Vitus Nucleus 26 mech hanger

Hi all, eldest has a nucleus 26. We have gone through 6 mech hangers in the last 6 months, with 3 in the last 3 weeks. The 5th one went, and mech went into the wheel and twisted chain so have replaced whole drive train. He has just put new deore mech into back wheel.

Is this a case of ‘they all do that sir’?

Indexing, chain length, chainline all fine. When I replaced the drive train I went from the heavy action/heavy spring box 8 mech/chain/cassette to deore 10 speed thinking the finer tolerances and easier action might take some load off the hanger. I have also used CNC hangers rather than forged ones for the last 3 replacements.

Where next?!

I came in here to suggest a CNC hanger after daughter bent her OEM rather easily at the weekend. Rather worrying that you’ve found those no better! I think the flaw is the mounting hole in the thin section. Makes a very weak spot. I’ve got a pilo replacement to fit, really hope it lasts! There are cheap (£5) eBay options. If it ends up breaking loads I’d be tempted just to buy cheap ones.

How about a cage around the mech?

It’s very clearly flawed – I think I’m going to get onto wiggle as well…

They seem to be breaking under normal loads – not sure a cage will help

I think ours was damaged by a fall on that side. A cage would help in that instance. I have to do as trail side repair and was very surprised how easy it read to bend back. I wonder if there is scope for someone like betd to make a thicker version it one that does not use a counter sunk bolt head. It looks like this design has been used in a number of different brands models over the years. May be worth a search to see if it was an issue for any of those and if there were any solutions.

Have you got a link to where I can buy a spare please?

CNC
https://gearmechhanger.com/epages/950018694.mobile/en_GB/?ObjectPath=/Shops/950018694/Products/D189&ViewAction=ViewProduct £25

OEM
https://www.chainreactioncycles.com/p/vitus-hanger-14-nucleus-24-and-26-2019 £15

eBay search for Vitus nucleus 26. £5-6

Is the freehub jammed, that could be the cause of it?

I’ve today fitted the pilo replacement from the link above. The hanger itself was straight out of the packet (checked against a straight edge) however on the bike the mech was running very close to the cassette, so close that the down shift from 4-5 (or maybe 5-6) grazed the back of the mech body with the chain. Putting my park hanger tool on it showed poor alignment. Given I checked the hanger before installing this error must be in the frame. Quite annoying having to bend a brand new item to fit!

Ah – good shout, to check frame alignment. I’ll see if I can borrow a tool and see where we’re at… I had an affirming 30 mins on web chat with CRC – “try a CNC hanger” and “not a known issue” and “no we won’t replace the hanger under warranty” and “if you want to return the bike, fill out this form”. Bit nervous about the last one as there’s a lot of unpicking with upgraded parts now…

Sounds like the frame is out of alignment.

+1 Pilo hangers. Ran them on two previous bikes and I can swear they improve the shifting ever so slightly.

Either that or the paint surface is a bit thick. My money is on the dropout itself not being correctly aligned. I don’t have any issues fitted the wheel so I don’t think it can be that bad. Its working now but I will probably take another look and may even face the frame where the hanger mounts.

Ok – so using a pretty hefty park tool, the alignment seems to be about 15mm out at the wheel, with new hanger fitted. Is this within normal tolerances? Explains why indexing has always been a headache. I have ‘adjusted’ brand new hanger so that we’re aligned, which of course weakens it. Fitment seems poor. 

15mm out with a new hanger is quite a lot. Definitely sounds like dropout / frame misalignment.

Might be worth taking the frame to a decent mechanic and getting them to take a look. Pretty sure Park Tool do frame alignment gauges which are prohibitively expensive for a home mechanic, but a decent LBS should have.

I didn’t measure mine but the gap was bigger than I expected!

Update time… wiggle sent courier to collect bike on the 25th July with a commitment to a 2 week turnaround – Yay. It’s school summer hols and I overlooked that eldest might want to ride his bike a lot – Boo.
Chased wiggle on Friday as not heard anything and got an email today saying the bike never made it to their warehouse – Boo.
And that it will be 2 weeks from when they receive the bike to a resolution – Boo.
And we’ve a holiday planned with loads of riding starting next week – Boo.

If the bike hasn’t arrived with them yet I’d place money on it never getting there.

Yikes, one of these on the way! Will get an ebay hanger anyway, hope ours has good alignment!

The original hangers seem very weak. One of the fixing bolts passes through the thinnest part of the hangar, further weakening it. We have experienced constant misalignment of the hangar in the year that we’ve owned the bike. The shifting always need sorting and usually the hangar is slightly bent out of alignment.

I bought a couple of the eBay hangers and put one in my lad’s biking bag as a spare. This proved to be a wise decision as at about 2,300 m on alpine hillside the hanger finally snapped. We were able to swap it and get going in about five minutes, which was a relief.

It’s just crap that an otherwise ok bike is let down so badly by such a simple/obvious oversight. Your experience is identical to ours @troutwrestler. With a hanger alignment tool and new hanger fitted you should be able to see if your frame is straight – great advice from @nixie further up this thread.