Mountain Biking - Chain suck protection devices?

Anyone know about these? My friend has one on his old Trek 8000, and it seems like mine used to have one but got taken off. Anyone know where to get one and how to install it? Also, another problem may be that my chainrings are too close to the frame, which may be the reason why the original device had been removed. The cranks are Specialized Strongarm II, don't ask my why, they came like that.

Here's a pic:

Chi,


You can find anti-chain suck devices on the net on several different sites. Their was a thread a little while back about the chain suck common with Gary Fisher Sugar's. It might be worth a search of the forums, as there were several links to sites selling the devices and pictures of them in that thread. If there are markings on your bike around the bottom bracket/chainstays, they are most likely from a kickstand that was installed in that area. I would assume that they couldn't be too hard to install, though it might involve the front derailleur, which could mean that there could be some adjustments to make afterwards. I've never had a real problem with chain suck. Making sure that my chain is clean and not worn out as well as making sure my derailleurs are correctly adjusted has kept me from experiencing the problem on my current bike. I would definitely check out that other thread - I think there were a lot of suggestion/comments about them in that one.

-Moab

Chi, Colorado cyclist sells them, they are called a third eye, I cant find them on the website, but Im sure they have them.

Well, if you have an e-type front der. that'll prevent chainsuck.

Usually chainsuck is not a problem with the bike! It's rarely ever the design. Grab yourself a handy tool - the chain tool actually. You can use it to cleanly and easily remove a single link from your chain, making it about 2 cm shorter. That should fix your chain.

Also, check to make sure that you aren't in danger of busting your real deraileur from to short of a chain by putting your front gear to the highest setting while the rear one in the lowest. Do this slowly and watch your rear deraileur when you do it. Does it jam when you shift? If so, put that link back on! Otherwise try it out, it probably fixed it.

Man, I see a MAJOR problem on your Mountain Bike...there's no TREAD on the tire!

Just bustin'...

Colorado Cyclists! Nothing like a LBS gone big on the Internet, eh? They're about 5 miles from my house...the shop is TINY!

Originally posted by bikeCOLORADO
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Colorado Cyclists! Nothing like a LBS gone big on the Internet, eh? They're about 5 miles from my house...the shop is TINY!

Their catalogue rivals Victorias Secret in my house.... :lol:

The strange thing about Colorado Cyclists...it's tucked away in this VERY inconspicuous hidden shopping center. If I didn't KNOW about it from other riders - I'd never have even known where it was. I'm sure they're making a killling off the catalogue.

Most of their in-town business is word of mouth, I don't suppose that can be such a bad thing though!

Well, the reason why I ask is because it happened a couple days ago. I was at the train station waiting for the train, so I was just riding around and messin w/ the shifting. I was riding very slowly. I shifted from the big chainring to the middle one and the cranks stopped. I checked and the bottom chain had been "sucked" into the space between the large chainring and the chainstay. My friend had warned me about chain suck before, but like the LBS told me, get a new chain and your problem is fixed. Well, it happened w/ the new chain.

This problem happened w/ the old Magna as well, on a trail about a month ago. I'm just trying to protect this frame. There are some gouges on the chainstay at the same place (next to the chainrings) that the bike came w/, hence my need to worry about corrosion there.

I've heard of the Third Eye device, but apparently they mount on the seat tube, not the chainstay, so I'm not looking for that, I guess ... unless that thing can prevent chainsuck into the chainstay ...

This is the used Trek you bought a couple weeks ago right? What is/are the condition of the chainrings? If they are sharp and pointy, they're pretty well worn and could cause the chain to drop. Check also to see if there are any burrs of metal hanging that'll catch the chain and cause it to drop. If you are careful with a round file, you can file those smoother. (Cheaper to buying a new chainring). Please note, there are sometimes ramps and pins designed into the chainrings to help promote shifting. Don't grind those off! Just metal on the teeth that is there from wear.

I hope that helps. BTW, I haven't seen one in years, but there was an anti-suck device that mounted to the chainstays (where a kickstand would mount) it was bascially a flat plate in a somewhat trapezoidal shape with one jagged edge that matched the pattern of the three chainrings. Just bolted on. I'll do some searching and if I find one, I'll post the link or a pic or the source.

L8R

I just did a google search for "chain suck device" and this is the first hit: Cambria Tektro Anti-Chain Suck Device (http://www.cambriabike.com/SALE/chains/tectro_anti_chain_suck_device.htm)

L8R

Same site (Cambria) under chains I found this one too:SunRingle Device (http://www.cambriabike.com/SALE/chains_rings/SunRingle_anti-chain_suck_thingie.htm)

http://www.gvtc.com/~ngear/orders.html
I have used this with good results.


Bill F.

Thanks for the links! I particularly like the SunRingle Thingie. Anyway, here's a pic of my chainrings:

My old Trek 930 used to have a device for this that was factory fitted, although the frame had braze ons to mount it.

Actually, your chainrings look pretty good. I don't see any significant wear, and none of the teeth are pointy!

One trick I learned. When you install a new chain, you (mechanic) must push a new pin through the two links. Find the new pin on your chain. It's usually a slightly different color. When you've pushed the pin through, you have to break of half of the pin. No one does this, but file smooth the pin where it was broken. A tiny bit of the pin sticking out is enough to cause some mis-shifts.

L8R

That can't be the problem because I reused the rivet I drove out when I resized the chain. The Park tool I have did not drive the rivet completely out, so it was reuseable. Good suggestions though, thanks. I think I will go with that SunRingle deal with the Third Eye piece at the LBS. I don't like my chain coming off and scraping the BB or anywhere else. :)

dude you have the wrong bottom bracket on your bike

How can you tell? :p