Derailleur Suicide

[3WHELZ]

During last weekend’s ride, I experienced a significant chain jam while riding my Silvio 1.0. The chain had dropped off of the smallest cog of the cassette and jammed against the frame. While attempting to clear the jam, I damaged the rear derailleur hanger. I tried using my Park alignment tool to straighten and realign the hanger, but it snapped during the process. Unfortunately, quoting Robert, “this is the rarest of the rarest hangers, since only a few were made to accommodate a Campy triple set-up. After a considerable amount of searching, Robert was able to locate one, and sent it right away.

Yesterday, I installed the new hanger and checked it for proper alignment. I had the bike on a rack to also test the derailleur for any issues. Everything seemed to shift correctly. Today was to be a short 12-mile test ride to verify that all components were working properly. It began with quick loop around the neighborhood – no issues. Then about a half mile into the ride, the rear Campy derailleur committed suicide destroying the chain and bending a brand-new hanger that Robert sent. I have been riding a bike for over 50 years, and I have never experienced this! The cage fully separated from the body. I thought I would post some pics. Fortunately, I came to a stop before the cage fully lodged into the front wheel. However, I did have to carry the bike back home, since the front wheel became immobilized after walking it a couple feet.

I am hoping I can salvage the new hanger. Any opinions on whether to heat the aluminum before attempting to realign it?

Thanks, Dean

 

[trapdoor2]

Steel is very forgiving to bend with heat. Aluminum is not.

To 'get it right' with aluminum, you need to know the specific alloy in order to 'anneal' it (make it softer). Trouble is, once you anneal it, you need some special equipment to re-harden it or bring it back to a specific temper.

Best to replace it. I know, it might be the last one on the planet... If it were mine, I would try to re-bend it cold (coin toss if it works or not, unfortunately).

Do you know if these are Cruzbike specific? If there are none to be had, maybe you can get the engineering drawing and have one (or several) made?

 

[3WHELZ]

I believe that Doug specially crafted them back in the day. There were only a small number of us that order the frame with the Campy components.

Sourcing a replacement derailleur will likely be as difficult, since it is considered "vintage." If this indeed is the last hanger of this type on the planet, it may be time to try something new.

 

[Doug Burton]

I had to modify some but the modifications were mostly to accommodate some voodoo required for very short people (I'm on the border of that category) to be able to fit the Silvio 1.0. With the adjustable top tube adjusted very short, the chain used to drag on the dropout and try to lock up. I had to put a 2.5mm axle spacer in there to get clearance. This required me to have to mill 2.5 mm off of the hanger face to get the derailleur back where it needed to be. If you have a 39 inch or shorter x-seam, this might be the root of your problems.

I probably have a couple of these in the parts bin; I'll have a look. (Pardon me if my response isn't immediate. If I weren't already crazy, work would be driving there now. And it's not a very long drive...)

My S1.0 uses the Campy Comp Triple setup. I agree, I don't think I've ever seen a quality derailleur come apart quite like that. Might want to check your high gear limit screw; I remember having to use a longer limit screw from another derailleur to get the limit right on the Campy rear derailleur (don't quite remember why; it was a long time ago.)

Best,

Doug

 

[tiltmaniac]

3d printing metal is a thing these days.

If you can get a 3d scan or model, then you can get it produced at moderate cost indefinitely on demand basically forever.

 

[3WHELZ]

Hi Doug,

Interesting, the 2.5mm spacer you sent me years ago was necessary to provide the needed clearance to prevent the chain drag when using the smallest cog. The added width does make installing the wheel more challenging.

My x-seam is a little over 47 inches, so perhaps I have had the boom improperly setup from the start? I am 6'2". If you have any spare hangers, I would gladly reimburse you for them. Please PM me at your convenience, if you are successful in locating any spares.

After further examination, it appears that the three rivets that mount the cage to the body failed. In addition to the bent derailleur hanger, two chain links are bent in opposite directions. I guess that I finally overstressed the unit, which cause a catastrophic chain reaction. I believe that I have found a source for the derailleur, a shop on the west coast. I will confirm tomorrow.

