Hitchcocks Forum

On draining the oil from my low milage Bullet ES I was surprised to find alli. particles in the sump.

There was nothing in the filter.

The bike runs well.

Any suggestions as to where, most likely, he particles are coming from?

Thanks

Mike

More info need . . . Actual mileage? Running-in regime e.g. max revs in gears? How large are the aluminium pieces? Have you inspected magnetic pick-up filter gauze? I suspect its probably normal swarf which appears during running in period right up to 2,000 miles or so.

Mike unless the ally has a part number on it then i shouldn't worry too much for now..

Often detritus in the motors straight from the factory.

Perhaps check again before winter or 500 miles, could be its first real oil change if previous owner didn't bother..

Just keep an ear for any changes in noise and an eye on the dip stick, assuming its an iron barrel or X..

Have a good summer riding, enjoy...

The only aluminium with moving pressure on it is the white metal bearing in the big end if your model has this type; it might be a roller bearing, so you are safe from this problem. Any other swarf will be from places that are not supposed to bear moving pressure, ie, a seized main bearing spinning in its aluminium housing and chewing it out. This swarf can get moved up to the rockers and block oil supply.
As advised above, just keep an eye on it and it might settle down after a while.

Leon, some swarf from piston skirt??

Mike just a thought incase my reply seemed flippant.

Remove the rocker bearing assemblies and just check the oil hole in each block, if it is white metal/ally then it will sure to gather there and block the return feed thus the pump worm may fail..

Its worse case, but if all clear then you can rest assured at least for the next 50 miles

nigelphoto: Yes, also from the piston, but minute glistening particles, usually only visible if the oil is viewed closely in bright Sunlight.
Which I advise to avoid doing as it would make everybody panic.

Although it may look like it, the white metal bearings are not aluminium but mostly tin, alloyed with copper, lead and antimony.

White metal bearings are (should) be made with hard material inclusions so some of the soft wears out to provide oilways and the hard parts the bearing surface proper. This is normal but there won't be much and you'd need a microscope. These bearing do bed in during the run-in.



Most likely scenario in a newish motor would be casting swarf left by the factory. I think Nigel has the right of it. Getting some swarf from bedding in during extended running in (define low mileage?) is probably normal. During running-in the engine becomes less stiff, generally due to metal being pushed out of the way and into the right places. It can take ages for some pieces to find their way into the sump.



Suggest thorough oil change with filters and keep an eye on it for recurrence.

Dunno if you've ever been inside an aluminium casting foundry. There was one at the end of our street as a nipper and one of my school mates later inherited one. You get these little webs and whiskers when you cast; they're supposed to be removed because they can break off and get in the works ...