2007ish Rockhopper driveline issues

[BFroelich]

Hello everyone, I’m a total noob when it comes to MTBs. I have a 2007ish model year Specialized Rockhopper that I’ve never properly maintained. As you might guess, 5 years with little to no maintenance has left its toll on the poor old bike. The biggest issue I have right now seems to be the rear hub/casette.

Here is the background story on the bike:
The old chain was rusty and stretched about 1/8" per foot and the front Deore derailleur cage was a little bent and also misadjusted. I ended up mashing the cage when the chain sucked into the it and destroyed any remnants of the original cage geometry.

I went to the bike store and got the following replacement parts:
Shimano Alivio M412 front derailleur $20
WTB Moto 26×2.1 tire $35
SRAM PC 951 9spd chain $23

Anyway, managed to install all of these parts and unloaded the driveline shifts great. However, the chain will skip under heavy load. Do you all think that this could be due to my chainrings being worn out with the old chain? Here are some pics of the chainrings:

I think I also damaged the rear hub. I don’t know if the bearings are adjustable or not, but I never did either way. The whole assembly wobbles quite a bit as you can see in the following video:

One more thing: a while ago I tried "truing" the wheel with no tools other than a spoke wrench and at some point after, I lost a spoke. This was over a year ago. considering the hub damage, should I replace the whole wheel?

In summary I have a:
-Wobbly hub
-Worn casette?
-missing spoke
-bent wheel (it’s not too bad)

So what should I do? Replace the wheel and or hub and or casette? Replace the bike? I do enjoy DIYing my stuff, are these repairs feasible for a DIYer with a few borrowed tools?

TIA!

[GoldenGoose]

Replace the spoke first. ASAP. Take a spoke from that same side off to get the correct measurements and make sure you lace them both back the same as the rest. If you don’t have a truing stand and a tensiometer you can use the seat stays as a rudimentary stand and use the tone of the spokes when plucked to know when they are evenly tensioned.

You probably don’t have actual hub damage causing the wobble. More likely your freehub, the part that attaches the cassette to the hub, is a little loose. You’ll need to take the cassette off to check this part. Going to require a chain whip and a cassette lockring tool to get the job done. The freehub is replaceable without having to dismantle the entire wheel. Check out the how-to guides on park tool’s website for directions.

The cassette doesn’t look too worn to be causing major problems. I would double check the alignment of your rear derailleur and also make sure you rear dropout hanger isn’t bent. Also run your pedals in reverse and check for stiff chain links. I have had stiff links cause chain jumps as well.

All of this should be DIY type stuff but it will probably take you a little while to figure longer to find the culprit than a shop mechanic. If you have the time and the desire to learn as you go, I say go for it! Good luck.

[glenpittman]

In addition to what GoldenGoose said, I might add that the wobble shown in the video is probably enough to cause the chain to skip under load. I would take care of the spoke and wobble on the hub first, and then see where you are before replacing the cassette.

[jeremiahbwhite]

You need a new cassette bad if this is the first time you have changed your chain. Get a shop to replace your cassette, spoke, true your wheel, and adjust your hub. It will be cheaper far than a new wheel and will last almost as long. Adjust your drivetrain yourself, DIY is difficult when you are starting from square one on the entire back wheel.

[BFroelich]

Thanks for the advice!

As soon as I can I’ll take a spoke off and get a new one. I’ll work on the hub myself I think, like Golden Goose suggested. I know I can get access to the tools required to remove the cassette. I can get access to a truing stand, but I have never trued a wheel before. I have [i:339rxt0q]Zinn and the Art of Mountain Bike Maintenance[/i:339rxt0q], he’s got a guide in there. Is truing a wheel something I should leave to a shop?

[jeremiahbwhite]

If you are asking me that question then yes. If you do it wrong you could ruin the wheel.

[Jeff Barber]

Yeah, having the chain shift under load is classic symptom of a roached out cassette. I recently switched out the (very stretched) chain on my hardtail and experienced the same thing. Popped on a new cassette and problem solved.

[BFroelich]

Sorry for taking so long to respond/reviving a dead thread; I was away from the bike this summer.

Went ahead and overhauled the hub and installed a new spoke. Everything went well except the races in the hub are roached and one of my chainrings on the cassette is missing a tooth.

Also, after running the hub and freewheel under solvent in a parts washer, the freewheel has been silent or very quiet, but functioning mechanically as it should. Should I be concerned? I might have left some solvent in the freewheel.

Thanks!

Edit:
By the way, both the freehub and hub were loose, but I couldn’t find the correct allen wrench to adjust the freehub at the bike co-op, so it’s still loose. I’ll look into it as soon as I can get the correct tool.

[GoldenGoose]

A freshly lubed freehub is usually a bit quieter so if you did relube it you should be OK. If you let the freehub dry before applying lube it should be fine.

Here’s what I’m a little worried about…

If you didn’t have the right sized allen wrench to get the freehub tightened, how did you ever get it off the hub body? Was it THAT loose?

[BFroelich]

"GoldenGoose" wrote

If you didn’t have the right sized allen wrench to get the freehub tightened, how did you ever get it off the hub body? Was it THAT loose?

Thanks for the reply! I forgot to mention that I didn’t actually get it off, which is part of the reason why I was worried that I left some solvent in it. I’m going to try to re-lube the freewheel soon (within a year haha). The freewheel is so quiet now that the driveline is louder under load than coasting.

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