Rhyagelle

Hey,

I got the replacement derailleur hanger a bit ago and installed it the other day now that my arm is good again. Everything seemed to be working fine, I thought, but today—feeling strong enough to do so—I took my bike out and peddled it around for a minute or two. There was a noise of some sort coming from what I can only guess was the chain. I brought it back into my workshop and looked at the rear and then the front and then finally the area where the peddles are. The sound is coming from that area. My best guess is that the chain is smacking against something? The bike seems to go into every gear except for my left hand shifter can't reach the highest number.

I do not know what is wrong with it, but I'm certain I screwed something up during the installation of the new hanger. Unfortunately I do not know how to figure this out and what to do, so I was hoping people here could help point me in the right direction? I took some pictures which I hope are helpful, but if you guys need anything else, let me know and I will get it.

Bike: Polygon Cascade 4 2020



Thank you for any help,

'02 nrs

start here; https://www.parktool.com/blog/repair...eur-adjustment /then here;https://www.parktool.com/blog/repair...eur-adjustment

Rhyagelle

Looking through his links, yea, mine looks an awful like Picture A in the first link. What a trouble this is. lol Well, I'm thankful it isn't something more serious!

I tried to take some new pictures of the RD, but I realized I wasn't sure what the jockey wheels were. Hopefully the new pictures will show this.

spelger

Jockey wheels are the little sprockets on the RD.

Could be an optical illusion but the cage looks not quite right. The chain inside doesn't look lined up with the rest of t chain. A better angle is from directly behind the RD so the alignment of the chain in the cage lines up with the chain on the cassette. We can see better if the hanger or RD is bent.

Rhyagelle

Hello and sorry for the delay. I've been out and about a lot lately looking for tools to work on the bike but it has not been easy.

Well...I can see from that image mine is nothing like that. Is that normal? It looks like it is hanging very, very low. I tried to get a picture similar to yours, but it was impossible to get the jockey wheels and the sprocket in one picture. It's a bit difficult with such a low grade camera, too.

Doug64

In the middle picture above, it looks like your chain is not even on your upper jockey wheel. If you could get some light on the rear cogs and the upper jockey wheel it would help. See if can get a clear picture of the chain going over the top jockey wheel. Also see if you can get a picture of the chain and jockey wheel when the chain is on the largest rear sprocket.

Danhedonia

p-e-d-a-l. p-e-d-a-l-l-e-d.

Rhyagelle

Okay, so...no, the chain was not on the jockey wheel all the way. When I put it on and hand pedal to test it, it shoots off the jockey wheel and then comes back to the initial position and creates the noise. I'm waiting for the images to upload, then I will post them here.

Alright, images have uploaded. I borrowed someone's phone so it should be higher quality shots with good light sources. I'm sorry some are flipped. It was the only way to get the stupid camera to focus.

Doug64

Why did you replace the derailleur hanger? If it was because of a wreck you could have bent the derailleur arm. Did you take your chain off when you were working on it? What make and model is you rear Derailleur?

Rhyagelle

I replaced it because of a crash, yes. The bike itself didn't seem to take a lot of damage. It mostly fell to one side and I flew. The hangar on it was broken and the little screw thingy went missing during the crash. I took a picture of the hanger, hopefully it helps figure this out.

No, I didn't take the chain off. I took the rear wheel off, removed old hanger and replaced with the new one and then reput the wheel back on. The model is a Shimano Tourney TX800 8-Speed, if I'm reading the specs right on the page.

Iride01 

Was the hangar the exact model you had previously? I noticed it has a slight offset in your pics. If the other didn't then that can mess up limits and other stuff. Though your offset isn't much.

I didn't understand about the chain not being on the jockey wheel. Is that a one time thing or is it happening in certain situations often?

If there aren't any parts to be replaced, this is the sort of thing most LBS's solve inexpensively. Particularly the one you might have bought this bike from.

If you are going to DIY it. Then at least go by the Shimano docs for it as well as look at the Park Tool website for some usually good videos and information.

https://si.shimano.com/#/

https://si.shimano.com/api/publish/s...001-24-ENG.pdf

https://www.parktool.com/blog/repair-help

https://www.parktool.com/blog/repair...eur-adjustment

Rhyagelle

Yes, I even asked for the product compatibility from the place I bought the bike from and then contacted Polygon. They both linked back to this one. They look identical, only the new one is way shinier.

