Losing wattage? Check your jockey wheel on the derailleur

[weisan]

Warning : long winded story. If you are short on time, jump right to the conclusion in the last line or so. :D


Rode my titanium bike Merlin Agilis with two pals this past Saturday. One of them is Andy, a good friend of Spoke, whom I knew to be a strong rider based on my first ride with him long ago on a local group ride. He rides a beautiful red Ottrott built by Kelly Bedford. The other rider is Paul whom I met for the first time. We met up at Nelo's, a local bike shop in town. I don't normally ride with this group but most of my riding buddies had gone out of town to do the Easter Hill Country Tour in Kerrville so I thought what the heck, let's just go and try out a new group. So I rode 18 miles from my house to the start point, thinking that the route they normally do will take me back to home. As it turned out, they decided to change the route when I got there. No biggie, I figured I will just peel off at a certain point of the ride when it's somewhat in my vicinity.

Throughout the ride, I had a hard time keeping up with these two riders. I mean, I knew they were strong and we were going at a good clip in the 22-24mph range on average but I knew at my current fitness level, it shouldn't be a problem. But here I was, finding myself constantly in the back foot. I was puzzled and thought maybe I rode a bit too hard yesterday with my buddy Michael in our pre-weekend shakedown ride. The roads that we rode on were undulating and curvy, a lot of slowing down and power up. I was running out of steam and got dropped a couple of times. To make things worse, I broke my chain in the middle of it. Luckily, Paul carried a chain tool and had a spare quick link. That saved the day and I was able to do a quick roadside repair and got back on the ride. Shortly after that, we reached the intersection where I had to peel off and start heading back my direction. Even though I was riding at a much slower pace on my own, I still found it hard to even maintain a decent speed. I finally got home and had to put the bike away quickly so I can get to another appointment.

I finally got around to doing a bit of post-ride cleaning on the Merlin earlier this evening. Was turning the crank around to wipe the chain and found that there was quite a bit of resistance. Took the rear wheel off and have a closer look at the drivetrain to see if I can find where that resistance was coming from. Still couldn't tell. So I decided to take apart the chain and inspect individual components. When I got to the derailleur, I had a shock. The upper jockey wheel was completely stucked and barely turning. Whoa! That would rob me a couple of watts, don't you think? :D

It's an older LX derailleur that I got from the co-op a while back. I removed it from the bike and replaced it with another spare XT derailleur that I have around. Before that, I made sure to check the jockey wheels and that they were spinning freely, they were. Put everything back together and spin the cranks again, wow, what a difference, it's like night and day.

What's the moral of the story?

Don't underestimate the power of a small little jockey wheel, it can make or break your ride.

I guess this gives me a bit of appreciation for ceramic bearings. I don't think I will go to that length but from now on, I will be more watchful of my drivetrain and making sure that everything spins up nice and smooth.

[marciero]

Hmmm.... skeptical. You sure it's not loss of power from all the weight you lost?? ; ) Seriously, was it that stuck? You could just have been having an off day. Another thing is the dynamics of very small groups, three people in this case, including two people riding together for the first time. Sometimes the tendency is to push the pace either due to simple ego or because no one wants to be holding the group back. There could have been some of that going on. But more importantly, what is an XT/ XTR rd doing on an Agilis?? Sorry, couldn't resist.

[oldpotatoe]

The upper jockey wheel was completely stucked and barely turning. Whoa! That would rob me a couple of watts, don't you think?

Yup but make for a day when you couldn't 'keep up' when normally you do? Doubt it..and broke yer chain? That's more unusual than a sticky but not noisy(?) pulley.

[benb]

I'd probably believe it if it's really "stuck" and seems like it takes noticeable force with your fingers to rotate it.

But yah myriad other rider factors could easily be bigger.

[ultraman6970]

That xplains why I suck at riding then.

[fignon's barber]

There is nothing in the universe as dense as the black sludge that builds up between the pulley wheel and the inner surface of the cage.

[weisan]

Some of you pals just simply cracked me up...

I started this thread as a cautionary tale to others who might run into the same issue but not thinking to go look at something as inconspicuous as a jockey wheel.

And yet, I am being misconstrued as trying to come up with excuses for poor performance.

That explains a lot about human nature and what goes on around us in the world today.

