masi61

So today I installed a new Taya 9 speed gold chain on my 3 x 9 racing triple road bike. I do Molten Speed Wax so I stripped the factory lube in 2 odorless mineral spirit washes and one denatured alcohol wash before I let the chain take a bath in the crock pot with the liquid Molten Speed Wax. My crankset is an Ultegra 6603 triple and the cassette is an Ultegra 6500 12/23 nine speed. The cassette has maybe 10,000 miles on it. The cassette did not skip before.

When I departed on my ride the chain skipped several times as I climbed a slight hill. At first, I assumed that the chain might be a bit stiff from the Molten Speed Wax. I was running late for my ride so I installed the chain “hot” and did not take the time to go through and flex every link. As I installed the chain I did not notice any stiff links.

But the chain continued to skip throughout tonight’s mixed terrain ride of 54 miles. The thing is it only skipped on the rear cassette while I was in the 30 tooth “granny” chainring in the front. On the middle and big chainring, it ran smoothly - both in & out of the saddle.

So as I was riding I formulated a hypothesis that my cassette is possibly worn out. I have no idea why It seems to only be skipping in the rear while I’m in the 30 tooth chainring though.

Does the shifting symptom I have described suggest a worn cassette? I mean it does have about 10,000 miles on it. I do a fair amount of steep hill climbing out of the saddle and I weigh just under #200 . I’m a pretty smooth pedaler and have never been hard on my equipment.

I have a Rohloff HG cassette elongation checker which I bought last year but have never used. I think it is time to pull it out and evaluate the individual rear cogs where the gear slipping is occurring (it seems to be mostly in the 19 & 21 tooth cogs combined with the 30 tooth chainring where this is happening.

Feel free to make suggestions if I am missing something or do folks think I’m on the right track?

HillRider

All of your chain washing had nothing to do with the skipping. Using a new chain on a worn cassette is an almost guarantee of skipping, particularly with the most used cogs.

masi61

Thanks for your reply. It looks like I will finally have an excuse to bust out the NOS Dura Ace 7700 12/23 cassette that I have hoarded down the basement. I am a bit reluctant to use it though due to the faster wear rate on the titanium cogs. I guess I can’t just hoard my parts forever though.

BTW: how do folks dispose of a worn out cassette? Are these good for anything? If I do trash it - should I put it in the recycling bin?

rosefarts

I think you should replace at least the small ring up front too.

masi61

I don't really see much detectable wear on the chainring. I mean the skipping is occurring with the rear cassette while in the 30 tooth chainring. But it isn't slipping in the front. On my next day off (tomorrow) I will test out a different cassette and then also try my HG cog checker on my 6500 12/23 cassette. I'll post my results here. Thanks for your interest.

davidad

Why remove the factory lube? It's the best lube your chain will ever see.

masi61

I've read this many times and I believe you.... but....I really wanted to try waxing. Ultimately the factory lube will require re-application of chain lube. I am trying to keep a clean looking drivetrain and was hoping to not have to remove my chainrings and cassette for cleaning as often as I used to (which for me was at least twice a year).

In order to use the chain waxing method I am trying, Molten Speed Wax recommend cleaning a new chain to permit the best penetration of the wax. This is my second year of using the wax and my results so far have been good for the most part. I'm not sure that my chains are lasting any longer than normal though.

Advantages: 1) chain remains clean to the touch. 2) re-application of the wax is quite simple, allowing use of a 2 or 3 chain rotation when used with quick links, Park Tools chain link pliers and my mini crock pot with the Molten Speed Wax. I am on my second year of waxing and still have only used less than half of the one pound package of granules. 3) When freshly applied, the chain runs very quiet and efficient (at least for a few rides).

Disadvantages: 1) increased noise compared to wet lube. After about the 3rd ride I believe that the wax starts to flake off creating less wax to mute metal to metal contact during normal riding. The noise is most noticeable under high torque conditions such as seated or standing climbing in the smallest front chainring. 2) some would say that the application method has too many steps - this is debatable for me since things move along quickly once you figure out the sequence of steps needed and how they differ from the similarly arduous (but different process of applying wet or dry lube to a chain and trying to keep it clean.

Neutral: 1) So far I cannot tell any significant difference in chain life. My last chain, a KMC ran pretty precisely and quietly but showed greater than 1% elongation on my Park Tools chain checker after only about 1,500 to 2,000 miles of use.

But I have digressed (once again). This thread was supposed to be about a skipping issue with a 9 speed cassette. I just watched a helpful 2 minute video from "RJ the bike guy" where he demonstrates the use of the Rohloff HG cog check tool. The use of the tool when seen demonstrated like this, is not really mystifying but instead fairly straight forward.

ThermionicScott 

That'll kill a cassette. Sounds like you need to replace your chains even sooner.

Your NOS Dura-Ace cassette will thank you.

masi61

Good advice to follow, thank you!!

I have an update: I swapped out my cassette for last night’s club ride for a SRAM PG-970 in the same ratio (12-23, nine speed) as the Ultegra 6500 I was having doubts about.

And guess what? The chain skipping issue was even worse! The biggest 4 cogs in the rear were slipping with even the slightest amount of torque being applied by my riding such as starting out from a red light or getting up out of the saddle to start a climb. I completed the club ride of 54 miles while seated and while concentrating on keeping my spin smooth as butter. My riding companions were somewhat patient with me, pulling ahead on the climbs as I dropped back then allowing me to carefully do seated accelerations to catch back up.

A bike shop shop owner is in our group so I asked him (while riding). His initial response was skepticism about my Taya chain. He said he always recommends Shimano chains for Shimano drivetrains.

But then he approached me again at the next mini re-grouping spot 6 miles further down the road (a country church). He was fixing his gaze on the loop of housing at the rear derailleur. “That loop is below your quick release nut, it’s too short” he said. “That short loop is pushing your derailleur forward slightly, I would cut a longer loop of housing to relieve that pressure” he said.

Thank God! Now we’re getting somewhere. After the ride was almost completed (51 miles already completed), I took the mini-tool out of my seat bag and loosened the rear derailleur slightly. Then I took my Philips screw driver and tightened down the “B” screw (I believe that’s what it’s called). I could see the upper pulley move rearward slightly. I re-tightened the derailleur Allen bolt and rode the last 4.5 miles home, still keeping my accelerations controlled. I don’t think I had any more slippages over those last 4.5 miles, an encouraging development.

While out on the ride I was bashing my own (gold) Taya Nove-91 chain, thinking that it had excessive slop for a new chain. It was certainly flexy side to side. So once home I had to check it with my Park Tools chain checker. It tested as new! Elongation was zero. I thought the chain was shifting well except for that gnashing, horrifying crunch I was getting on the climbs.

If you’re with me so far - thank you! My mechanical mysteries are often puzzles such as this. Tomorrow evening I plan to cut a new, longer loop of compressionless housing to the rear derailleur and outfit a new inner wire (since the one on there has been trimmed to fit the existing housing). I look forward to having my 3x9 road racing triple optimized so I can go to battle with my riding companions in the hill country near me once again.