Pre Purchase Inspection help - 1981 Z750e

Hey KZ riders,

I'm really keen on buying a 1981 Z750e (39k on the odometer)

I've already had a look and ridden it.
Visually, it's 30+ year old bike so from what i saw it looked ok (nothing special).
The only real concern I has was there being oil grime around the engine which I'm not sure is normal for such an old bike? From what I could see there was no oil leakage.
After riding I didnt feel or hear any issues but I've only had my full licence a little bit over a year and I was probably way too excited about the bike to really scrutinise it.
So I'd really love for someone in the area with more experience and knowledge to have a look at the bike for me to get some peace of mind before laying down some money (if at all).

The bike is in Bondi (Sydney Australia) and I am potentially hoping to have another look this weekend.

Is anyone from the area willing and free to help?

Alternatively, I have a little mechanical knowledge and not afraid to ask questions and dive deeper into an inspection. is there anything I should look out for specifically?

Thanks guys!

Went to inspect a Honda 450 for a friend years ago. I stuck my finger in the exhaust to see if there was any oil. Soot is OK but not oil.
"He yelled "He even sticks his finger in it's a**hole!" :lol: He bought the bike and sold a year later for a profit.
Steve

If the bike already runs that is good. Make sure its safe to run;

Tyres
Brakes
Suspension elements, any front fork leaks
Signals

Then look for any major leakage, seeping from the camshaft cover, Cylinder head and block, and oil pan.

Check compression of the cylinders.

Everything Sharpy66 said.

A little more detail:
Checking tires: Even if they look good, check the date code on them. If they are two old you should get new tires. That is a consideration when making a purchase offer.
Checking suspension: you look for oily grim at the boot at the front lower fork tubes.
Checking brakes: look at the condition of the master cylinder and caliper for yellowish dried crud. Check the brake lines for any cracks or bulging. Check thickness of the pads.
Check the slack on the chain and the rear sprocket for wear (pricey items). You can look at the chain adjuster marks on the rear wheel to see how much adjustment is left.
Is everything there? Mirrors, turn signals, both side covers, fenders, etc ...
There should not be any oil on the front of the engine. Not familiar with the 81 Z750E, but if it has a mechanical RPM cable gear connection on the head, it could be a simple seal replacement if the that is the source of the leak.
Look for any frame damage. Inspect as much as possible the frame for any malformations and cracks. With the bike on the center stand, look at the back wheel alignment with your eye level at the level of the rear wheel looking toward the front of the bike.
Check all electrical. I always check the horn. It is a critical safety component. Low/high beams, signals , rear tail light (running light / brake light) , license plate light. and instrument panel lights (sucks not having instrument lights when riding at night).
Check the oil level. Doesn't hurt. If it is low, it could be due to the leak and tells you how low of oil the bike allowed to operate on.
If you can get a compression test as Sharp66 suggested, that would be very valuable information. But the engine has to have been brought up to operating temperature in order to get a proper reading.

Al these things considered together will give you a good sense of the condition of the bike and how much to offer the seller for it.

Very good advice from KZJOE900.

Yes check the oil level I would even go as far as suggesting to do an oil change and oil filter change.

My project bike had no oil filter when I pulled the oil pan.

Ironically, really dirty grime in some areas indicates a possible slow leak of oil, but is not a big deal.
Really clean looking oil on the motor indicates a bigger leak and possible issue to worry about.