I have no clue how to tighten the chain on a Moongoose XR 15 mountain bike

Hi Mitchell:
I looked at some pix of this bike and they showed a shifter. As long as the springs on the shifter mechanism are moving it as intended, the chain tension should be fine.
It's a good idea to occasionally clean the gear change assemble with a spray solvent, wipe it down, and then lightly oil it.

measure the diameter of the hole in the frame where the seat post goes. Get online and order one. They vary in size so get a precise measurement.

Change the spring to your load.

Adjust Mozo M30 Fork Suspension - Beckman Du-70 Forum

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Results 1 - 15 of 15 - Mongoose XR 150 mozo m30 front forks rebuild. A quick ...Mongoose mozo m30 forks are sponggy on my XR150 mongoose mountain bike.

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Feb 20, 2006 - 15 posts - ‎6 authors
... of a mozo m30? is it the junk im assuming came on my mongoose? ... into a halfway decent bike. and all i can get off the fork is mozo m30 ...

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I am sorry I could not find a manual for your Mongoose.
I will suggest you go to the following website
http://www.youtube.com/watch?v=2j1gSwhsVN8
You can find numerous videos for your bike repair.
in Youtube
Bud

It sounds like your chain is loose. Flip the bike over and loosen up the nuts on the back tire and tighten the nuts as you are pulling the rim back making the chain as tight as you can. You might need someone to help you pull as you tighten the nuts.

Mongoose didn't make the chainring. They're generic (like most bike parts) and have many substitutes. Determine the parameters and then go looking for one that fits.

http://www.sheldonbrown.com/gloss_bo-z.html

Other parts may also be worn, like the chain.

http://www.sheldonbrown.com/chains.html

there is a spring tesioner but probally need to take a link or two out of chain

The crank has to be removed to tighten the nut that holds the gear on. I assume that is your problem is with the chain gear on the sproket that is loose

Check the splines on the handle bar. Just loosen the "clamp" and slide the bar over to one side enough so you can tell if the are stripped or not. If they are then replace the bar, if not then reassemble and try to put a littlle extra torque on the bolt.

I have noticed with the 2 of these bikes that I have that the bars do not like to stay tight for long, they tend to work thier way loose about every other time we use them. I just keep tightening them untill the splines strip, then pick up a new bar.

Contact Mongoose for parts info at: www.Mongoose.com under "about" click ask mongoose.

Good luck.

Your bike has an automatic cam chain tensioner. There is no "adjustment". A spring supplies the tension and I will bet the spring is broken. It is possible the fiber band that is the tensioner has broken but that seldom happens.

Go to the site below where you can see a parts diagram for your specific bike. You will select the actual brand, year, model, etc., once you go to the site. Part numbers and prices are also shown. You can order parts from this site. In the event no price is shown on a particular part and/or the notation "Not Available" is in the description, the part is not in stock. www.babbittsonline.com/pages/parts/viewbybrandand/parts.aspx