so every time I would ride this bike it would feel like the cog would get stuck st some point then you would hear a crunch and it would fall out of fears or the chain would come loose.
On top of that the bike would seem very slow when it felt as if it was running smooth.People on cheap looking bikes would fly past me a lot of the time and I felt like I had to put a lot more effort into getting my speed up than other people (I'm fit and healthy)
How do I fix it what parts would you recommend ?
Btw I took it to a local bike shop last year and they tried to rip me off so I don't really have any where to take it to now.
Clean and lube your drivetrain. Also look up how to adjust your front and rear derailleur.
>>1215420
http://www.parktool.com/blog/repair-help#
if the guide isnt clear look up a youtube video.
>>1215420
well it sounds like >>1215433 is right.
Without any other info it sounds like you have your derailleur gears misalligned. So you are in a shitty gear and when you try to switch gears the chain slips off and then catches again. And if the chain is on the small end on both sides (because it slipped off the big side and didn't go up a size on the other one) then you end up with a slack chain and it comes loose.