2h bad back

Yorkshireman2

I recently bought a used road bike which, according to all the research I did prior, is ball park the right size for me (standover height is certainly right but perhaps the top tube is on the short side forcing me to be more bent then feels natural but this is perhaps only a post-rationalisation). Well I love the bike and riding it however I'm finding that after almost exactly 2h in the saddle I'm stricken with lower back pain. This goes within seconds of stopping and standing up and leaves no lingering pain. I'm 53 so no longer supple so I was wondering if this is par for the course or if I have got the wrong size bike in some aspect? How would I know if it was the wrong size anyway i.e. how would I recognise this, what would be the physical symptoms and what body position would I be forced into? I know that I could go for a bike fitting, at no small cost, but it is a bit late for that now!
thanks everyone.

STEFANOS4784

I think this is probably down to 'core strength' try doing lots of sit-ups etc to improve your stomach muscles, i had this problem and somebody advised me to do the same and since then i only get lower back pain when switching bikes for a long period (they're quite differently sized)(the 'dale is going soon though, guna get a Bianchi 8) )

mackdaddy

I'd agree with the core strength post, but a way to get over it is to check your pedalling cadence. If you're not sure what this is do a search on cadence (might even be on a sticky).
I used to get this problem (and still do occasionally) and it is normally caused by pushing too big a gear for too long.

geerfree

You shoudn't be doing 2hr+ rides until your used to the bike position and so is your body.

But I agree, core strength could be an issue. Slowly build it up.