The chain lifted off the jockey wheel a few times. I've since put it back on the jockey wheel and it seems to stay on now. The issue at the front near the pedals still persists though. It looks like it is slapping against the cage, but when I look at it, it looks like it is aligned okay. I also tested the front shifting, and I can't get the chain to shift on the front. It won't move from the smallest cog. The rear shift seems to be working just fine. I took some pictures of the cage and front derailleur.
I got some tools so now I can try the videos posted. Hopefully I can fix this. I don't have any bike shops to go to, otherwise. I will edit with results, if any.

Okay, so I tried the front derailleur adjustment video. The good news is that messing with it, I can now access the last gear for the front via the triggers and the first pedal test made it jump up on the highest gear. However, I can't get it to shift now (despite the trigger changing on the gauge thing) and although the noise is considerably less (I can also see it smacking the cage less) there's still an overall issue. Which is; can't shift front derailleur and no matter what I do, I can't get the chain to line up as shown in the video (only middle shift seems to line it up, all others make it smack into the sides of the cage).

Does this mean it's just about adjusting it some more, or something else?

Iride01 

When your front DR is in the small ring, is the chain laying on the bottom of the front DR cage? That's an issue. Don't know if it's has to do with your other issue.

If it lifts off the bottom of the cage when you put some tension on the chain by rotating the crank, then you probably are okay in that respect.

Rhyagelle

I can't seem to get it on the small ring anymore, won't shift, but right now it's not touching the bottom of the FD just the sides. I will try to shift it and test it.

No, I can't get the FD to shift to lower gears to test if the chain smacks the bottom of the cage.

Scratch that, took a bit more pedaling, but it dropped to the smallest cog and starting smacking the bottom of the cage.

ahmet sezgin

I have a similar problem but only at certain gears at my new Scott Sub cross 10. When it is in high gear ( at largest wheel at the front derailleur and at the smallest wheel at the rear derailleur) I hear such grinding noise and it feels also uneasy at the pedals. Not pedaling smoothly. This happened after I took the rear tire out for installing the kickstand. I assume I disrupted the adjustment of the rear derailleur. I tried indexing after watching the suggested park tool video. It decreased the problem (now i hear the noise of grinding just at the last three gears). But problem not totally solved. What would be your suggestion about the next move? Trying again and then adjusting the whole rear gear? and my second question, if I keep riding the bike while avoiding the problematic gears, would it be totally fine?

Rhyagelle

I don't have a suggestion, sadly, I'm a newb for these things and am still actively seeking help out myself.

Doug64

Take a look at this video and follow the steps to adjust your rear derailleur (RD). Also go to you FD and follow Park's video starting from the first step to adjust it. Don't skip steps in the FD adjustment. I really think it is something simple, but it really hard to tell without actually looking at the bike. First thing is to start with your sprocket, jockey wheels, and chain in vertical alignment, and go from there. Good luck.

Doug64

This is another source of information:
https://si.shimano.com/api/publish/s...001-24-ENG.pdf

Iride01 

You don't have to gain all your DIY skills immediately. It's okay to take it to a shop with a decent mechanic that will let you watch what they are doing. A couple of the shops around here even have their shop open so you can watch and talk with them as they work on your bike. One even has a snack bar and serves beer.

It's probably better that you start your DIY learning when the bike when it's in correct working order instead of trying to guess what that is. Like several other's posting in other threads, I think you have more than one issue.

trailangel

Post pictures

wphamilton

I'd want to get the front DR set up better before working on the back. Not that it throws your rear DR adjustment off - it doesn't, but it will be easier to see what the problems are if you solve some first.

Hard to see from a pic but I think the front DR is too high and angled to the back. The cage should be very close to the big ring, and parallel to the line of the frame (front to back that is, not aligned with the chain stay for example). I'd get that all aligned first then look at adjustments.

Rhyagelle

I'm sorry I'm late, I have been out talking to recruiters for the last few days. I've been messing with the front DR and it's mad things better, but no matter how I try to align the front according to the videos, I can't seem to get it to shift anymore or eliminate all of the noise. I will keep trying.

Iride01 I do not have any such shops around me, sadly. The closest I can get is a car mechanic place, and I do not think they deal much at all in bikes. Otherwise I would for sure bring the bike there.

spelger

All i can tell is that you are in the USA from your profile. if you are in Reno i would be happy to help out if i can.

Rhyagelle

Unfortunately I live in back watersville Kentucky, or I definitely would take you up on that offer.