Repairing Vuma Quad

[monchito]

Hi everybody. I own a 180mm Vuma Quad for around three years and i´m a little bit dissapointed and not surprised that zipp stop making them, nor do I totally believe the explanations they give us about: (Please note Zipp has discontinued this item to focus on our core product lines of wheels, bars, stems and seatposts) .

Anyways, i still think that they are light, stiff and beautiful. My complain is that they are no resistant enough. The first problem was with a chainring thread; it dies and i had to made a bigger hole to put a regular chainring bolt. Anyways, not a big deal.

But some months ago, i feel some play in BB. At first i think that the bearings had some kind of movement in the BB, but when i dismounted it i find that was the aluminium axel that had looseness with the carbon rod. It already was a big deal .

And here i show the proces i did to repair it:

The first thing I had to do was a tool to remove the left crank nut...


DSC02992 por monchito3000, en Flickr

... and a tool to separate the axel from de crank.


DSC02990 por monchito3000, en Flickr

Here are some weights:


DSC02984 por monchito3000, en Flickr

I thought in lightening the axis, but finally it seems to me a litle bit dangerous.


DSC02986 por monchito3000, en Flickr

then I needed a device to glue the rods perfectly aligned.


utillaje por monchito3000, en Flickr

and a centered substitutes for pedal axles.


centrajes biela por monchito3000, en Flickr

before glue the cranks I realized that the left crank nut would not tighten against carbon fiber, so I had to fill it with epoxy putty. This particular case is inexcusable and I think it's because of a poor design. The nut should not have been just a embellisher.


DSC02994 por monchito3000, en Flickr

and finally i could glue the cranks:


DSC03139 por monchito3000, en Flickr


DSC03140 por monchito3000, en Flickr


DSC03114 por monchito3000, en Flickr

as glue i used a mix of epoxy and these little pieces of carbon fiber


DSC03095 por monchito3000, en Flickr

And here the cranks completed.


vuma quad repaired por monchito3000, en Flickr

I hope to use the cranks for a few years more. May be i´m too naïf, but I think a +1000€ cranks should not have given me any problem, at less, not so soon. Anyways, it still seems a happy ending.

[Stolichnaya]

Way cool. Impressive stuff, Monchito.
Please be sure to revisit this post to give an update on how they run when reinstalled and in use.
Those cranks are beautiful and unfortunately proprietary. Good on you for giving them a new lease on life.

[BobSantini]

Nice job
That workshop looks like the foundries of Mordor.

[Lig]

Hi Monchito,

Thats looks like a job very well done - but you will have to see if they hold up!!

I have the exact same problem (as i am sure do many). So I bought a new crank and have my old Vuma sitting in my shed as i dont know what to do with it!! If your process works I could pay you to fix mine

Good luck,
Lig.

[Brandonnie]

Beautiful.

[artray]

Brilliant

[madonna]

Bingo !!!!!!

You just shamed ZIPP.

[timsterc]

Brilliant !!!

[Mattias Hellöre]

That´s right approach to do things.
If the manufacturer stops producing things.Ask yourself why? A big fail in business math to stop selling something that is paid for.

The second problem here and many many cranks have is the corrosion, in the end the bond don´t hold up. Sometimes it´s just a lemon.

My experience is not only theorethical, I have broken Storcks, Lightning and so on here in my shop.

[SWijland]

Sweet work mate!

[monchito]

Nice job
That workshop looks like the foundries of Mordor.

Ja,ja,ja

You are right. Here i am working:


smigol por monchito3000, en Flickr

[monchito]

Thanks to everybody

At moment i didn´t too many Kms. You know, winter and so... But with around 300 Kms did not appear any problem. Anyways, i want to wait to climb some ports with suffering and misery before claim victory. Then i´ll be glad to repair yours.

I'll keep you informed.

[monchito]

Yesterday i did some kmts and, oh no¡¡¡, i felt the looseness again. It´s very small, and not always there, but it is anyway.

!!!!For the eternal eye of Sauron¡¡¡¡

So i have to disassemble and see if it´s the side i already repaired or if it´s the other side, and i don´t know which could be worst.

i´m beginning to hate Vuma´s.

[monchito]

Hi, finally i repaired (again) the Vuma Quad´s axle. This time i did three little slots, 16 little holes and a kind of battlement on the top. I just used epoxy without carbon dust this time, and i cured it at least for 6 hours at 60ºC after 16 hours at 23ºC.

Here are the pictures:


Eje 2º intent por monchito3000, en Flickr



Eje 2º intent (2) por monchito3000, en Flickr

Past time i didn´t care about temperature or cure times and just scratched the aluminium with too much faith in epoxy´s adhesive power.
I really hope not have to repair it again.

[mnmasotto]

You are superman!!!