Aweful gear shifting ...?

I have 18 gears all together (6 back and 3 front)

I can only use 1 and 2 for the 3 one (front) ... the 3rd gear never shifts unless I force the gripshift and pedal.

When I shift the back gears (6 ones) sometimes the chain falls off at the front and when it does it's a nightmare getting back on as it gets stuck. It did today.

The back are a real pain I usually keep them in gear 6 (not 1-5) all the time, 3 works too sometimes although I get alot of skipping. So for example I'd use 1 front and 6 back as my lowest.

Anyway I am going to have a good look at it tomorrow night, another thing might be to blame is that my rear cassette had bent teeth I bent them back as much as I could ... I think it has got better, but should I replace the thing?

It's a mass market bike ... the bike has been quite bad since I got it (I never got round to returning it *doh*) but I had one before (diff. bike, same 拢) and I could use any gear easy and it was rare to have the chain fall off.

Suggestions?

BTW the bike has been like this since I got it a few years ago ... I doubt it's wear and I know I should of returned it but I never got round to it. *doh*

if it was that way when you bought it.... yeah... you should have returned it.

I'd still take it back to a bike shop... and have them adjust the cables..... seems like they are not properly set.

the back cassette may also have to be replaced.

Yes, you could tweek it into submission, however,, sounds like you could end up paying more for an new cog and special tools than you would a new wallmart special. Check out www.parktools.com. They have some cool videos showing hot to do stuff. Good Luck!
H.D.

It is probably the cassette, but if you replace it, there are some rules.
-Never shift uphill
-keep the chain straight no 1-6 or 3-1 gears
-buy a bashguard

Your bike needs to be tuned up. Sounds like everything is loose and out of adjustment, and that your crank bearings may be loose too. This has nothing to do with the quality of the bike and everything to do with how it was assembled.

The BENT TEETH were not bent if they were that way since you bought it... those are called shifting ramps and helps to make smoother shifting.

Bike warranties do not include adjustments so returning it is something the store probably wouldn'r do anyway.

Here is the procedure to adjust the cables. If you are unsure about doing this yourself take it to a shop:

1) Shift the bike (pedal forward while shifting) so that the chain is on the smallest sprockets and the shifters read '1' and '6';
2) Check cable tension. There should be no slack AND no tension on the cable. If there is slack, loosen the cable anchor bolt on each derailleur and pull the cable through until there is no more slack, or let it loose until there is no more tension... the cable should be straight but tension-free. Take care not to overtighten the anchor bolts or you may break them off;
3) Try to ride and shift again. Remember to pedal forward as you shift and NEVER shift the bike standing still. If this satisfies your problem, great. If not, then I strongly suggest you take it to a shop so they can check it out.