curiousabe

So I'm currently running campagnolo triomphe groupset:

52-42 front
14-28 back

Got a hold of a 36t inner chainring to swap the 43 one but once swapped the chain has a lot of slack and is physically touching the fd when running small inner and largest back (36-28).

Could I get away with simply shortening the chain or is 52-36 front with 14-28 back simply too much if a gap for the triomphe rd and/or FD?

wrk101

Well first RD cage should be angled backwards with that much slack. I'll defer to the Campy experts. Cage spring tension seems off to me.

Fredo76

You need to find out your RD's max cog size and capacity, in teeth. Then you can compare those figures to what you need, which is (52+28)-(28+14)= 38T capacity needed.

If this is your derailleur, it has only 32T capacity, so won't work:
https://www.disraeligears.co.uk/site...erailleur.html

Edit: oops, that should be (52+28)-(36+14), so 30 T, so it might work, if the link is to your actual derailleur. Put it in the large-large combo, and take out as many links as you can w/o stretching the derailleur more than it can go. Then see if there is still slack in the small-small combo - hopefully not.

jdawginsc 

Chain wrap info is hard to come by for these era RDs (Victory, Triomphe, 980, 990), but I agree with the above...that RD pivot should be picking up slack and leveling out cage wise.

That said 14 back, 16 front is a lot to wrap for the lowly Campy.

990 supposedly was the best of that foursome above.

davester

Disraeli Gears lists both 32 and 28 as the max chain wrap, depending on the version. You're right in the middle at 30 so you are somewhat pushing the envelope. However, with judicious adjustment of the fore-aft position of the wheel and experimenting with different chain lengths I bet you could make it work. First thing to do is to try moving the wheel back in the dropouts. If that doesn't work, is the cage pivoted back as far as the spring or stop will let it go? If so, perhaps your chain is too long. If the spring is too slack, most of these derailleurs have a way of adjusting the tension (usually by moving the end of the spring to a different hole in the cage.

Also, another common issue is that the upper pulley hits the large cog which stops the cage from pivoting as far as it needs to. Again, this can often be dealt with by moving the wheel or changing the chain length.

If all else fails, see if you can find a smaller large chainring which will allow a shorter chain while still avoiding big-big problems.

repechage

Front mechanism is not the problem.

the prior suggestions should help.
or a Soma long cage

davester

That would be nice, but I'm pretty sure that will not fit the Triomphe/Victory derailleurs. There is an available long-cage version of the derailleur (Triomphe Leisure or Victory LX) but these are a bit hard to come by.

curiousabe

Tried unscrewing the dropout screws quite a bit and the chain got super tight when in large front and large back still too much slack while on small front and large back though

Not sure how I'm supposed to adjust the spring tension? I can only see two small adjustment screws on the front of the deraueileur:

Mr. 66

I think your rear derailleur needs to flushed out and cleaned, if that won't do the trick it is probably time to move forward and replace.

JohnDThompson 

The Triomphe rear derailleur does not have a means to change the parallelogram angle (no "B-screw"). The pulley cage is not long enough to wrap the chain when on the small ring and smaller rear sprockets while still being able to handle the large ring and larger rear sprockets. There was a long-cage version of the Triomphe rear derailleur, but it's fairly rare. It's possible that a long "Rally" cage (or Soma copy of the Rally cage) could be fitted to provide sufficient chain wrap, but unless you fabricate it yourself, Art Stump-style, the cost would be more than simply buying a modern long cage derailleur. A modern derailleur, which B-screw adjustment, upper and lower sprung pivots, and slant parallelogram will also perform much better than the Triomphe unit. Unless the OP is set on keeping the Triomphe, that's what I'd recommend.

N.B. the front derailleur should be able to handle things just fine.

davester

I don't know for sure on the Triomphe, but for the Super Record and Nuovo Record on which it is based you would remove the cage and then move the end of the spring inside the lower pivot to one of two different holes in the cage. If you remove the upper jockey wheel you should be able to see which hole the spring is currently in. From your photo it sure looks like the derailleur is not pivoting back far enough, which would be due to either spring tension or the upper jockey wheel colliding with the large freewheel cog. Are you absolutely sure that the jockey wheel isn't colliding, because it sure looks like it.

curiousabe

Not set on keeping the triomphe rd at all, what modern derailuer would you recommend that would work right of the bat?

JohnDThompson 

Something like this ought to work:


https://www.nashbar.com/sunrun-hg35-...79123?v=633398