How do you put the chain back on a Jeep Comanche bike it looks twisted were the derailleur is

I had a look at the Mongoose website.
They have manual for download.

https://int.mongoose.com/pages/product-manuals

Enter the model of your bike, or look for a picture of it.
Follow the instructions....

REgards
Geoff

Mark:

First of all, make sure that you are not over or under shifting. The chain has to be positioned exactly over the gear that you are trying to use. If you hear derailleur or chain noise The derailleur is not "in gear" and you have to adjust your shifter to eliminate noise. The derailleur must be adjusted so that the chain is parallel to the gear cluster in each gear. If the chain is twisted at all, it will skip gears. Check your rear derailleur to ensure it is pointing the chain directly at the front gear cluster. Check the front derailleur to see that it is pointing the chain directly at the rear derailleur. While you are at it... clean the derailleurs with alcohol and lube them with a light weight oil. Check the derailleur stops (small screws next to the cable clamp on the derailleur). Have the bikes rear tire off of the ground and pedal the bike with one hand while shifting with the other hand and you can see what the derailleur is doing. adjust the stops so that you can not shift the chain off of the gear cluster in high or low gear. You may have to adjust the cable length at the derailleur cable clamp, and at the adjusters on the shifter to get the exact adjustment that you want. It will take some time to properly adjust your derailleurs, but it is worth it when you can ride without your derailleurs acting up.

go google and type chain arrangement for derailer operation
regardless of the make any diagram of a derailer will be the same

Travis:
Put the rear derailleur into second gear and stop the bike before it shifts back down. Look carefully at the derailleur and you will see two small screws next to each other. These are stop screws. The stop screw for high gear may be out of adjustment, or the front derailleur is out of alignment putting sideways torsion on the chain forcing the chain to drop back into first gear.

Ask a local Bike Shop. Derailleurs for that bike are cheap. Evaluating the bike for a bent derailleur hanger and fixing it is a job for the pros. Word to the wise. Never pedal backward or roll the bicycle backward if it is the rear derailleur is not precisely aligned with a gear. It WILL rip bend or the derailleur right off.

At 46 pounds with no name components it's not worth much.

Read the reviws.

http://www.amazon.com/Jeep-Comanche-Sport-Mens-Mountain/dp/B000A2JW4I

If you learn to shift correctly this won't happen..

Google bicycle shifting technique, for example:

http://coachlevi.com/cycling/complete-beginner-guide-to-bicycle-gears-shifting/

You should NEVER run cross-chained (big-big or small-small). The drive train performs best when the chainline is as close to straight as possible. Excess sideways stress on the chain will wear it out prematurely and increase its normal efficiency.

To demonstrate this for yourself, put the bike in the same combination of gears you're having a problem with. Get behind the bike and look staright along the top of the chain. As you can see the line of the chain is a mild zig-zag where it is parallel to the bike at each gear but needs to angle across the drivetrain in between. On some bikes the chain might even come in contact with the next larger chainring when used this way.


If you can shift to the big-big combination without snapping the rear derailleur off, you're lucky. The big-big combo uses up all available chain length and the rear derailleur will be pulled toward the front of the bike, sometimes so far that it is in danger of being snapped off.

THERE IS NO UPSIDE TO CROSS-CHAINING.

As you can see, the rear derailleur is not long enough to **** up all the slack this gear combination creates. There are other combinations that would yield the equivalent gear ratio without either stressing the drivetrain or dropping the chain.

The basics of shifting are these:
1) The big ring and right side of the cassette in back are for speed.
2) The small ring and the left side of the cassette are for high torque, lower speed

