I am helping a friend with an FXR Police model with 53000 miles on it that is leaking gear oil.
There is a small crack in the chamber on the left side bottom, just in front of the pulley.
Is this a common known issues?

 

Crack or Casting Flaw???
I cannot really tell..

 

I suspect a casting flaw weakness that opened from heavy adbuse. Maybe even as simple as a WOT gear shift since the main drive gear and bearing are right there.

You don't mention year.

Be sure that's actually were it's coming from. Obviously, one sees a visible flaw there. But it could ave came from the seal and got there coming down.

 

The bike is from '89. I am not sure whether its a casting flaw or a crack.
The oil are coming from the areal highlighted in red below.

 

Looks like casting flaws there if it's leaking thru.

We sealed tanks on ships with this...
CEMENT RED HAND A&B. It was a two part epoxy.

We applied it on the inside. If you clean it good enough, that may seal it on the outside.

I have an 07 Civic that had a bunch of those in the aluminum engine beside the alternator.

They were in the outer water jacket.

Just missed the recall about a year before coming thru.

It took a couple doses but I was successful in fixing them with Bar's Light duty Stop Leak Pellets.

I don't see anything for adding to oil in a aluminum transmission.

 

Did a flawfinder test.
I see no cracks. It looks to me as a casting flaw.
Would covering the area with a fair amount of J-B Weld work?

 

The dye pentrant would have trouble overcoming the capillary action of the oil.

Make sure it's seeping thru and running down.

A aluminum or most any casting will trap the pentrant in a cavity like that and make it difficult to get it off and clean up before the developer is sprayed.

Clean it up good and just hit it with the white developer to make sure its coming thru.

When your thread started, it looked like a visible crack at the bottom right.

Now I am viewing on a phone.

 

JB Weld will absolutely work. Be sure to spray with fast cleaner like brake clean or contact cleaner. When it's dry, heat with a heat gun or hair dryer which will draw the oil. Clean and heat until you're confident the oil is gone. You have an excellent adherence surface already.


I would fill the entire cavity, but do it in 4 steps. Thicker you build it, longer it takes to cure. I'd give it 2 days for every 1/4 inch to be safe.

Nice bike!