I have an old racer (1994 Specialized Epic Allez - lugged carbon) that's in pretty good shape. I brought it to an LBS that's got a pretty good reputation and that I've used before, to change the chain and look at the front crankset as it was making a weird noise.
When I come to pick it up they have changed the whole crankset, chainwheels and all. I used to have a 34-50 (or so - I can't remember the details), and now the larger wheel is definitely bigger (52?). In theory I don't mind, as I was missing a higher gear for the flats.
But there's one problem... My chain is not long enough to use the largest chainring in front while on the largest cog at the back. I know that it's not 'the done thing' to use diagonal gears like that, but I did get into that combination by mistake yesterday, and was rather shocked when everything just got stuck.
My question is the following:
Is this a dangerous combination? Will I at some time by mistake get into the 'wrong' gear and by stamping on the pedals ruin the derailleur?
Or should I simply learn never to use that combination of gears? And instead be happy that I now have an even higher gear for those nice long slightly downhill stretches?