Mountain Biking - Chain Tension?

i have a giant AC and whenever i drop (or just bounce on it!) the chain chips the paint on the frame (the bit between the bottom bracket and rear axle). is the chain meant to be this loose or should i tighten it (and if so, how)?

The part of the frame that your chain is hitting is called the chainstay. You need a chainstay protector which you should be able to get at your LBS for about 10 bucks.

It looks like this:
http://jensonusa.com/store/product.aspx?i=FR707Y00

thanks

Or make one out zip ties and an old tube or a bit of clear water pipe.

Or make one out zip ties and an old tube or a bit of clear water pipe.

very resourcful.
so is there actually any easy way of increasing chain tension?

Alot of people use handlebar tape. It looks alot cleaner and I want to use it, but my freakin derailluer cable has braze ons on the chainstay. :(

very resourcful.
so is there actually any easy way of increasing chain tension?
He actually got the clear water tube idea from me.:p

http://img50.exs.cx/img50/638/RaiynHardrockdrivetrainclose.jpg
http://img70.imageshack.us/img70/9563/RaiynRockhopper3a.jpg
http://img175.exs.cx/img175/7294/hopperchainstayclosecopy6pb.jpg
Two examples of chainstay guards.
Top: Section of used Specialized Armadillo Road tire with beads removed and attached with zip ties. Used on my commuter bike. Cost $0 I reused some zip ties that had been used by the manufacturer to pack new bikes that I had assembled at the shop.
Bottom: Section of clear water supply hose slit down one side and secured with zip ties. Used on my trail bike. Cost ~ $1.50 for the hose zip ties were obtained in same manner as above.
Your bike was shipped with the correct length chain. What gear position are you using when this happens?

He actually got the clear water tube idea from me.:p

Sure did. You can also get chain tensioners which are like jockey wheels and mount close to the front chainrings and also help to keep the chian on.

Your bike was shipped with the correct length chain. What gear position are you using when this happens?
usually highest gear on front, and about 6th on back (its 18spd (2 front, 9 rear)), but the chain's petty loose so i dont think that gear position really matters.

If you removed the big ring, you may be able to take out a couple of links of your chain.

Shift your bike into the biggest ring and biggest cog. Your rear derailleur should be pulled forward, not straight down or even back. IOW, the lower jockey pulley should be in front of the upper jockey pulley. NOT so far as to really put a strain or a lot of pressure on the rear derailleur, but definately in front of it.

*****Before you remove any links!******

Check the small/small combo. If the chain rubs on the upper jockey pulley and your big/big chain length check yielded room to remove a link, THEN remove a link!

Remember, a link is two (2) half links. IOW, a link is an inner half link and an outer half link together!

I'm also going to suggest this is a good time to install a SRAM power link if you don't already have one!

I used an old squash grip. I hate the look of zip ties for some reason.

I used an old squash grip. I hate the look of zip ties for some reason.
:eek:

Chainstay guard and a chain tensioner. The chain tensioner will also help you shift better and smoother than a loose one would.

thanks alot for your help.
whats a "SRAM power link" and how much do chain tensioners cost?

thanks alot for your help.
whats a "SRAM power link" and how much do chain tensioners cost?
Google (http://www.google.com/search?q=SRAM+power+link&sourceid=mozilla-search&start=0&start=0&ie=utf-8&oe=utf-8&client=firefox-a&rls=org.mozilla:en-US:official)

Kore Chain Reactors do the job nicely, if you want to hang some gear off your stay. A Lizard skins cover looks nice if you just want to protect the paint. If you're a retro kind of guy, get the Bullet Bros rear derailleur tensioner. You could probably even make one. It's basically a spring that pulls your derailleur back, keeping tension on your chain. I've got one from the 90's, and it works great for rough XC.

The best chainstay protector i have used which still looks nice is the one that this guy offered a little while ago.
http://feedback.ebay.com/ws/eBayISAPI.dll?ViewFeedback&userid=fromideastosales
Hes not selling it now but ask him about it, its polyurithane (however you spell it) strips and costs around 4 bucks. Dampens noise and lasts forever, plus it looks reasonable

no need to remove any links from the chain.
adjust the B-screw on the rear derailer can increase chain tension.

Kore Chain Reactors do the job nicely, if you want to hang some gear off your stay. A Lizard skins cover looks nice if you just want to protect the paint. If you're a retro kind of guy, get the Bullet Bros rear derailleur tensioner. You could probably even make one. It's basically a spring that pulls your derailleur back, keeping tension on your chain. I've got one from the 90's, and it works great for rough XC.

Can you photo it for me?
I've got a custom tensioner already, but do still have to half click back onto the cog sometimes when jumping. I'll build something if I can.

Also a half grip carefully zapped on the derailler knuckle can stop hits from that when on a small cog.

This build keeps the derailler pretty well solid, and helps keep the chain on the ring.

Can you photo it for me?

The Bullet Bros? Yeah, I'll see what I can do this weekend.

I've got to build a chain tensioner for my gcse. Any tips on materials to use and problems I may come up against?

Change to a SRAM derailleur. They have more tension than a Shimano, and the best part of all, they are not Shimano.

I use an old tire zip tied to the stay.