Old motor acting up

R

Rudz

New Member
I bought my old bike out and it wouldn't start.

I cleaned the carb and replaced the magneto.

This is a new top end that I installed before putting it away. The clutch pads are also new.

I have a new NGK spark plug and tested two different cdi's.

When I pedal it and drop the clutch the motor turns over and tries to start. The cylinder even warms up but no start.

I tested the compression by putting the bike up on its kickstand and stomping the pedal and I only got 25 psi

Should I pedal it up to speed then drop the clutch for a more accurate reading?

When the clutch is engaged I can move the rear wheel by hand.

The flower nut is set where it engages the clutch just right. Any tighter and it wont disengage and any looser and it doesn't enage at all.
 
check clutch cable for stretching - pedal to get an accurate compression reading - don't forget fresh gas
 
I reset clutch cable already. I tightened the head nuts tighter than they should be and stomp compression went up to 60. I have those stupid acorn nuts. I dunno why, I must have left my good nuts in California.

There's a possible culprit I didnt think about. ..
 
You can easily snip the heads off the acorn nuts or you can just crush the heads with pliers and wiggle a bit. They are quite thin and come off easily.
 
Not all acorn nuts will pop off -some are really thick metal at the top but
WARNING I tried to grind the closed tops to open nuts holding with a vice grip and the heat took the temper from the nuts so they were garbage.
WARNING there are two maybe three sizes of head bolt threads so make sure you have the right pitch 8mm nuts when you mess with the head off and replace the nuts!!!
 
Hey Rudz,

You said "new top end before I put it away". did it run before you put it away?


1. Make sure you have good fuel flow out of fuel petcock and line ( new fuel? )

2. Check intake gasket to cylinder and carb to intake seal for air leaks

3. Visually inspect base gasket at bottom of cylinder (Did you remember to put it on? not being a jerk but everyone makes mistakes)

4. Remove Mag side cover and inspect for leaking fuel or blackstuff seeping through seal behind magnet.

5. Do the same on clutch side behind drive gear

I hope it is something real simple for you and a lot of times it is, Good Luck and have fun
 
It was the stupid nuts.

Swapped em out. Torqued it down and she fired right up with gas from early summer lol.

Now I have to break in the new top end. It struggles uphill but I'm hoping that'll go away with break in and maybe new fresh gas.
 
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