I have fear of bike shop. I can't remember of a single time where a bike shop didn't waste my time... and sometime my time and money.Cwah, Please stop wasting your money and time ,get yourself and your bike to a proper bike shop and the man there will fix this in no time. Your talents lie elsewhere. Effort without knowledge is of no avail.
I only go there to buy urgent parts in case of puncture, nothing else.
Last time I went for advice, it was for installation of a rear rack on a disc bike. The guy on the shop didn't know what to advise me and proposed me a model that didn't fit. I had to insist trying it on the bike to get him realise his recommendation was wrong.
He then recommended another (compatible) rack that was like 50% more expensive than online. So I ended up buying it online rather than a shop...
And you know what? Upon reception it wasn't compatible either and I had to hack the rack to make it fit.
So no more bike shop for me... unless you can recommend me a bike shop with competent staff somewhere in london.