I have a mongoose dxr 21 speed 26 in. i want to make sure the gears shifter and the chain are right to shift right. When I shift it clicks and doesnt seem to go in correct gear.

oil the chain and get faster tires

the derailleur cable is too loose. Shift the shifter into the smallest cog, make sure the chain is on the smallest cog. The derailleur cable will most likely be very slack now. At the rear derailleur, there will be a nut or a allen bolt pinching the cable to the derailleur. loosen this, pull the cable finger tight, tighten the nut or bolt again and then try shifting again. You can dial it in using the barrel adjuster on the derailleur or the shifter.

For the gear problem.Find the shifter.Use a pair of pliers and loosen the nut where the cable is passing through the shifter.Now withe the pliers pull the cable tight.Very tight.Spray the shifter with WD-40.That should fix it.


For the front rim,tighten all the spokes.Pliers will work,but a spoke too; will make the job faster.

http://www.parktool.com/blog/repair-help/chain-installation-derailleur-bikes

Or it could be the dreaded mismatch of new chain with worn drivetrain parts...

http://sheldonbrown.com/chains.html

You have a 21 spd and you have two derailleurs, one front and one rear. To shift you must always be pedalling forward, not backwards or you can chip teeth on your chainrings and cog. To shift, remember left hand controls front, brake and derailleur, the front derailleur is what gives you the ranges, gears closest to the bike are the easiest, so, small ring it the front are your easiest range, middle, mid range, large hardest but fastest. It is best to remember that it is the number of teeth that are hitting the chain to give you the speed you want. Rear Derailleur is your fine tuner the largest is the easiest, same as above. NOW DO NOT KITTY CORNER YOUR CHAIN, SUCH AS LARGE COG IN REAR TO LARGE IN FRONT CHAIN WHEEL, AND DO NOT USE SMALL IN REAR TO SMALL IN FRONT CHAINWHEEL. The reason you do not do that is: you can stretch your chain, yes you can stretch your chain and it serves no purpose, if you are pedalling to easy change your range(front). I hope this helps you understand how to shift now. You may contact me for any further questions, I have been in business for 38+ years

if the gears are anything like mine, they are on the handel bars and all you have to do is turn them untill the arrow points to the number you want.

OK, for a beginner in the world of 18 speed bikes, put the chain on the big sprocket up front, it should be about 46 teeth, make sure it is center and doesn't make noise, if it does, adjust it just a hair either way, now, the rear, put the chain on the big sprocket in the rear, make sure the front didn't start making noise, if it did, adjust it again. You are now ready to take off, in low gear, as you start out, it is easy to pedal, soon you will be peddling air, shift into second gear in the rear only, don't touch the front. Just a little push with the thumb will make it shift, now were going faster, easy peddling, shift into 3rd, then 4th, etc, coming to a stop, down shift the back sprocket back into low gear (big sprocket) and be ready to take off again. Soon you will be shifting that thing like a Ferrari! The front sprocket, will be used for moderate terrain, wheelies, and mountain climbing, that will come later, learn how to shift the rear first. As each gear climaxes, hit the shifter, it will get smoother as you go, and keep the chain quiet, no climbing on the next sprocket or falling out of gear. Hope this helps.

hi joe,

here is a video for you in replacing the chain on your mountain bike. good luck.

http://www.youtube.com/watch?v=NMYGTc5bzNY

regards,

voodoo

My 7 speed bicycle gears are not working correctly. 3rd gear is now tougher to pedal than 4th. Something is making a clickling noise and it seems that the gears are slipping. I am thinking that something was shaken loose while transporting on a bike rack for 14 hrs. Any suggestion on fixing it other than taking it to a bike dealer?

Kevin:

I'm not sure if it's rubbing on the front or rear shifter. The front is more common, so I'll try that first. The shifter pushes the chain left (lower gear) and right (higher gear) to shift - if it's rubbing, then it may be trying to shift. If it can't be fixed by using the shifter directly, which you've probably tried already, you'll probably need to adjust the cable.

There are two ways to adjust the cable, with a barrel adjuster and with a wrench. The barrel is the piece between the cable housing (plastic tube the cable goes through, usually black) and the shifter. If it's the front shifter, it will be the one one the left of your handlebars. Try 'unscrewing' the barrel a little bit at a time. It may be off in either direction, but 'unscrewing' will tighten the cable, and since you bought the bike in the summer, it's likely that the cable has stretched and become loose since then.

Count the number of turns and try only 1 at a time, watching to see if the rubbing goes away. If not, return it to where it was by turning the same number of turns the other way.

Without knowing whether it's the front or rear, which gear it's in and which side it's rubbing on, this is my best answer. Let me know and I'll adjust my advice!

Dan