Any question answered...

I've got the fear that these scratches will propagate into cracks just as I'm descending at 30mph.

Crack propagation happens at all speeds. It's the final plastic fracture which always waits until the worst possible moment.

30mph, call that descending?

Where are the scratches? Do they run around or along the bars? How deep?

Deep scratches running around the bars close to the clamp or the start of the narrow section would be the most worrying.

Could you file and polish the scratches into a gentle ripple without loosing too much wall thickness?

I've had bars snap at the clamp due to a hidden scratch and almost throw me under a bus, which wasn't fun, but they were very old bars.

Just bought a 2nd hand road bike. Left crank is 170mm and the drive side is 172.5mm.

This has to be human error on the part of the original builder?

How urgent is it that I track down a left side 172.5mm crank arm? (My legs are the same length as far as I know!)

How urgent is it that I track down a left side 172.5mm crank arm?

Not that urgent. People have been known to ride for years with accidental differential crank length without coming to any harm.

Scratches are mostly along the bar, around where the finish of the tape would be. They're not superficial, about what you'd expect from dragging a fresh blade with enough pressure to cut through a couple of layers of tape. Can't really file much - modern bars aren't that thick.

what are the little "tabs" that stick out on the side of the gear/brake lever for on older brifters such as thesehttp://www.ebay.co.uk/itm/Campagnolo-Chorus-Record-Carbon-10-speed-groupset/141657250642?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20140122125356%26meid%3D9245ced5063e4c4eae9ac3390c192257%26pid%3D100005%26rk%3D2%26rkt%3D6%26sd%3D201343360680&rt=nc
thanks

what are the little "tabs" that stick out on the side of the gear/brake lever for on older brifters such as thesehttp://www.ebay.co.uk/itm/Campagnolo-Chorus-Record-Carbon-10-speed-groupset/141657250642?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20140122125356%26meid%3D9245ced5063e4c4eae9ac3390c192257%26pid%3D100005%26rk%3D2%26rkt%3D6%26sd%3D201343360680&rt=nc
thanks

Nothing to worry about, especially with modern bar.

Er... the shift lever?

which ones as there's two possible candidates

1 - the silver/ally looking 'tab' at the top of the brake lever - pushing this in releases the brake lever forward and so relaxes the brake calipers, for removing a wheel

2 - the black 'tab' on each inner of the ergo lever body - this is the up shift button, down shift being achieved by swinging the brake lever inwards

Can I use my credit or debit card to buy from an online shop in germany who are going to want paying in € not £?

Will I be charged extra?

Yes.

Maybe, depends on the card.

Lloyds debit charge a transaction fee and screw you on the FX rate. Halifax credit cards are fine. Amex charge a few percent, etc.

Cheers, I can just use Paypal and guess that might be the easier option though I doubt their exchange rate will be favourable.

I can never find the FX rate which HSBC use, so generally go ahead and am disappointed in the result.

Paypal will gouge you. Get a credit card without a Foreign Transaction Fee. Otherwise it's 2-3% Cards that don't have a fee often have surprisingly good exchange rates.

PayPal actually worked out cheaper. Not by much but once I'd applied the 2.75% fee for the cards I have they were going to cost me more. It's a one off purchase so no point getting a new card for it.

http://www.moneysavingexpert.com/travel/cheap-travel-money#best

Trying to find out the same for HSBC. I remember seeing a non-sterling charge on a statement the other month so think they might have made the charges even worse in a recent spamming of paper at my door.

Will I be able to buy one of these in a shop in central London?

http://www.ebay.co.uk/itm/like/321287590601?limghlpsr=true&hlpv=2&ops=true&viphx=1&hlpht=true&lpid=108&chn=ps&device=c&rlsatarget=&adtype=pla&crdt=0&ff3=1&ff11=ICEP3.0.0-L&ff12=67&ff13=80&ff14=108

Paying by bank transfer to MACK for my hubs should be OK right?
Better than PayPal fees wise?

Halifax clarity is the card I use for overseas spending. Think it's generally the best of the bunch.

Shameless cross-post: is my frame fubared?

I am entering a sportive in a few weeks time and I want to give it a test run this weekend as it will be the longest ride i've done for quite a while. The map on the website is too small to be of any use so I requested a bigger map. They have sent me the GPX file. I don't have a garmin or anything, Is there an easy free website/program I can use to convert a gpx to a map or something more usefull. i've just tried maplorer.com but it seems to be very confused, either that or the gpx i've been sent is corrupt

http://www.gpsies.com