sjanzeir

Just finished upgrading my Dahon Hemingway from factory 9-speed to 11-speed..

Components, all brand new:

- L-twoo A9 shifter and rear derailleur (factory 9-speed group was L-twoo A7, rebranded as Dahon; was absolutely reliable and worked great, so decided to use the same off of Aliexpress)
- Sunrace 11-speed cassette, 11-40t
- KMC chain, 11-speed
- Wolf Tooth narrow wide chainring , 130mm BCD, 52t (knew I shouldn't skimp on these )
- CDHpower crank arms, 165mm arm length (Chinese, but definitely not cheap at $75 off of Amazon.sa Prime, delivered to door)

Here's where the chain ended up:





Is it too long or just right?

Andrew R Stewart 

"just right" is a determination made after the system is used. Have you used it yet in real life?

Generally there's a range of a few links between too short and too long. Where within this range your bike's best set up is found by trying. I usually err on the long side as one can more easily shorten a chain than lengthen it.

The photo shows a chain that is not too short or long but that's all I can say from long distance. Andy

Kapusta

Looks way too long to me. But it will still likely work fine.

Look at the Park Tools website for how to size a chain (Big/Big plus 1 or 2 links depending on how you are counting)

KerryIrons

If the chain is not hanging loose in the small-small combination, then it is not too long. If you can shift to the big-big combination without duress, then the chain is long enough.

zandoval 

So far looks good, your right in the sweet spot. Some times finding the right chain length can be tedious. Especially when resurrecting and old bike with Parts Bin components. Just beware of the short or too long chain. It can really wreak a nice bike.

Camilo

Why do you think it's way too long? The rear derailleur cage has no problem taking up the slack on the small sprocket, in fact it could take up more.

sjanzeir

Andrew R Stewart I haven't actually taken the bike out of the street yet, but I can report that after I've made the proper H/L adjustments (really only the H side needed to be curbed in; the L side was already spot on out of the box... Or plastic Aliexpress bag ) I could run up and down all the gears with no problems.

With that being said, L-twoo say that this derailleur can take up to 42t, but I had to screw the B screw all the way in just to keep the upper jockey wheel comfortably clear of the big cog.

Also, gears 4 and 5 are particularly noisy, which I find odd given that the chain is straightest in these two gears!

Kapusta

Yes, it looks like your RD has a lot of excess chain wrap capacity for your setup, so there will be a wide range of chain length that will work. And yes, you could go longer and it will still work.

However, in my experience, it is better to minimize the excess chain bouncing around when going over bumps. Less likely to hit the chain-stay, and less likely to drop a chain. I might make less difference for your bike (can't tell what it is, but it looks like a commuter or touring bike?) but it makes a difference on MTBs, especially if the RD is not a clutch type.

If this is a 1X setup with plenty of excess wrap capacity, then maybe I would not go as short as big/big plus one (perhaps I'd go one link longer). But unless there is something in the setup instructions for that RD that says otherwise, I'd shorten it.

That's my $0.02.

Kapusta

This is another reason to consider shortening the chain. As you pull the cage down, the jockey wheel moves away from the cog.

smd4

I'd say this is pretty bad advice--if not dangerous. Out on the road is the last place you want to test out your repairs--including whether or not your chain is the correct length. This is what bike stands are for--to determine if there will be a problem before you take the bike out on the road in "real life."

Kapusta

Yes, if that were all he had written, that would be pretty bad advice. However, that’s not all he wrote, which is why you’re supposed to read the rest of his post.

smd4

I read the rest. What did he write later that changes what he wrote in the first sentence?

This is a pretty definite statement that wasn't modified later in the post.

Kapusta

From his post:

Generally there's a range of a few links between too short and too long. Where within this range your bike's best set up is found by trying.

Seemed pretty clear to me.

And FWIW, the OP is clearly within this range.

easyupbug 

I would ride that bike and assess shifting, no worries.

smd4

I would assess shifting on the stand, then ride the bike. No worries--for real.

easyupbug 

You must have missed his comment: " I could run up and down all the gears with no problems.", which sounds like assessing the shifting to me.

smd4

Yep, missed that. He did the right thing.

Camilo

It's not my my bike. But I still don't understand what you see in the pictures that would lead you to think that the chain is too long. When it's on the big sprocket, it looks to me like the derailleur wouldn't like a chain that is shorter, there isn't much curve as the chain wraps through the pulleys. Is that what you're looking at thinking that it could be shorter and not over-tax the RD cage?

It is a 1X as in the OP: "Wolf Tooth narrow wide chainring , 130mm BCD, 52t "

Kapusta

Unless there is some thing unusual about that particular RD, it would have no problems with a chain a bit shorter. That is not even close to maxed out on how much it can extend.

As far as WHY i would consider shortening it… I gave reasons in two different posts.

Andrew R Stewart 

so I read this post, to my reply to the OP, this morning as I was about to leave for my volunteer stint at our regional non profit bike recycler. I had quickly started a response and deleted it due to not having time to really digest and respond to what i was claimed to have promoted, unsafe mechanical procedures. 12 hours ago I was a bit miffed at this and my initial reply wasn't too nice. But a day's work and bike ride and I am past most of this...

Of course all the possible work that can be done without test ride feed back should be done before that test ride (unless the ticket or mechanic's judgement calls for a pre assessment/servicing test ride). To claim I said otherwise is not right. To suggest that a mechanic's after service ride is not the right way to confirm actual performance is missing a vital point. That the work is only valid when the repair stand and real life rides agree. Would you expect your customer/friend to be the gunnie pig after your work? To not consider a test, and the feedback loop it offers for further tweaking, is poor procedure in any field is just lacking credence. There are a number of differences with in stand functions and in the field ones (brake squeals come to mind fast). The after service test gives the mechanic the real life feedback they need to more fully understand that bike's issues and abilities to be "tuned" better. Some call this learning and striving for best performance.

I could go on about the lacking of "turn screws by the numbers" manor of instructions and the lack of basic understandings of method and procedures but these are for another thread. Andy

smd4

I apologize if I misinterpreted what you wrote, or what you intended. But leading off with the statement "'just right' is a determination made after the system is used. Have you used it yet in real life?," implies that this is the initial test that will determine proper chain length.

I can only envision someone getting on their bike after "adjusting" their chain length, heading for a hill, launching into low gear and lurching forward as their derailleur explodes because the chain was too short. As for chain length, I still believe "just right" is a determination to be made before the system is used. Had it been me, I would have left your statement for the end of your post.

But again, I apologize, and thanks for your clarification.

Andrew R Stewart 

Thank you for your reply. I am not a natural writer (dyslexia and a very analog way of doing things) so I usually could better describe what I am trying to get across. I had hoped that highlighting "just right" was enough to differentiate from "works OK". Guess not... Andy