kbjack

I've had my Austro Daimler Inter 10 out just a few times this summer. I love the bike, but it's funky French nature is starting to get on my nerves.



Riding around town it started to make a kind of mechanical clunking sound, which at first I attributed to the freewheel. After replacing that I'm still getting the clunk...fairly rhythmical, only when pedaling and only when seated on the bike--doesn't do it in the stand. My next best guess is it's gotta be coming from the BB.

Now this would be small potatoes if it weren't for the fact that it has a pre-1983 stronglight crankset

--which means a non-standard crank bolt size and threading...which means I can't do the removal myself without investing in this fun little number:


My LBS did me a solid about a year ago and bought the tool to do a bb overhaul. They found that the cups were a little pitted, but I figured I'd have a hell of a time replacing the thing, so we just greased it up and put it back on. Now I'm questioning my wisdom, but at the time I just wanted to get it on the road.

Anyway, all this is to say: help! Here are the questions I have:
1) Is it for sure the BB making the sound? (Based on the pitting I have to think it is, but I'd love it to be something else.)

2) Is it worth replacing the BB or should I just ride it infrequently--I don't ride it that much anyway--and put up with the clunk?

3) Now that VO has their French-threaded bb https://www.velo-orange.com/grcrufrthbob.html , I'm tempted to replace mine. But theirs has a JIS tapered spindle--will this work on the Stronglight crank? Also, anyone know the proper spindle length for a Stronglight 49 double crank?

4) Other options?

Thanks!

CV-6 

Okay, first the fact your components are French has nothing to do with the problem.

It is not for certain that the BB is the culprit. Is there play in the BB?

It may sound strange, but I see springs on your saddle. Look there.

kbjack

No, you're right--I'm not blaming the problem on Frenchness. I'm blaming Frenchness for making a potential fix much more expensive.

That's an older picture--that saddle is no longer on the bike. But I know where you're going on the recommendation. I don't think the sound is seatpost/saddle related. That said, I can't find any noticeable play in the bb.

dbakl

Is the crank arm striking the front derailler, or is the front derailler rubbing on the guard?

Might you have a tight link in the chain?

Pedals can make noise too.

Any play in the cranks?

Many years ago I had a noise on my bike that was driving me crazy. Never could find it in the stand, but was always there riding.

Turned out to be the toe strap button hitting the pedal with every revolution...

prettyshady

I emailed Jim stein who produces the 23.35 crankpulling tool (jim@jastein.com) and he posted one over to france. Turned out to be inexpensive and very useful

kbjack

Hmm, good suggestions. I'll check these when I get home. I assumed a bearing or pawl related noise rather than something simpler because of the 'complexity' of the sound (I don't know how else to explain it)--it sounds kind of like clockwork only amplified and less regular...sometimes twice, sometimes once per crank revolution (and sometimes not at all).

I've oiled the pedal spindles--these were older used spd's--but haven't regreased bearings.

I thought about the tight link theory, but the fact that I can't replicate the sound in the stand seems to nix this one. Sill, something to check.

I haven't found any play in the cranks at all. If the bb cups were pitted enough to make a sound, would this necessarily be accompanied by lateral play?

stausty

In my experience, no.

Ex Pres 

My first thought. Requires a limit screw adjustment.

Grand Bois

I think it's most likely the saddle. A crank arm that hits the FD will still hit it when out of the saddle and there will be a telltale groove in the arm. Pitted cups and cones don't clunk, in my experience.