Wash, degrease and scrub the chain and derailleurs with a good degreaser (like Simple Green). Dry the chain and relubricate it with an appropriate bike chain lubricant (not oil or WD-40). Shift the derailleurs to the smallest chain ring and cog on the cassette (low front gear, high rear gear) and then loosen the cable at the derailleurs, pull the cables taut and reattach them. If the derailleurs still need adjustment, here is a procedure for it:
Flip the bike over (so you can pedal the bike manually while you shift) and shift the front to the middle chain ring. Shift the rear to the highest gear (small cog). Release the cable from the pinch bolt on the derailleur. Adjust the screw marked "H" on the derailleur until the jockey wheel on the derailleur is aligned perfectly over the small cassette cog. Set the cable adjuster on the derailleur to the middle of its range (find this by screwing it all the way in and then count how many revolutions it makes until it screws out completely. Screw it back in one half of the total revolutions). Reattach the cable and shift to the lowest gear (the biggest cog). Over-shift and hold on the shifter, then adjust the "L" screw on the derailleur until the jockey wheel sits just past the last cog. You have to hold the shifter to do this. Now shift into the middle gear (or one of the two middle gears if the bike has an even number of gears) and adjust the derailleur using the barrel adjuster you previously set to the middle of its range. Adjust it so that the derailleur is sitting perfectly over the appropriate gear. Shift up and down the cassette while pedaling and in every gear, reverse pedal (freewheel) to make sure the chain does not hop. Adjust as necessary until all gears are smooth.
Now the front:
Set the rear derailleur to the lowest gear (big cog) and the front to the lowest gear (small chain ring). Disconnect the derailleur cable. Screw in the adjuster for the cable tension all the way (this adjuster is on the shifter of a mountain bike or the down tube of a road bike). Pedal to make sure the chain is not rubbing on the derailleur cage. If it is, adjust the "L" setting on the derailleur until the chain moves by without touching the cage. Now pull taut and reattch the cable and shift the front to the big ring while pedaling. If it does not shift up well or completely, hold the shifter past its normal shift and adjust the "H" screw so that the derailleur allows the shift. Shift into the highest cassette gear and keep pedaling. The chain should not be touching the front derailleur's cage when you pedal. Adjust with the barrel adjuster until the chain moves freely without touching the derailleur cage.
That should be it, unless there is another mechanical problem causing the missed shifts, like a bent derailleur hanger or damaged teeth on the cassette cogs or a bad derailleur. If it is still problematic, come back for further information.

i hope this helps
-matthew

Set your front and rear derailleurs to the middle gears. Now all you have to do is put the chain back on onto the correct chainring and cassette cog and pedal the bike a few rotations to make sure it is all clear. It sounds like you need to set the stops on your derailleurs. There will be "H" and "L" labeled screws on the derailleurs. You can set these to stop the derailleur from allowing the chain to go past the last rings. Although i can explain this, it seems best to me to send you to Park Tool's repair section (parktool.com/repair) where you can get pictures of how to do this.

i hope this helps,
matt

Starting with someone holding the bike with the front of the bike to your right proceed as follows. Shift the rear derailleur down so that it lines up with the smallest cog on the rear. Shift the front derailleur to the smallest cog on the front. This will give you the least resistance to thread the chain. Starting at the rear lay the chain over the rear cog teeth and holding the arm of the derailleur down so that the idler gears are one above the other thread the left end of the chain to the right side of the top idler gear and down through the cage. proceed with the end of the chain to the left side the the bottom idler gear and down . The left end of the chain you just threaded will now meet the right end of the chain which you are about to thread. Don't let the left end slip back the way you came. Take the right end of the chain and thread it through the cage of the front derailleur and over the smallest gear on the front proceeding to your right. It should be sitting in the teeth.Pull the right end of the chain down and arouind to meet the left end of the chain. Since you are asking how to thread the chain I am assuming that it is apart in one long length and not in a continuous loop. Use a twist tie to hold the two ends of the chain together for now. Shift the front derailleur to the largest outside gear taking care to lift the chain off the teeth of the small gear and place them on the large gear as you are shifting. Shift the rear derailleur to the largest inside gear(cog) on the back wheel taking care to move the chain again as you shift. The chain should be in a continuous loop with no twists in it that goes as I described through both derailleur cages and over the largest gear on the back and the largest gear on the front. Now the tricky part. You may need someone to help. You have to pull the chain with your left hand to move the rear derailleur cage all the way forwardand with the twist tie removed bring the right end of the chain all the way back to the rear along the left end of the chain to measure how long it would be joined up in that position. Note where the chain would meet if tight. You will have excess chain on one end. From where the ends meet give yourself two links on the excess end of the chain and where the ends will join now is the correct length. You will need a chain (break) tool to force the pin out on the excess end of the chain to remove the excess length.You have two choices for joing the chain. You can buy a pin that you can join the two ends with and when it is forced through to the mark on it with the tool you then snap the end off with a pair of pliers or you can buy a joiner link that comes in two halves that fit through the holes on opposite sides of the chain and then snap together. The forward action of pedalling will make the final snap to hold the link on. If you decide on the latter method you will notice that you will have to remove another pin from the length to get the side plates off the chain and expose both holes. This is a complicated explanation and if you haven't done this before and you don't have a chain tool it is far easier to get a bicycle shop to install a new chain as the actual chain has to be a direct match in manufacturing to properly fit your bike. If you decide to do this yourself, take the old chain in and get a new one. Make sure it hasn't been shortened as the old chain has probably been stretched and the proper method of measuring the new one is by using the bike itself not just laying the new one and the old one side by side. Good Luckand hope this helps.