About two weeks ago I took my bike to the local bike shop to get serviced. It was previously slipping gears under load and at the end I couldn't use the lowest gear going up hill it would just slip constantly.
I mentioned the crunching / slipping to the guy at the counter.
When I went to pick up my bike I was charge $170 bucks for two new set of brakes, replaced one bolt type thing which was apparantly shredded (called a cone or something along those lines) and to have all the gears properly set. I was also told that the rear derailleur arm was bent and this was straightened.
The bike only cost $100 from a reliable friend who only rode it ocassionally and the bike is 3 years old. So the service was comparitively costly compared to the cost of the whole bike.
In the past few days it has started slipping again under load which is what it was doing previously and it won't hold gear at all when in the very lowest 1 1 combination it always slips to 1 2. It is also very noisy when I sit in my average riding gear which is either in 4th or 5th in the rear gears. The crunching is slightly dangerous because it can happen taking off from traffic lights or when I put extra pressure on to leave an intersection / roundabout etc. when cars are waiting behind me.
The other thing is when I picked up my bike I asked about the slipping and the response was kind of like "ah, yeh, ah, that should be OK now" which sounded to me like they didn't take it for a significant ride after repairing.
On the other side, these guys are supposed to be reputable, they have been around for a few years and the bike is not a supermarket bike it was actually purchased in their shop and in their defence the bike worked and sounded like a dream when I took it out of the shop so it is possible they did take it for a test ride even if they didn't sound convincing when they said so.
I'm only an amateur so it is hard for me to describe what the problem is, it's like a split second crunch and it doesn't move down or up gear. Sometimes it feels like it is just slightly out of gear and then after riding for 2 minutes it will crunch for a second and then it will not crunch again unless I change to a different gear. Sometimes I can just sense that it isn't quite right and swith back and forward between gears. Although, when I look down at the rear gears it all looks settled even if it doesn't feel right.
I'm also not sure if it is the rear derailleur cogs where it is slipping or the gears, I have no idea because I can't visually spot it and can't tell exactly where the sensation is.
I would appreciate any advice on what my next steps should be?