the spark plug hole? Is the pressure release button working ok on the gauge? If that's stuck in then the gauge won't maintain the pressure reading. Definitely sounds like a gauge issue to me...

[MisterCinders]

Your cam timing could be off, opening the valves too early and botching the compression.

[surviverguy]

Not 100% sure but I think the throttle wide open is to allow air to get sucked into the chamber to be compressed, whereas the throttle being closed will stop that happening.

In theory that would mean no carbs is fine... hopefully someone chips in who knows a little more than I though...

No carbs are needed for compression test. "throttle" will be wide open with no carbs...

[surviverguy]

yea thats what i was figureing... i just did the test and it sounded like it wanted to start the back tire would spin a litlte... i barly got any compression the the needle would fluxuate but not go over 30psi..anyone kno what would cause this.. im thinkin maybe its the gauge cuse the needle should staty at the highest point right cuse min would just go back to zero on its own

You've got two problems. The bike needs to be in neutral. With the bike on the centerstand the rear wheel should spin freely by hand. If using a side stand the bike should be able to be rolled around (when not on the side stand of course).
The compression gauge shouldn't return to zero. That's a problem with the pressure release valve on the hose near the gauge of the compression tester. The release valve is like a tire stem valve.
Be sure all (4) of your spark plugs are out of the engine.
With the gauge attached to a cylinder, when the engine spins the needle will bounce up on the compression stroke. A proper functioning gauge will keep the needle at the max pressure.
I usualy let it hit compression 4 times and that's my reading.
The battery needs to be healthy and fully charged. Using a battery charger at the same time is a good idea.
Keep a piece of paper and pen handy. Write down the reading of each cylinder when the readings are taken. Don't rely on your memory.
I hope this helps!

[lorello]

the battery maybe its brand new after i put the acid in it i waited half an hour like it said hooked it up to my dads charger ... like five minutes later my volt meter was reading 12.88 volts i ddidnt get why it would be charged so quick but i figured if it wasnt id kno when i hooked it up to the bike.. every thing seen to be working the selinod would click and the starter would go sounded like the bike wanted to start (obviously its not gonna) and i did it a lota times so im guessing the battery was charged good