You are damned for speaking the truth or standing up for something and you are damned if you don't. Either way you can't win. No wonder our younger generations are skeptical about everything and have no idea what is right and what is wrong anymore. They are totally confused....by us.

[bigbill]

I keep a new pair of 11S campy pulleys in my toolbox next to the wavy washer and UT bearings. They've been there since 2010. I used to wear out a set every few years on 8S Dura Ace but they'd get noisy first. I've gummed up a few but could typically flush them out with a bunch of solvent type lube such as pro-link. If it's bad enough I disassemble and clean but then there's the risk of not putting it together right or tight.

My gravel bike has an Ultegra 8000 rear derailleur, that thing is so easy to clean out.

[Kontact]

Some of you pals just simply cracked me up...

I started this thread as a cautionary tale to others who might run into the same issue but not thinking to go look at something as inconspicuous as a jockey wheel.

And yet, I am being misconstrued as trying to come up with excuses for poor performance.

That explains a lot about human nature and what goes on around us in the world today.

You are damned for speaking the truth or standing up for something and you are damned if you don't. Either way you can't win. No wonder our younger generations are skeptical about everything and have no idea what is right and what is wrong anymore. They are totally confused....by us.

The skepticism comes in part from the vast difference in the amount of energy you are putting into the drivetrain and the amount of drag a plastic pulley on the end of a spring loaded arm can resist that without breaking something.


But maybe it was dragging enough to bother you without yanking the derailleur up into the cassette. Did you figure out why the pulley-pal isn't moving?

[gone]

What's the moral of the story?

Don't underestimate the power of a small little jockey wheel, it can make or break your ride.


Breaking news: bicycles require maintenance.

Film at 11.

;-)

[weisan]

Did you figure out why the pulley-pal isn't moving?
Yes and no.
not entirely.
The most straightforward explanation is that the bolt on the pulley was over tightened. But how it got there, I don't know. It was fine the last time I rode on it about a week ago.

Want to do a simple test yourself?

Go tighten that bolt and see how much resistance it creates.

Seeing is believing.

[Cloozoe]

I am being misconstrued as trying to come up with excuses for poor performance.

That explains a lot about human nature and what goes on around us in the world today.

You are damned for speaking the truth or standing up for something and you are damned if you don't. Either way you can't win. No wonder our younger generations are skeptical about everything and have no idea what is right and what is wrong anymore.

Wow - really glad I happened to read this post! I'm very concerned about the state of the country today and had my own ideas about the cause of the problems, but never in my wildest dreams would it have occurred to me that all the world's ills can be laid at the feet of the Paceline Forum members who teased Weisan about his jockey wheel. Thanks for straightening me out.

[dbnm]

And then try these
https://www.kogel.cc/collections/ceramic-derailleur-pulleys/products/the-not-for-instagram-pulleys-1

[skijoring]

Oh man, if you are using a derailleur from 1993-94 on that bike then what is the expectation? :)

[weisan]

Haha...cloozoe pal, you can tease all you want. I just want you to know your response is very predictable and typical. That's why these types of discussions or conversations typically never go anywhere or solve anything.

[benb]

Forget the pulley you have scratches on the derailleur, each one of those scratches has got to be costing you at least 20W, but scratches are multiplicative, not additive, so it's gotta be at least 400W that's costing you.

All in good fun, I do believe you that if the pulley is stuck it's going to rob energy, but it does also seem that the derailleur should have been sucked backwards/broken by the chain if it was really stuck badly.

My chain on my gravel bike is pretty nasty right now and I've had a few times lately it actually did start to pull back/suck up due to the resistance/gunk.

[cadence90]

Martyrdom by way of jockey wheel...it's apparently a tough, tough life while it lasts.
.

[FlashUNC]

If it was that heavily jammed up, how did it not snap the derailleur arm off? Surely had to be more resistance than the spring could hold off against while you're pedaling.

[weisan]

Back to our regular channel....


Mystery solved.

On closer examination and upon Kontact pal 's prompting, I think I know what's going on.

The lip on the outer cage was pressed against the jockey wheel.

It!s entirely my bad.

This was an older derailleur that I was trying to salvage from the parts bin in the co-op and put back into service. Yeah, I should know better. The problem it had before was the lower jockey wheel had already worn out. So I replaced it with one that I took from a broken deraileur. Apparently they are not compatible in specs. I thought they were but they are not.

