Xtracycle Build - Pics and Questions on Chain Sag

[fatbottomedgurl]

Someday...when I am done with carpool duties and getting kids places... I will own an xtracycle.

[evangundy]

I sent an email to a friend of mine who put an xtracycle on the back of a Rans crank forward, so I knew he had long chain issues. Here is what he wrote back to me - I'll see if I can find a picture of his setup and post it. Thank you to Ian :-)
Only picture I could find is of the other side of the bike, not the chain side. (taken at the 2008 Recumbent Retreat at Ft Stevens St Park near Astoria Oregon) Doesn't show what he's done to it but does give you an idea of how long his chain is :-0
http://www.recumbentretreat.org/phot...p?image_id=551

Edna

Heya,
Well, I definitely had to deal with chain sag on my setup, considering the RANS is longer to start with.

First thought would be to make sure the chain is the right length. Should be able to shift into the big/big combo and have the rear derailer pulled almost all the way tight. That will put the most tension on the chain, limiting sag. Along with that is trying to be conscious not to use the smaller cogs when in the small chainring.

A second thing I did with my bike was pulled from my recumbent background. Just putting maximum tension on the chain wasn't enough with the loooong chainstays of the RANS. So, I got some sections of chaintube. My first thought was to just put the top run of the chain in tube, because I could tell I would have the same dragging problem she does (yes, I did look at the TE thread at work), and also across my chainstay. Having it in tube takes care of that. I then went a step further and put the bottom run of chain in tube as well. Keeps it from swaying side-to-side as much, and also keeps it a bit more protected from road grunge (which would be more important if I was in Portland than here).

The trick with the tubes is figuring how to use zipties to hold it in place, keeping it from hitting either end. Generally I'll put a ziptie around something on the bike, then ziptie the tail of that one to the chaintube. You can see something similar on many trikes that run chaintube.

The idler is an interesting idea, but I think you'd need to have something like Terracycle's setup where it can move side-to-side. And ya know, chain tube is much cheaper than Pat's wonderful creations.

So, there's how I managed it on my bike. I'd be happy to ramble off some more if I can think of something else.

[evangundy]

Here is a link to more pictures of my friend Ian's Xtracycle build up, showing better shots of what he did with his chain - hope some of this helps :-)
http://picasaweb.google.com/ian.hoff...reetXtracycle#

Edna

[kfergos]

Thank you all for your suggestions and ideas! For posterity's sake, I'm posting my solution here. I ended up going with the expensive but ideal solution, an Xtracycle-specific idler built by TerraCycle. They don't list it on their web site (http://www.terracycle.com/Merchant2/...Code=IdlersALL), but when I called and talked to a very helpful guy named Robert Johnson, he told me they had designed something to take care of Xtracycle chains. Installed it looks like this:



You can see the really long bolt with a carefully machined sleeve that serves as the axle for the idler to spin on. The benefit of this is that the idler actually moves horizontally as you shift up and down on the rear cassette, allowing your chain to stay as straight as possible. Mine seems to catch and not slide smoothly when I shift down really low, but I have only put 13 miles on it so far, so I suspect it needs to be broken in (it may also require a very light greasing, but I won't try that until I have more miles on it). I may check back with another update once I've used it more.

[sgtiger]

Very cool. Thanks for the follow-up. Something to keep in mind when we get Dh's Xtracycle built.

[Tri Girl]

That's a very clever solution! I hope that the kinks get worked out and it works very smoothly for you. I like that it can roll back and forth horizontally. Very clever!

[BleeckerSt_Girl]

Hmmm....why do they make these bikes in such a way that the chain needs special parts to 'fix' it, right out of the box?
I'm curious!

[ginny]

love the bike! The solution seems pretty perfect as well. I like the idea of the long bolt and the chain-holder-thingy being able to travel with the chain... great idea! Many happy miles to you

[kfergos]

Hmmm....why do they make these bikes in such a way that the chain needs special parts to 'fix' it, right out of the box?
I'm curious!

That's what I want to know. Their web site makes no mention of the fact that a chain at least 2x as long as normal will naturally do some serious sagging, and that most people will want to support it somehow. Why not just, say, team up with TerraCycle and include the chain idler along with the rest of the kit?

This is one of the two things I've found frustrating about the Xtracycle. The other is that the employees at Xtracycle were really not responsive to my LBS -- the LBS wrench tried calling Xtracycle several times (the board that originally came with the bike was rather battered, despite pretty decent packing, and we wanted to get a replacement), left messages, and never heard back. Eventually I had to call, and I talked to a person who sounded very helpful. But he promised to send me a tracking number when he shipped the board and never did; the new one just appeared one day at my LBS.

Conclusion: The Xtracycle itself is awesome. However, the company leaves something to be desired, and the kit could use some improvement.