Although I've only had my Thema for a couple of years I'm cautious in the extreme about its belts as they broke twice during the car's earlier life. So I change the belts AND tensioner pulley bearing every 20,000 km, and check their tension every 10,000 kms.
I don't believe shelf life is a factor, but I've heard that the Bosch fuel injection could be to blame as it may shut off too quickly when changing gears and accelerating hard causing the belt to snap. 
Anyway, the belt looks too flimsy for a 16V to me, but the cam sprockets on the Thema 16V Turbo engine are 25 mm wide and can easily accommodate the 22 mm belt which is a lot stronger than the 18 mm belt currently used. This is the same belt being used on the 1.9 diesel engines. The tooth profiles are fine.
The Fiat / Lancia / Alfa part no's are: 60808683, 71719006, 7596722 & 60815140
Aftermarket makes: DAYCO: KTB220 or 94138 (173 SHP 220). GATES: 5180XS. CONTI: CT 617 (173STDN 8x22) & GoodYear G1335 (173 H8 P220)
Happy motoring!
Guy,
Thank you for that information, well worth knowing, like you I've always thought that the 16v belt wasn't man enough for the job, also very good advice about changing the tensioner bearings, many owners don't realise just how important it is to change them.
The only belt I had go on a Dedra was caused by a tensioner bearing seizing, and taking the cambelt off, I was on the way to my garage to get it changed, as I'd only recently purchased the Dedra, my 2nd auto, I was taking it very gently when there was a smell of burning rubber and the engine died, fearing the worst I opened the bonnet to see that indeed the belt had come off but wasn't broken, in the process of coming off the belt had got tangled up with the TDC sensor by the crankshaft pulley, and broken it off.
I had the garage collect the car, but when they took the head off there was no serious damage, it seems the belt snapped the TDC sensor off and stopped the engine dead before it had a chance to do any damage, there were slight dents in the top of the pistons, but no bent valves, only time I've heard of anyone getting off so lightly.
Brian
8227
