Ive had the sump off my car today and found a rather large lump of chewed up ali. Its about the size of your small finger nail and about 5/6 mm thick.

What would any1 recomend i do? Its a toss up between a full strip down or just hope its nothing important.

Ive just got the engine not long ago and havnt ran it yet but i heard it run in the bike and it was super smooth.

not an easy call that one.............not sure what i would do myself, but it will allways be on your mind if you don't investigate.

if i was u I would strip it otherwise you will never be sure and as they say its better safe than sorry also could be easy to fix at this stage but if you run it it could do alot of damage.
Ben

I think it may be a bit of clutch casing so i think ill have a look in there first because i want to avoid taking the head off cos itll all nead timing up again and gaskets are very expensive.

Im also going to look up through the sump up the piston bors to see if i can see anything.

Im still very tempted to do nothing but if the head has to come off then i suppose i might as well get it ported.

Any advise as to what it could be and possible problems would be much apriciated.

on my zx9 the clutch casing is made from magnesium so would be lighter than ali don't know much about any other bike engines exept mine but on the zx9 with a light and the sump off you can see quite alot. mabye just try turning it over (not starting it) and listen for any loss of compression.

Usual suspect is the clutch basket, i would whip the clutch out and check the basket for missing bits, don't panic too much if a lump has snapped off and drifted round the gearbox for a while,ally is very soft,and is unlikely to have caused much damage, if any at all. especially if it aint been in there long (if it had it would prolly have broken down to a silver mush by now, and not be a big lump)
Flush the engine out with parrafin or similar, refill with oil and a fresh filter then once youv'e run the engine for a couple of hundred miles repeat the process.
(after replacing the knackered basket of course)

I think you will be ok, big lumps are less harmful than tiny bits of shrapnel that can get into oilways and between bearing surfaces.they usually manifest themselves by jamming the gearbox.

ATB

Wadders

It may well not be anything to worry about. When I got my replacement 'blade engine, the first thing I did was drop the sump. To my horror, I found several bits of ali in the sump, one about the size of the bit you found by the sound of it. Its a long and seperate story, but due to the breaker being a total cowboy, they said that I shouldnt have taken the sump off so wouldnt entertain a refund / swap, so I was left with choice of legal action or accept the engine and hope for the best.

Anyway, whilst trying to decide what to do, I took the bits I found in the sump to a mechanic at the local Honda dealer. He took one look at them and said not to worry about them, and they quite often find shards of ali in the sump. He said they had stripped some of these engines but never found anything wrong, and said the fragments were usually remains of machining swarf that hadnt been fully flushed out when the engine was built. He mentioned that he'd even found full coils of ali in a sump before, where threads have been machined, but its more of a concern if its steel fragments that you find.
My engine went in last summer, and 2000 miles and 6 track days later, its still fine, so it may well be that your engine is OK too.

Chris

[Edited on 7/4/03 by ChrisGamlin]

Nothing much to add, as there's been good advice given already. I too would suspect the clutch, and wouldn't bother stripping the motor, unless you do the magnet test, and find significantly large particles of steel in the oil.
Just check the clutch, and if damaged, replace the necessary parts. If you can't find anything obvious, don't worry.