If I was in the market for a secondhand Beta somewhere between 2003 an 2012, which would be the significant model year changes I should look out for? Times when they actually introduced something new and (hopefully) better, rather than just some new graphics and a bit of bling.

That is a REALLY broad request.  Often it's not the big changes that are the most meaningful, but the small ones that continually improve a particular model.  Like most of us, you'll probably have to do a lot of your own research.  You can find the different models here:

http://betausa.com/content/trial-model-history-0

youtube.com is a good place to look for info on a particular bike.

My advice would be buy the 2012

2009 was the big change, from Rev to Evo.

My advice would be buy the 2012

 

yes mine too, newest you can afford!

 

I would stay away from the `03 and the `09. Even better find a `13.

So, plus points for '09, '12 and '13. Marks against for '03 and '09. If it's not too much to ask, what are the reasons for these choices? Thanks.

In `03 they moved the engine forward and the engine was too soft. `09 was a new model, broken frames and swing arms. The `13 was just a better year so buy the newest you can afford. Just warning you on the worst years.

Thanks, All. Broken frames are mentioned again, like in my GasGas thread. However if I bought say an '09 it will be 7 years old. If no-one else has broken it by then, I don't think I'm likely to.

I have an 09 EVO that has a 2011 equivalent  frame, I think you will find that 90% of 09 EVO's have already had the frames replaced under warranty, the original 09 frames had an offset fuel filler learning to the left away from the cables, so if the filler neck is straight it has been replaced if not check with the Local dealer should still be covered by warranty if it fails,

I have an 09 evo, no problems with the frame. I was a little concerned about reported frames cracking when i bought this but having looked into it  I think it was only the early 09's that were affected, the ones with the offset rather than central filler cap as mentioned above. I believe a lot of these early production 09's went to Australia. The biggest problem with the 09 is the small,diameter rear wheel bearings, mine has a later rear wheel.

The best kept bike you can afford is your best choise. Remember, a new bike come with a waranty, just in case, imagine a used one. Seals, chain, tire... You'll probably have to invest a bit of money soon after you pick it up. So an 03 ( like mine ) in good shape is a better buy than an 07or 09 that  need a lot of care

Guy