always a lil reluctant to temp fate/repercussions and say anything on timing belts. we fit ten tones of em in a year. with smaller pulleys and higher revving engines (tho a fraction of the effort required to turn a desmo camshaft) i would deffo change on millage rather than time assuming its not to many years overdue. whats too many years?. i have a thing for Gaits. i have got it into my head that the heavier belts aint good for camshaft journals. i have not a single example of it causing a problem. its just got my wallet twitching is all.
They must have been the very first manufactures' of toothed belts ( Gates) , earliest recollection would be Ford OHC Mk3 Cortinas etc?
Early ones belts never failed but the camshafts did, oil spray bars were shit and hardness issues with the camshaft itself.
the availability of shit multigrade and the, me grandad never changed his oil so why should i attitude wouldnt of helped much either i suspect. And bearing in mind, back in the day, not many cars made it to 100k when most belts need doing these days let alone the 150k+ i see irregularly now. feck me, my panda has over 220k on it. if i mind right the pinto engine was every 36k?
So, personally I think its not just the stored bikes but where they are stored and what humidity. Ie hot dry places, versus cold and damp. My 848 was just over the 2 years Recommended but had only done 2k miles as I was actually storing it at my parents, I took the covers off to check the belts and tank they looked worse than I expected, like they were really dry and starting to show signs of having got really hot. I’d done 1 trackday
i'm told "Lazy engines" ie, low millage campers ect that only get used several times a year need their belts doing more regularly.
The CVH envine was the one that started theball rolling on timing belt paranoia, recommended by Ford at 36k miles and suffered lots of failures when ignored (one of my mated clocked his XR2 and wondered wht his timing belt snapped he wasn't the sharpest)
and the easiest of all to do. done thooosands and thoosands of em. including the repairs from belt failure.
Definitely nothing to be gained by using belts that are heavier than needed , IMO The extra tensile strength is OTT , and the damaging effect on bearings must surely be similar to over-tight belts ?
My wife's Nissan Juke needed a timing chain (yes chain) replaced at 43k miles i replaced the chain and got rid pronto Nissan are apparently renound for it
Aye , that'll be me alright .... "If it wasn't for bad luck, I wouldn't have no luck at all " Albert King - " Born Under a Bad Sign "
this is my thinking. tho i deffo left it slacker, the one time i ever used a heavier belt is the only time i have ever over tensioned one (i aint looking to damage another companies reputation) i didnt like the free movement of the belt on the pulleys either.