Recumbent - Chain Tension.......

Hi friends,
At least in this forum, we're all friends, don't dare venture into road cylcing's forum and let them know you're a bent'y.....

Anyway, I am assembling a bent right now and just put on the front cranks/chainrings. That chain goes to a double chainring under my seat that then goes to the rear wheel like a normal MTB. Basically the double chainring under the seat transfers the power from front chain to rear chain.

Question is, how do I get enough tension on the looooong front chain? I have a derailer in front of the underseat double ring, but I guess that's not enough, the chain still sags. LIKE CRAZY

Could I use a bigger stiffer derailer? The one I'm using is old and from an old 10-speed, the chainwheels on that dereailer are close together. Are derailers with the little wheels farther apart a better choice? Will that have a stiffer spring due to the longer arm etc.?

Thanks for being there for me in this journey to ride the best bike ever designed......the bent!

Cheers,
Dan--Ft. Lauderdale

You could try a chain tensioner. It's basically a spring-mounted idler that tensions the chain to prevent it from whipping up and down. You can make your own out of an old rear derailleur, but there are some pre-existing ones that you can buy as well.

It sounds to me like you're using a rear derailleur on the front chain as a chain tensioner. As in a Rotator? If that's the case, then you've simply got too much front chain. Take out enough links so that the chain no longer goes slack.

It sounds to me like you're using a rear derailleur on the front chain as a chain tensioner. As in a Rotator? If that's the case, then you've simply got too much front chain. Take out enough links so that the chain no longer goes slack.

You're right, upon re-reading the description, he is using a rear derailleur as a tensioner already.

In that case, remove links from the chain, or use a derailleur with a stronger spring.

What? You mean roadies don't like those of us who have bent minds? Uncool,totally uncool.bk

What? You mean roadies don't like those of us who have bent minds? Uncool,totally uncool.bk

The preppy roadie poseurs don't, because it's the cool thing to do. Most DF riders don't seem to care either way. At least we're not driving cars!

You're right, upon re-reading the description, he is using a rear derailleur as a tensioner already.
In that case, remove links from the chain, or use a derailleur with a stronger spring.Or try tweaking the 'B-tension' screw?

I figured it out last night. First the spare tensioner derailer I'm using, wasn't turned as much as it could be, and I realized I should have a little hanging springy chainwheel in the center of the long part. That'll do it perfectly. You guys are right, I have a broken dereailer that I can use the bottom of for this purpose. It'll be fine.

The problem is, I'm learning as I go. This is my first bent and first from-scratch bike build. But I'm loving it.

I look forward to seeing the results!

I would concur. I think that he just has too much chain on there. I have been tweaking my chain length on the EVOX. Even as little as an inch or two of additional chain can result in chain sag. If I were predisposed to run on the "small/small" combo (which I am not) my chain would almost be dragging on the ground. At this time it is OK in most "legal" combos, but when the weather warms up I may even take it outside and remove a few more links. (I'd do it in the house, but I want to avoid chain grease on the carpet! :) )

Cheers

Charles

Tile solves the grease on the floor problem hehehe.

Well, I also removed too many links (4) and now the chain won't go around the largest chainring DOH! And yes I popped the rivot out all the way. So can I try and put the rivot back in, or do I have to use an extra master link?

So close.....