[srini1785]

I have been grappling with an annoying oil leak in one of the motorcycles that i am trying to restore. Its a 78 model honda cd185 twin. The problem is simple. While on center / side stand there is no leak whatsoever, when the engine is started, it leaks close to the mid section of the center stand.

I am reluctant to remove the engine from frame as i have already done it 3 times and it weighs a ton. Fixing it back to the frame is a 2 man job and yeah absolutely no question of splitting the cases. No, not at this point.

What are your suggestions to locate the source of leak? and how to remedy it?.

[ashwinprakas]

Originally Posted by srini1785

when the engine is started, it leaks close to the mid section of the center stand.

What are your suggestions to locate the source of leak? and how to remedy it?.

Isn't that where your crank case breather is located?

If so could it be that your rings are weak which is resulting in oil being discharged when the motor is running? Or simply cause you'd overfilled oil?

If it were the shifter seal, sprocket seal/collar or the neutral switch then the motorcycle would leak when kept on its side stand:



On the CRF's and CB's of yesteryear they have a kicker stopper that sits under the crankcase, on the Unicorn etc it extends to be forward set pegs, the mounts are prone to crack and at times would result in leaks, but that is usually noticeable even when the motorcycle is left idle.

Regards,
A.P.

[srini1785]

Originally Posted by ashwinprakas

Isn't that where your crank case breather is located?

No. The breather hose entry ( don't know the exact tech term) is located on the top side of the case and the leak is on the bottom side ( am pretty sure of it).

Originally Posted by ashwinprakas

If so could it be that your rings are weak which is resulting in oil being discharged when the motor is running?

You mean piston rings?. could you please explain?.

Originally Posted by ashwinprakas

Or simply cause you'd overfilled oil?

No. Filled as per manual 1.5 Lts.

Originally Posted by ashwinprakas

If it were the shifter seal, sprocket seal/collar or the neutral switch then the motorcycle would leak when kept on its side stand:

Checked all of them and no sign of leakage. Besides, it does not leak when put on side or center stand.

Originally Posted by ashwinprakas

On the CRF's and CB's of yesteryear they have a kicker stopper that sits under the crankcase, on the Unicorn etc it extends to be forward set pegs, the mounts are prone to crack and at times would result in leaks, but that is usually noticeable even when the motorcycle is left idle.

Quite see what you mean but the leak is almost at the center of the case. The kicker stopper is at the right side so i doubt it.

[ashwinprakas]

Originally Posted by srini1785

You mean piston rings?. could you please explain?.

If the rings are weak this would result in excessive combustion blow-by being transferred to the crank case, as a result oil would come out from the path of least resistance i.e ideally the breather.

Quite see what you mean but the leak is almost at the center of the case. The kicker stopper is at the right side so i doubt it.

The stopper extends from one side to the other.



Don't know why but that is how it is on the older CRF and CB series, but yours is older than the ones I've seen so do make sure.

Cheers,
A.P.