embankmentlb

I feel kind of stupid not having an answer for this problem because I have been into old bikes from the time Old bikes were new. I took my old 1985 Panasonic out for the first real ride in many years and it was on some pretty hilly terrain. At least 3 times in the ride when shifting from the large front chainring to the small the chain would just skate on top of the small chaining, almost nothing I could do would get it to engage the teeth. It is kind of a scary feeling when you are all clipped, stalling out and in traffic.
The bike has a full Campy Victory group with Regina chain and freewheel that otherwise works amazingly well.
My next step is to adjust the front mech to give it more through past the small ring. I however see potential problems of loosing the chain off the inside completely.
Anyway I can say that out of all my years using almost every (now) vintage
component brand of bike components I have never really experienced this problem.
Please, I would like to hear your suggestions as to how to fix this problem.
Thanks everyone, ride on!

SurferRosa

This has happened to me a couple times with the wrong chain for the crankset. The 8-speed chain on my '87 Letour skated on and between its double (can't remember the chainset model). And an 8-speed skated between an early SR Apex double on my '82 Miyata. Both times a wider 5- or 6-speed chain solved the skating problem.

I wonder if you're using a 9- or 10-speed chain with your Victory crank or the chainring bolts are an issue.

repechage

Might as well check the chainline too.

every once in a while I have a bike that behaves this way- remove the chainring and double check for wear- burrs etc.

sometimes the front mech is not moving with authority- I remove it, clean with the adjusters backed out a bit to traverse it beyond its normal range of movement, lubricate it and any cable guides- check for dragging. I always slam the downshift - let the spring do the work.

after that is all happy, get the bike on the stand and work the gears- sometimes the cage can be massaged a bit to encourage snappy movement. Note though, these pre Ramp and pin set ups do not like to shift at high load and low RPM.

embankmentlb

Thanks for all the helpful responses!
As I hinted in the initial post, I Have been riding bikes for a pretty long time.
My first road bike was in 1982. But I seem to have forgotten so much.
The chain is a HKK Ultra 6 not a Regina as I originally stated.
I imagine that may be the cause of the problem. Would you recommend a new Sram 8 speed chain? I may also have a nos Regina oro in storage that I could use? Can you recommend something else? The freewheel is standard spacing but not really having a problem there.

SJX426 

A different rear block will not make a difference IMHO. Which sprocket is the chain on in the back when you have this problem? I would also check chain line and FD operation before spending any money. Knowing root cause first will save time and money.

embankmentlb

As you can see the chain rings have a large gap between them.

trailangel

Check that the chainrings are on correctly, not flipped. Looks like a wide spacing.
Also, clean it up, and as repechage says, shift with authority..... throw the lever all the way and let the spring shift it.

iab

You also may need to back off the lower stop.

SJX426 

LOL! If you have a mill, GREAT! No great loss with a Victory crank with its odd ball BCD!

Nice looking bike BTW!

I have the same problem with the triple on the tandem. Gotta get exactly right position with the bar end. No sneaking up on it.

SurferRosa

Yet another reason why Triomphe is better in the crankset department.

embankmentlb

It will be probably next week before I can get back to wrenching. In the meantime I have an 8 speed Sram chain on order & will find the Regina I have saved. Then I will compare all the chains and make some adjustments to the front mech and see how it goes.
One problem is that all works on the stand. I must ride about 5 miles to truly test it. It will be a fun experience.

dddd

This sort of between-rings skating on double and triple cranksets has become common on many of the bikes that I or someone else has installed narrower modern chain on.

This is usually quite easy to fix though if I just bevel the tips of the small ring's teeth as shown. This relocates the tips closer to the big ring.

The old chain you are using is likely part of the problem, it's both narrow and without any outward bulge to the side plates. Get rid of it and use something like Shimano CN-HG70, or any other good, modern 7.3mm width chain (some are narrower than that, including SRAM and some of the KMC 7-8s chains).




For some worst-case cases of chain skate, I have removed the ring and bent each tooth a half-millimeter, which was easy enough.

The SR Apex and some old Stronglight cranks had the very widest chainring spacing, while oddly enough I have ran 9s chain on certain much-older steel cranksets with no issues.

ramzilla

This is the main reason I lubricate my chains with automatic transmission fluid. I'm also a big fan of KMC 8.93x chains on all my vintage 5, 6, & 7 speed set ups.

embankmentlb

Chain update! I replaced the old ultra chain with a nos 5-6 speed Regina that I had stored away. Although I have only tried it on the stand, it looks like the skating problem is solved. The Regina has longer pins that prevent it from resting on the inner cog’s teeth. The ultra chain could just ride there comfortably.

Velo Mule

I hate when the chain skates instead of dances.

Somebody had to say it.

Let us know how the test ride goes.

gaucho777 

Glad the OP seems to have fixed the skating chain issues.

In addition to what's already been said before, I'll offer another potential cause I've experienced for the sake of future troubleshooting: Missing chainring bolt(s). I somehow lost a bolt on a TA crank, and a second small chainring bolt had started to loosen as well. As a result, the gap between the chainrings became wider and my chain would also "skate" when downshifting from the big to small chainring. Make sure those chainring bolts are tight!

KenNC

I likewise have found chain the width to be key to this problem, with 7.1mm chains (8 speed) skating, and 7.3mm chains solving the problem. The 7.3mm is actually the pin length.

embankmentlb

Update! The new Regina chain was 100% successful on the front chainrings. I shifts extremely well with no skating or hang ups.
The rear seems to be I bit more sensitive than before. Much of that may be my bad technique.
Thanks everyone!

embankmentlb

SurferRosa

"Smells like ... ... Victory."

embankmentlb

For all those who are following this story, I switched out the chain once again. Now I have an 8 speed SRAM chain. The front works great and the rear now works great. I feel very happy with the combination of Regina freewheel, Victory crank and SRAM chain. Life is good!

Charles Wahl

I hope you cleaned your freewheel and chainwheels while doing all the chain on-and-off. Bike deserves that.

embankmentlb

Thank you for the reminder. I am not good at cleaning such things.

SJX426 

embankmentlb Good to hear you solved your skating problem! What was assumed was that this problem occurred in a big rear to small front change. In other words, cross chain situation. Can you verify?

This is an interesting challenge for a 5 speed rear. The 8 speed rear on the Montello with a an 8V chain is not a skating problem but a drop issue. cross chain situations are easily obtained on this configuration with an occasional drop when in either a low rear/small front to large front or the opposite, big rear/big front to small front. Shfiting in the middle, 4th up and then change in front works extremely well, as expected. One of the reasons not to cross chain no matter how convenient it can be.

OldsCOOL

Good idea to replace the chain if you have more a few seasons of spirited riding. Chains are not expensive as a first step. I go with the Sram 8sp shortened a few links to size. I have had good results with them on my vintage racers be it cassette or freewheel, Stronglight, Shimano, etc chainrings.