Thank you, Dean

 

[hurri47]

Two years ago I destroyed the hanger on my v1.0 Campy Silvio. Robert still had a few hangers then, so I ordered two of them - one is installed, the other is untouched. Since it is made of unobtainium, I'm not willing to sell it, but on the off chance Doug has misplaced the recipe I could loan mine out for a scan so more could be made.

-Dan

 

[3WHELZ]

Dan,

I greatly appreciate the offer! I am going to attempt to realign the hanger this evening -- fingers crossed. If Doug is unsuccessful at finding one, I will beg Robert for forgiveness and see if he can work another miracle. I do have two of the "normal" hangers that I have never used, which were intended for a Shimano set-up. As Doug referenced, he had to work some engineering voodoo magic to make the Campy 10sp properly clear the front fork.

After extensive searching, I did find a vendor, nonstop ciclismo, http://store.nonstopciclismo.com/default.asp that had a reasonable priced ($175) new rear derailleur available. Other vendors' priced the derailleur at nearly $400. Both a new derailleur and a chain are on the way.

In the meantime, I am debating whether to bring my WC out of mothballs. I though it would be a few years before I would solo ride a three-wheeled recumbent again.

Dean

 

[hurri47]

Speaking of scanning, if it can be done at all, it can probably be done with yours if you don't snap it in two. Just flatten the bent part in the model the scan generates.

-Dan

 

[3WHELZ]

After about 20 minutes of careful nudging it with alignment tool, I was able to straighten it. I have not noticed and stress fractures.

 

[super slim]

Its good to see using a alignment tool so the hanger will be aligned vertically AND Horizontally!!!!

 

[3WHELZ]

The new derailleur and chain arrived last evening. For some reason, I cannot seem to dial-in the new derailleur. The shift pull and drop ratios seem to be somewhat off. There seems to be no sweet-spot when attempting align all cogs. I have triple checked the hanger's alignment both vertically and horizontally, and it seem to be dead on. Other than the cassette possibly being loose, it is unclear what could be causing this problem. If I cannot sort it out by tomorrow, I may be time to see if the LBS mechanic can sort it out. If anyone has any ideas, I will gladly take them.

Thanks

 

[3WHELZ]

The LBS mechanic solved the problem. I was concerned that the shifter mechanism was failing. Instead, the derailleur cable would not properly seat into the shifting mechanism. This was not a problem during previous use. Fortunately, the LBS stocks Campy cables. After some precision level tuning by the mechanic, shifting is smooth once again. Let the riding begin!

 

[elg]

Condolences on the chain drop. I wrote this post years ago http://cruzbike.com/forum/threads/why-does-my-chain-keep-falling-off.2574/#post-102574 about the problem I had with my chain falling off of my Sofrider. It never got fixed.

I haven't ridden my Cruzbike in several years, partly because of the chain issue and partly because of other reasons why it wasn't a suitable commute bike for the hills and downtown streets of Seattle. Occasionally I check the website to see what Cruzbike is up to. I note that after all this time they still don't appear to have a belt-drive bike. It's hard to tell from the photos, but it looks as though some of the new frames have the front chainstay fork mounted coaxially with the front axle. If so then the distance between the crank and wheel gears should be fixed, which would allow for a belt drive. I would dearly like to have a belt drive, to lighten up the front triangle and avoid frightening people with the oily toothed gears of the front sprockets as explained here http://cruzbike.com/forum/threads/new-owners-impressions-after-three-weeks.2582/#post-102582

Frequent chain drop was the most serious problem (almost got me killed on the corner of Stewart & Westlake one time), but front wheel slipping on steep hills was another issue. I've always thought that the Cruzbike would be perfect for an electric assist on the otherwise largely unused rear wheel. Electrics are so common now that one of Seattle's three dock-free shared bike services, LimeBike, now offers rental bikes with assist. I will certainly grant that a Cruzbike with belt drive and electric assist would be an expensive proposition, but the most costly bike is still surely the one that never gets used, no?