Mountain Bike Problems.

Hi, new guy here. I went out for a ride this morning for the first time in quite a while, the bike im riding is about 5 years old, but still in good condition, never beaten or treated badly. but while riding, i had a few issues, probably issues very easy to diagnose, but im not good at bike maintenance, (need to learn, this is the only way i know how, by asking..hehe), first was while going along, the pedals would just stop, like the chain was stuck, i had to wind back on the pedals, and then carry on, sometimes having to change gears to get it going okay again, this is the best way i can explain it. the other problem is when changing gears, sometimes it feels/sounds like it misses the right gear, but eventually finds the rights one, i suspect its connected to the first problem but then again, im not sure.

ive searched around on the internet, but not found anything specifically relevant to what im looking for, so if anyone can help that would be great, cheers in advance.

If you don't have a workstand, have someone hold the rear wheel off the ground & turn the crank ... if you feel any binding, then you need to service-OR-replace your bike's BOTTOM BRACKET ...

The balky gear shifting will probably be resolved if you adjust the tension on your derailleur cable ... the cable should be lightly taut when the chain is on the smallest cog OR smallest chainring ...

Detailed instructions are available at PARKTOOL.COM.