1995 Trophy 900 loud metallic clank on start up

Sprag clutch definite, sorry mate. expensive job, engine out and split in half. There is a botch fix using a spring but you still have to split the lump and it doesnt always work. The new gears are uprated and different size to originals. My sprag plus a service etc cost about £850 at a small independent shop about 5 yrs ago. Good luck.

All caused usually by a battery that is failing or holding the starter button on for too long too many times and the starter tries to fire backwards due to lack of kick, it damages a one way clutch gear

 

Early bikes, mainly with grey engines, have a cover on top of the gearbox/underneath the carbs through which the sprag clutch can be accessed. I believe a few black engines are similarly equipped. I guess they would be dated before early 1994 or thereabouts. Sorry I can't be more precise, but if you don't have the access cover fitted then you are bolloxed.
If it makes you feel any better, my Trident is a '95 with no cover, so should the same fate befall my bike then I too will be bolloxed. A good healthy battery is essential on these bikes - and indeed many others from most manufacturers (e.g. my 1972 Suzuki GT550J which completely destroyed its starter sprag - but it did have a kick starter). Triumph are not alone in this but do seem to gained a bit of a reputation, rightly or wrongly.
Good luck with it.

 

95 bikes do not have the easy acess panel on top of the crankcase. It is rectangular and sits under the carbs

 

Bad news mate - I think as Steve says the access panels went out with the grey engine casings. My 93 Trident had one but that was possibly the last year.

 

If you want to know/learn how to do it yourself go on a Clive Wood t3 masterclass. He shows you how to strip the motor to do the sprag plus lots of other things all t3 related inc valve clearances, top end strip, carbs electronics, brakes ignition etc etc. infact all known problems with t3's.
He can be contacted on 07752477738 for more info. there is some on dealers and workshop.
http://www.thetriumphforum.co.uk/threads/clive-woods-t3-workshop.7909/