Car oil. Have i killed my clutch?

Well, I am glad we have that settled. :laugh:

Martinbr wrote:

Hi,

Today i put some oil (approximate ½ litre) in my oil tank on my KZ 400 from 1975.

This is the first time i have put oil on since i bought it.

Only problem is that i used a car oil. It was Shell Helix Super 10w-40.

I havent riden the bike since i put the oil on. Here tonight while browsing motorcycle sites i saw that you should never use a car oil on a motorbike with wet-clutch

My questions are now:
Have i killed my clutch?

Unquestionably. I will hold a moment of silence for it and then a brief but tasteful memorial service.:laugh:

I have run nothing but car oil in my 750 twin for 30 years, that's about 80k miles (I've run dino oil, synthetic oil, and mixes of the two). Mind you, that's 80k miles and still running the original bottom end. Some people have reported slipping clutches if using the "energy saving oils" but I have run them many times with no problem on the original clutch and the second one I put in at about 60k miles. No problems.

i tried to run some super light weight oil one time in my drag bike 0-40 castrol synthetic and i didn't experiance any slippage just the oppoisite the clutch would not release it kept trying to pull me through the beam's it was so bad i redlight 3 passes in a row i went back to my trailer after the last one and dumped the oil out and replaced it with some 20/50 quaker state that i had and the problem went away immeditly. just to be sure it was the oil i pulled my clutch apart and i have never seen drier plates in my life it was just like i had washed them in solvent. i wont ever make that mistake again.

When i got my 77 650b1 running a couple weeks ago i put in shell rotella oild 20w-50, and have been riding the piss out of it and it runs fine, no clutch slipping at all.

Thanks again for all the great replys.

I am so glad to hear that the slipping clutch probably wont be a problem. The oil leak is already a big issue for me, it leaks oil as if someone paid it to do so. But its my understanding that this is a common problem with the kz400 before 1976 (mine is a 1975).
So i guess i just have to live with the oil leak Or is there something i can do?

I have just taken a few pictures of my bike:



There is a lot of work to be done

That's a good looking bike.

Just adding to the "I've always used regular car oil and never had a problem" list. Castrol all day, all the time.

Granted, I haven't been doing it from 40 years like some guys around here, but I'll be sure to post my results when I get there. :lol:

I read something somewhere years ago that Castrol GTX was used recycled oil. Is there any truth to this? It really does not matter to me as I have used Castrol GTX 20W-50 for 30 years, from my cars and trucks, to my bikes, to my moped, to my scooter, to my lawnmower, to my generator, to my hand pump oil can in my garage. Never had an oil related problem on any of the above.

I like the look of your bike. I have not really seen one that compares to the style. Sort of like a bobber / racer hybrid.

Cool Look with the spoked rims.

YUKABODOS wrote:

I like the look of your bike. I have not really seen one that compares to the style. Sort of like a bobber / racer hybrid.

Cool Look with the spoked rims.

Thanks

Its far from finished though. I need a new slim saddle, paintjog on the tank, new rear end, removal of side panels and total rewirering etc.

Yeah I have a kerker on my bike. I roughly figured I needed an additional .5 quarts for the amount of hose and the cooler. I just had a bit of an overflow the other day during some heavy riding and drained a bit out. I just fill it to the top of the looking glass. Seems to be working ok. I guess the best bet would be to precisely measure it out at changing time, and then add the half a quart.

I have never used pure motorcycle oil in any bike I have ever had. It's a rip off. I used castrol and in 30 years of riding have never had a problem.

donthekawguy wrote:

I have never used pure motorcycle oil in any bike I have ever had. It's a rip off. I used castrol and in 30 years of riding have never had a problem.

When I bought my KZ750 new in '79, the dealers around here ONLY used castrol GTX. I used it for probably 20 years, never a problem.