Drivetrain noise from chainline

[ADKmike]

Just installed raceface NW 30T ring on an older 9-speed bike with a 11-36 Sunrace cassette.

Took it out for first ride yesterday...had to adjust B screw a bit because cage sprocket was hitting 36T cog since now have a bigger cassette, and some playing with the wire tension barrel...but got it shifting pretty good. Still need to fine tune a bit.


Anyways - my issue is that when on the 36T cog, and even the next smallest and next one after that...the drivetrain feels kind of crunchy and it makes a bit more noise. Is this a common thing you need to live with when running a single chainring. I'm assuming this is linked to chainline being the most un-straight at the extremes of the cassette range.

Is there a way to better tune this up? The 30T NW ring has built in spacer. Do you need to add some more spacers? It's mounted on the inside of the spider.

Also, on that note - noticed chain almost looks like it's hitting tabs of spider (but it's actually not, just VERY close). Is this the way it's supposed to be since the 30T has built in spacer and it's diameter is not large enough to keep the base of the teeth, and thus the chain, away from the spider tabs?

I'll post some pics when I get a chance

Thanks

[pureshred]

AFAIK it is a common thing. I had the same problem after converting my 2x9 to 1x10. I like the simplicity of a 1x system but I can't help but feel like 1st and 2nd gear aren't as efficient as a comparable gear would be in a 2x system. Seems like there's a lot more stress and drag on the whole system with the extreme chainlines 1x creates. You could try and bring your front 30t chainring inward even more so the chain lines up better in the low gears. You'll get a super crossed chainline in high gears, but it's a worthwhile trade off.

[ADKmike]

Yeh, I just want to confirm I have it set up as perfect as possible before riding it too much and damaging brand new parts. This is my first "bike project", so learning some ins and outs of bike parts thru the process.

[jm2e]

I've been running 1x10 for a long time without ever experiencing that. Just switched to a SunRace 11-42 10sp cassette and the three biggest cogs sound horrible. Not impressed.

[steff]

The NW chainring and chain makes a tighter fit so any grit in there is going to be crunchier than usual. It'll wear itself quieter after several rides.
The chainline could be off a bit making more noise. New chain as well? The noises should also smooth out as the drivetrain wears.
When pedaling backwards in the 36 cog, does the chain derail to another cog?
Adding more spacers to the chainring may be possible but likely not the best solution. Depending on the bottom bracket setup, there might be a spacer on the drive side that could be moved to the non-drive side, which would help chainline.
The chain being close to the crank tabs is normal.

[Damian Sanders]

I've got a round 32t without spacers that I took off until I could order some long bolts, and make up some custom 1/8" (3.175mm) spacers for my new setup. I put on an oval 32t with spacers in the interim. With the spacers, my 32t round should be about a 46mm or so chainline measurement, which is the inside edge of the recommended range.

[SJG]

have you checked for chain stretch prior to the swap? A worn chain on a new ring is going to wear out the ring fast!

[grskier]

have you checked for chain stretch prior to the swap? A worn chain on a new ring is going to wear out the ring fast!

I was thinking this and chainline could both be contributing.. sounds like grime can be 'crunchy' as well...

[mntlion]

maybe a bit more B tension?

[SJG]

when my chain makes noise it is out of lube....

[ADKmike]

Cleaned old chain really well before re-installing. Lubed. Cleaned RD and all other drivechain components.

Getting a new chain for starters...mostly because I don't want to run the old chain much on new parts. Just wanted to test the thing out to make sure it was all going to work out OK before buying additional stuff, hence the cleaning and use of old chain for now.

[El Chupacabra]

maybe a bit more B tension?

I converted a bike to 1x10, keeping the standard 36T cassette intact, and used a SRAM XO crankset with a steel 28T direct-mount chainring. It was sort of a trial run to see if I liked 1X or not, and whether the gearing would work for me.

I couldn't get enough B tension on the rear derailleur -- the B tension screw bottomed out, and I had a noisy/crunchy drivetrain. I reversed it (ran the head of the screw in from the opposite side), which gave more effective length, and then it worked.

YMMV and all that.

[ADKmike]

I still have B screw length left to adjust inward. I think I've got the distance sorted - but how far should the upper derailuer sprocket be from the cassette? I just put it where it looked good and had plenty of clearance from the chain rubbing back on itself...

[bagtagley]

New chain ring with old/worn cassette and chain could be the issue.

[ADKmike]

Cassette is new too - a Sunrace 11-36T

Only chain was re-used (after being cleaned/lubed well) for a test run.

[ADKmike]

Here's some pictures of my set up please let me know if anything looks abnormal

[ADKmike]

Pics on 36T:

[steff]

Looks crunchy.
kidding, it seems ok. Chainline looks as good as any 1x setup.
If it's not working well in the big cog, check the bb spacers... looks to be 2 on the drive side(?), maybe move one or both to the other side.
Probably just needs a new chain and clean the rest again. Some fine tuning.
The space between the upper pulley and largest cog... 6mm.

[Dee Hubbs]

What are you lubing your chain with.... sand?

[SJG]

it looks like you sprinkled sand on it instead of chain lube. Clean your shit!

[ADKmike]

What are you lubing your chain with.... sand?

it looks like you sprinkled sand on it instead of chain lube. Clean your shit!

So I was thinking the same thing that it looks pretty dirty. Believe it or not, this was completely clean when the issues I'm describing were happening, and the pictures I posted are only after a 1 hour ride. That's it. I just reassembled everything, half the stuff is new (cassette/chainring) and the chain was completely cleaned and lubed. Not sure what to say, or how to avoid things getting full of dirt since, it's ridden in the dirt....but I'd love to know how everyone would be keeping there drivetrain so dirt free...seems impossible to me given the environment the bike is ridden in. In my case, for those pics, we're talking dry trails too.

Symptoms were happening right in the beginning of the ride, so I'm ruling out the dirt in this case.

On another note, I was thinking about chain length sizing. I went from a 3x9 to a 1x9. largest combo went from a 27-44 to now a 36-30. How do I determine the new chain length. Right now I just reused the one that was on the 3x9...length seems ok to me, and as you can see from my pictures, it's not floppy looking (I don't think). Is there some specific link-count for these situations, or is there some overlap? In this pic, I'm on the 11T cog...looks reasonable to me, where the cage is sitting, etc...but could just be lack of knowledge.

[grskier]

Not only the length, but the stretch...

[SJG]

post a picture of your chain in the big cog in the back.

I use a wet lube for wet conditions, and a dry lube for dry conditions. In the dry, the sand doesn't stick to a dry chain like a wet one with oil. I find I have to use the dry lubes more often though, FWIW.

[Dantheman]

On another note, I was thinking about chain length sizing. I went from a 3x9 to a 1x9. largest combo went from a 27-44 to now a 36-30. How do I determine the new chain length.

It'll work fine like that, but it's longer than it needs to be. Standard formula is to wrap the chain around the chainring (or the largest chainring on a non-1x setup) and the largest cog with no slack, without running the chain through the derailleur, then add two full links to that. On a full squish bike, depressurize the shock and do this with the rear suspension fully compressed to account for chain growth. You want to run the minimum length that still allows the RD to look like this in the largest cog:



That's a general guideline, sometimes there are exceptions. You can go full-geek here: http://www.parktool.com/blog/repair-...-length-sizing

[ADKmike]

OK thanks - my main reason for asking is because my new chain should be in the mail when I get home from work, and I don't want to F up it's length...

When you say remove two full links does that mean one set of inner and one set of outer plates = 1 link, meaning two full links is (4) pieces, two inner segments, 2 outer segments? So about 2" total?