So, this is all my own doing. I should be given 100 lashes and sent back out to ride another 100 miles on said rubbin' non'-rotational jockey wheel as penance.

[Blown Reek]

Garbage in, garbage out.

[Kontact]

Yes and no.
not entirely.
The most straightforward explanation is that the bolt on the pulley was over tightened. But how it got there, I don't know. It was fine the last time I rode on it about a week ago.

Want to do a simple test yourself?

Go tighten that bolt and see how much resistance it creates.

Seeing is believing.

Zero. The pulley bolt tightens down on the bushing or center of the bearing. The pulley rides on the bushing without being affected by how much the bushing is being clamped.


You should take a pulley apart. Seeing is believing.

[lemondvictoire]

Looks like maybe on a ride the bolt got loose and was tightened down real good.. too good.. little too much of the bolt thread exposed... Should of carefully tighten with thread lock blue.. I remember they came with some white stuff on the bolt threads.....

[dddd]

I've bought more than enough used bikes to have seen pulleys that had that same something going on, where the chain would make noises from such high rotational viscous drag.
Something that was used for lubrication surely, but it would easily persist through a first ride or two before being discovered.
Most of the older Suntour and Simplex pullies had much larger-diameter pulley bushings that could cause the most incredible amount of drag.

Check out some of the bikes that get donated to thrift stores, just try pedaling through one revolution of the cranks, lol. I've ridden a few of these home after jogging to said store, the ones whose tires held air.

[weisan]

Thanks for chiming in, pals.

This really is nothing more than a failure on my part. I thought I managed to save and get an old derailleur to work again but I should have known better. I have had many success in the past with salvaging thrown away parts and extending their useful life. This is not one of them.

I knew the lip was cutting too close and actually tried to bend it outwards to create space. And then I made sure to tighten the bolt just enough to keep the jockey wheel in place without binding. It was not the most ideal situation but I probably messed with it long enough to the point that I thought it was satisfactory and working okay. And it did for a time, actually quite wonderfully in the last couple of rides before something happened along the way where the bolt got tightened just enough to cause it to bind.

I think this thread has ran its course. Before I leave it alone, I just want to say that it's easy to condemn any old and used parts as garbage but with my right hand on my chest, I can honestly say that I have had success with redeeming some of these old garbage and giving them a second leash of life where they had performed admirably. I guess it's a mixed record. You win some, and you lose some. but there's enough win to encourage me to continue this path. I should be more aware of my limitation as a fixer. I am not the best in this area but I like to try and experiment and when it works, it feels great and gratified.

[rustychisel]

Wouldn't happen with Campagnolo-pal. :banana:

[Tony]

Looks like maybe on a ride the bolt got loose and was tightened down real good.. too good.. little too much of the bolt thread exposed... Should of carefully tighten with thread lock blue.. I remember they came with some white stuff on the bolt threads.....

I've seen the bolt threads exposed on many different high end derailleurs. The bolt tightens down on the bushing, leaving the pulley to spin freely. My first reaction was that maybe someone used a different bushing in this der, knowing
Weisan most likely bought it used.

[CSTRider]

I was just convinced Weisan-Pal was going to call April fools after getting everyone's particle physics theories on why he was losing kilowatts of power through his derailleur pulley ... :hello:

[TonyG]

I've never had performance issues in my Jockeys.... yet :eek:

[weisan]

Me either. That's why it's the last place I checked. Again, this is a perfect storm scenario. I doubt it happens very often.

[TonyG]

Me either. That's why it's the last place I checked.

:hello::p

[OtayBW]

Me either. That's why it's the last place I checked. Again, this is a perfect storm scenario. I doubt it happens very often.
Somehow, I don't think they'll be making a movie out of this...

[oldpotatoe]

Me either. That's why it's the last place I checked. Again, this is a perfect storm scenario. I doubt it happens very often.

I wanna hear how you broke a chain, on a road ride, in dry conditions..that shouldn't happen either...:eek:

But I know I won't see an answer here...:)

[duff_duffy]

Seriously just spray it for 4-5 seconds with WD40. Does not matter the problem, this fixes all. Your wattage will increase by 20 fold.

[weisan]

Seriously just spray it for 4-5 seconds with WD40. Does not matter the problem, this fixes all. Your wattage will increase by 20 fold.

Already tried that first thing.
Didn't help.

https://edrugsearch.com/wp-content/uploads/2017/07/windex-uses.png