Hi guys new to this site, and I dont know if this is the right forum. But here goes. I've never had a mountain bike before, or used a bike with gears. I was given an 18 speed arashi Mountain bike and a bike trainer. I dont know how to use it when it comes to the gears. From what i've read on the net there is suppose to be 3 shifts on the left and 6 on the right so you can go from 1-18. But this bike has 6 shifts on both sides with the only labelling being H for high and L for Low. Now I was reading on bike tutor that the chain should be on the middle ring but I dont know how to put it there, and when I do it manually and start pedalling it has a tendency to pop back on to the small one.
so my questions are
1) how do I use the gears
2) how do I keep the chain on the middle ring
does it matter where my chain is in the back?
I appreciate any help in this matter.