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Discussion Starter #1
Help ! My beloved Tiger 885 suddenly started clattering alarmingly at low revs - started after a short, fairly leisurely run - rattling less evident at higher revs and no clear performance deterioration. Bike is 1994. Engine has 39000 miles on it.

Wondered about the much documented DAR, but Definitely seems to come from top end - removed, checked, reassembled camshafts & chain. When I turned engine over manually with wrench on crankshaft to ensure valve timing is correct, there was a clear mechanical click at one point in the revolution - sounded to me like it could be a valve sticking briefly then freeing off ? Clattering still evident when reassembled !

Looks like a head off job, but does anyone have any ideas if there is a 'known issue' with 885 triples ? Bent valve ? Broken spring ?

Your thoughts would be much appreciated.
 

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Could be the cam chain tensioner sticking. My 1200 had an alarming click when I had it out to check the valves last time. Once it filled with oil when the engine was running the noise went away. These engines are pretty much unburstable-I had a Trophy 885 which had almost 80000 trouble free miles on it when sold
 

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Discussion Starter #3 (Edited)
'Fraid not the tensioner - got a 2nd hand chain & guide - carefully fitted and all is nice & tight. I did try a shot of oil down each plughole in case it was lack of lube. Engine sounded quieter briefly, but then just smoked as well as clattered !

Some speak of bad small end bearing on one conrod, but that would not give the pronounced metallic click I get at one point in the engine revolution as I turn it manually. It does sound like a valve springing back after the cam has opened it... and maybe the piston shutting it ???

Might put my endoscope down plug holes tomorrow to see if I can see anything. Convinced it is a sticky valve / broken valve spring. Might be able to establish this if I remove exhaust headers.

I'm reluctant to tear off head unless absolutely essential, given the exorbitant cost of a head gasket, and the apparent complications of sealing the wet liners.

Appreciate you offering your thoughts.
 

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If you find it is a stuck valve spring I think there is a way of removing the spring without lifting the head. High pressure air or something if I recall. If it is a stuck valve you should be able to see it by turning the engine with the cam cover off. I agree a clicking sound doesn't really point to a failed bearing
 

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Discussion Starter #5
Loose cam sprocket caused the rattle !

Eureka ! Endoscope showed pistons are in good nick, but could not look at valves.

Removing cam cover again revealed that the click did not come from any particular valve, but seemed to come from exhaust cam. Removed cams & chain (again) and there was movement between cam and cam sprocket - one torx screw was loose, and cam was moving a couple of mm when that screw was under pressure. Loctite & the right torque tightened it up. Also checked the inlet cam sprocket was properly torqued to the cam.

Reassembled the beast - valve timing correct & no click as I turned engine - torqued, sealed and reassembled everything - joy the Tiger purrs like it hadn't done for ages - that damn screw has probably been slowly working loose giving the little rattle that I put down to age (mine as well as the bike's !).

Went for a ride - oh.... bother, I'm riding a Tiger twin. No 3 downpipe cold. Peered through the fairing to see no3 plug lead loose - must have dislodged it when refitting the panels under the tank. Glad I carry a long screwdriver to push it down without dismantling.... and now alles in ordnung !

So here is another 'known fault' to add to the wisdom and lore of Hinckley triples - hope my experience helps someone.
 
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