shifting shaft that goes to trans cast aluminum or cast iron IS 90 psi compression ok for 74 xlh 1000cc ironhead sporty thanks for the manual # have to learn to read it but can't find compression

 

I am not trying to sound like a jerk but i really have no idea what you are asking.

 

H-mmm, I am going to try to decipher what you are asking here.

The shifter shaft is neither cast iron nor aluminum. It is made of steel.
90 psi is on the low side but should be OK. More importantly, what is the other cylinder?
Both cylinders compression being about the same (give or take 10 psi) indicates equal wear and is a good thing.
A cylinder that reads much lower than the other one indicates problems in the low cylinder. This is of course a bad thing.
A low reading could be worn valves, worn rings and damaged piston, or a combination of all those things.

When you do a compression check you should turn the engine over 3 or 4 times while holding the throttle wide open.
This allows the engine to intake a full charge of air and gives a more accurate reading.
pg

 

shifting shaft part what kind of metal is it made out of

 

both were 90 i forgot to add that i think the book is saying 120psi hard to read and understand

 

Yes, 120 is about normal for a new engine.
Yours being both 90 psi means normal wear has taken place in both cylinders. So be assured everything is as it should be.

When the rings get really worn you will see some oil smoke coming out of the tail pipes. That is what I always look for and a bike can run a really long time burning some oil. Not to worry.
pg

 

Steel, in case you did not see my earlier answer.
pg

 

read broken heart & u will understand can the steel shifting shaft steel part be welded

 

If the shifting shaft is broken it can be welded, but to do so requires the entire clutch and transmission be removed.
A better option, if that has to be done, is to buy a new shaft and install it rather than trying to weld up a broken shaft.

The shifter shaft I am referring to is #17..............



If you are talking about breaking the shift lever, then it too can be welded and is a simple fix because it is an external part, easily removed and easily welded.
pg

 

For the compression test the engine should be warmed up and the throttle fully open. Cold engine or closed throttle will give a low reading.

Cylinder Compression And Leakage Tests

A compression test should be done as part of each tuneup. Record the results and follow any changes over time.

A cylinder leakage test should be done any time you are considering taking down the top end. This test gives you useful information regarding what you should look for when you have it apart.

Each of these requires a tester which you can buy at an auto parts store. A compression tester could be found for about $40.00 more or less, and a clyinder leakage tester for somewhat more than that amount. With the cylinder leakage tester you will also need a small air compressor. Should be able to find a small sausage style for under $100.00.

Use these tools once and they have paid for themselves, compared to paying $50.00 to $100.00 per hour at a shop. Buy a slightly larger air compressor [look for about 5 CFM @ 90 PSI] and you will be able to use it with air tools.


Compression Test

1. Ride the bike to get the engine to get it up to operating temperature
2. Disconnect and remove both spark plugs; insert them into the leads and place them on the cylinder heads for grounding
3. Screw the compression tester into the spark plug hole for either of the cylinders
4. Hold the throttle open, and ensure the choke plate is also open [choke **** pushed in]
5. Crank the engine through several rotations until there is no further increase in reading at the tester gauge
6. Record the final reading
7. Repeat for the other cylinder

The difference between the two readings should not be more than 10 psi. A low reading on one cylinder indicates possible valve or ring damage to that cylinder. To determine which, pour about 1/2 oz of oil into that cylinder through the spark plug hole and repeat the test. If the reading returns to normal then valves are good, rings may be defective. If compression does not return to normal then valves may require service.


Cylinder Leakage Test

This test will tell you what to look for at the top end tear down: worn exhaust valves, worn intake valves, leaky head gaskets, or worn rings.

This test is usually done immediately following a compression test. So the engine is at or close to normal operating temperature, and the spark plugs have been removed.

1. Remove the pushrods to ensure that the valves are closed.

2. Set the cylinder to be tested at or near top dead center [TDC] as this is the wear area for the rings ...

a] rear wheel off the ground, shift to 2nd gear, rotate wheel until it clicks, repeat until you get to 4th gear. Now by rotating the rear wheel you are rotating the engine. Almost impossible with the plugs in; very difficult in lower gears. For the following it helps to have either a shop assistant or a wide "wingspan".

b] you can see in thru the spark plug hole, especially with a flash light. You can also try inserting something soft like a pencil and watch it rise and fall as you rotate the engine with the back wheel; but be careful it does not break or get stuck! You will have to hang on to the pencil with left hand while rotating the rear wheel with the right.

3. Turn on the compressor, connect the gauge to the air pressure, and adjust the gauge
4. Thread the adapter into the spark plug hole and attach to the gauge
5. The gauge now shows the amount of leakage
6. Listen at each exhaust pipe. Excessive hissing here indicates the respective exhaust valve is not sealing
7. Listen at the A/C intake. Excessive hissing here indicates intake valve[s] not sealing
8. Listen at the timing plug hole. Excessive hissing here indicates the rings are not sealing
9. Listen around the cylinder/head connection. Excessive hissing here indicates the respective head gasket is not sealing


Notes

A mechanics stethoscope [with the probe removed for this test] makes a good listening device, as does a length of oil line hose.

Greater leakage results in a sound of lower pitch.

There will always be some leakage, especially past the rings.