Chain & Jockey Wheel Service

[sleddriver]

While riding the Specialized RockHopper (SRH) around, I noticed something was amiss. The chain kept skipping, This was mostly level asphalt street. No serious hill climbing. Soon the chain just broke and I walked the bike home.

Yesterday, I soaked the chain overnight in paint thinner. Today I used a brass wirebrush to thoroughly remove any trace of old grease, wax, dirt, etc. Then wiped several times with a rag. One drop of Boeshield T9 on each link, then hung to dry for about 5hrs.

I also scrubbed clean the cassette cogs and front chainrings. Reinstalled the chain (w/o removing any links) and went for a spin. Rode about 15min. before the chain broke in the same place again.

This time I turned the bike upside down and noticed the rear deraileur jockey wheels were rough as was the cage. Off they came for a soak.

I removed one damaged chain link, reinstalled on the bike then pressed the pin back in place. Cleaned up both jockey wheels, caps, bushings and using a wire wheel in the drill press, polished the bolt surface they spin on. Reassembled with synthetic grease and then put the deraileur back together. Had a tough time though working around the tension spring, holding the wheels while inserting the bolt, then finding the hole on the other side. I need more arms for this job. Must be a better way.

With it all back together, I went for another test ride. Eeerily silent! No chain noise, quick, smooth index shifting, no chain hopping, nor grinding. This is an old chain. Probably worn out. With a good clean + new lube though it worked great.

BTW this SRH is a 21 speed (3 chainrings up front, 7 cogs in the cassette).

I've missed bike riding the past 2 weeks! Glad to have this fixed. Unfortunately, rain is forecast the next 6 days or so.....

 

[BISCUT]

How old is your StumpJumper? Sounds 15+. Great bikes back in the day. Your chain was certainly dirty but might be stretched too. Engineers ruler, measure 8 links; should be 8" pretty close to dead. Stretch in the chain will ruin drivetrain over the miles.

Ride hard and fast!!!!!

I had an old GT LTS-1 from about 97 or 98 in the garage

My, oh my has mountain bike geometry changed over the last 15 years.

 

[nthach]

Those old RockHoppers/HardRocks are the 1980s-1990s Accords of bikes. I still see a lot of them around.

You did what I would have done, though I would have used a bristle brush. T9 is a tenacious lube. I would have thrown a new chain on - Shimano shifts smoother, SRAM is easier to install(and made in Portugal if that matters).

 

[BeerCan]

replace the chain if it is that worn. A worn chain will eat up your cassette and chainrings much faster that a new one.

 

[sleddriver]

I dropped by a local bike shop. They checked for chain stretch using a Parks tool. Said it's fine. No worries. They do have a new chain for $12 and it's a regular stock item. They also had a Parks tool to remove the freewheel ($32

)

I browsed the rack of Treks & Specialized bikes. Nice but pricey. I do want to try them out.

Finally, I looked at shoes..size Euro 48! Eeek..big feet. I have to wear the skinniest socks with my present shoes. Surprising they still fit after 17yrs...

 

[sleddriver]

Originally Posted By: BISCUT
How old is your StumpJumper? Sounds 15+.
No..older..more like 27..maybe even 30.
.
Originally Posted By: BISCUT
Great bikes back in the day. Your chain was certainly dirty but might be stretched too. Engineers ruler, measure 8 links; should be 8" pretty close to dead. Stretch in the chain will ruin drivetrain over the miles. I had an old GT LTS-1 from about 97 or 98 in the garage

My, oh my has mountain bike geometry changed over the last 15 years.
Yea it has. I'll have to measure the axle-to-axle distance and compare it to the newer models.

No issue with chain stretch according to the bike mech. that checked it.

 

[Kamele0N]

Time to replace your cassette front chainrings your jockey wheels and your chain....You were cheepo for too long

 

[sleddriver]

Interesting you post a video showing the same Park tool used to verify my chain is OK...

 

[Kamele0N]

Originally Posted By: sleddriver
Interesting you post a video showing the same Park tool used to verify my chain is OK...


How long ago did you change a chain? Recently?

 

[wander2039]

Just replaced the chain and freewheel on my Specialized RockHopper. If was cheap enough also did the Trek. It did eliminate the skipping on gears. The Trek only had 2k on it but the Specialized had almost 5k that I put on it. Unknown from the the previous owner. I'd just replace vs spending all the time cleaning. Haven't decided on a chain replacement schedule yet, thinking every 2 springs.

 

[sleddriver]

Hard to know how many miles are on the original chain as I have no odometer installed. Given that, it indeed passed the Parks tool test so I'll go with that for now.

Not at all a waste to clean and relube a chain! They live a hard life riding on dirt trails in particular. I consider it regular maintainence. I can always tell it's time as the chain tells me. Afterwards, it's always much quieter and shifting is smooth and instantaneous. Positive feedback is my guide.

Pedal On......

 

[sleddriver]

Towards the end of a recent ride, I lost one of the jockey wheels! Never had that happen before. I looked around for it but no joy. Went to a local bike shop and the mechanic found a bolt that would fit the rear derailleur. Later when installing the new wheels, I discovered the bolt was about 3mm too short. Went back for another search and no joy. Went to a local REI and asked if they had anything that might fit in their dead deraileur box. He brought out a large container filled with bolts and let me look through it. I found several that might fit. At least they're the right length and the right thread size.

Still not sure how that bolt + wheel ever came loose. I've put 20+ miles on it since my earlier work.

 

[sleddriver]

One of the replacement bolts from REI's bolt-bin has solved this problem! Back to pedaling. I made sure both bolts were TIGHT.

 

[Surestick]

From the factory they have blue loctite on them.