Sonder Cortex build questions

For the cables you can use this (also cheaper non-branded versions on eBay/Amazon):

https://www.bikeparts.co.uk/products/jagwire-internal-housing-damper-4-5mm-grey-1-5m?currency=GBP&variant=45336236261533&utm_source=google&utm_medium=cpc&utm_campaign=Google%20Shopping&stkn=a894e8283159&gad_source=1&gclid=EAIaIQobChMI6o_-2-n8igMVh4pQBh319DZyEAQYAyABEgIg7fD_BwE

For the headset I'm pretty sure you're right, should just be drop-in bearings and a top cover/crown race to cover them and the 'cups' are part of the frame but would need to see some pics of the headtube really to be 100%.

Sure my bearings dropped straight in when i did the same thing. I'm running some thin foam tube over the cables internally, you have the little hatch on the bottom bracket for the cables? think it has three holes from memory so work out all cable housing lengths in advance, slide the tubes over then thread the end through the hatch/plate. Watch the little hex, rounds easy!

Cheers for the tips guys. The frame arrives on Monday so will have a look. I have now ordered a Brand X drop headset as from experience they are very good.

Will buy those foam housing things. Routing is going to be my main challenge as I ride continental (RH rear brake) and the frame only has one entry on the left...

Also a bit nervous about dropper. I want to use my Trans X 170-200 adjustable dropper and I insist on slamming but not sure it will all fit in the frame.

I keep looking at these for the mini a11ys. Only thing stopping me is it'd be a step up in wheelsize for them, so the bargain £350 frame/shock snowballs into needing forks and wheels too...

Routing is going to be my main challenge as I ride continental (RH rear brake) and the frame only has one entry on the left…

I found one of the cheapo Amazon internal cable-routing gizmos useful, though if the routing's like my Transmitter, it's relatively straightforward to feed the cables in through the upper ports then out of the large lower one. More difficult the other way round. Transmitter headset bearings are integrated and sit direct in the frame, no cups. I suspect the Cortex will be the same.

Cheers. Thee question is which cable do I choose to go through the single hole on the left: brake hose or gear cable? I run continental so both controls are on the right but I can only crossover one, the other one will have to stay on the same side where there are 2 holes. Will look terrible and also exposed to snagging a bit so perhaps do the gears but will the tight loop affect shifting? They should have had 2 holes on each side really but I guess it's a UK focused brand.

^ probably answering my own question ?.

I was thinking I could try SRAM GX AXS mech and shifter at around £300 to resolve this neatly. The rest of my groupset is XT 12 speed though. Compatibility?

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I started the build today.

Ran all the cables and hoses.

Stripped the 23 Big Al, the donour bike.

Couldn't insert the dropper which fits nicely without a cable but the outer snags onto something in the seat tube that chews the coating of the outer. Went through 3 outer cables with the same result despite "trying everything". I even bought some small round files to file any burrs that have been left after the hole was drilled (which I am pretty is the problem), but to no avail. There is a bend so I can't see from the top even with a torch light.

I contacted Sonder who sounded friendly but haven't come up with a solution.

Any ideas?

I know it was cheap at £350 but it's actually quite expensive as useless.

I seemingly bought the last one so not sure what's gonna happen. I bought bits for it, applied frame protection etc.. plus headset and new forks.

Tough situation. Hopefully they will do the right thing, whatever that is.

A bit pissed off by the absence of QC so apologies for the rant.

I bought one of these too. After seeing your message, I grabbed some outer and it threaded through with no issues.

Sounds like something is not quite right with yours.

^ Thank you. I can do that too but when inserting the dropper the outer snags as its trajectory is determined by the fact it's attached to the dropper as oppose to being able to go around any "obstacle".

Sonder are not being very customer centric so far. I have stripped my bike so not having a frame at all is not an option. They don't have any L anymore so I don't know what they would do if there was a warranty claim. Really disappointed and not sure what is going to happen.

Am I being unreasonable in asking for a replacement frame that is not defective?

I'd use one of these cables.

https://jagwire.com/products/diy-cable-kits/pro-dropper-kit

They're a smaller diameter and more flexible so should fit through the hole better.

I'd also enlarge the hole a little by running some stainless steel braided hose I have through it or with a small grinding wheel in a dremel*

I can't see there being any inner guide tube in the frame there. It'll just be a hole drilled at an angle with a strengthening plate round it.

*you may not want to do this.

Thanks Stu. That might help although I have spent so much time on this and dealing with Sonder CS who do not understand the detriment caused that I am kind of giving up for a simpler life. Problem with Companies with a good CS reputation is that when they are in the wrong, it comes as a surprise to them and they're often not used to react properly and do the right thing by the customer, for all their ethical posturing. Not sure what to do next.

Not sure what to do next.

If it was me I'd do what I said above. 😉

I had a very similar problem on a custom steel frame.

Except that had a curved guide tube welded in that was a little more tricky to fix.

The problem is that this is what happens to every outer despite the utmost care. It literally chews the outer. I am pissed off enough like that without spending yet another £20 for potentially nothing. It's a clear warranty claim that Sonder is refusing to honour.

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It’s a clear warranty claim that Sonder is refusing to honour.

Sounds familiar.

I bough a fork off the Alpkit ebay store.

Said fork developed a problem.

I contacted them and they said no warranty as it was sold on Ebay.

Took the fork to a Rockshox dealer who sent it back to Sram with just a screenshot of the sale as proof of purchase.

Sram warrantied it and sent me a new fork.

Make of that what you will.

Yes absurd. Selling on eBay doesn't change anything to consumer's rights.

Few thoughts

These were cheap clearance frames, the most I would expect is a refund, not a replacement

There can't be *that* much down there to cause this issue. What's the dropper and how far are you inserting it before this happens?

Are you really really careful with the cable coming out as you insert the post to make sure there is a small loop inside the frame and it's not rubbing on the frame exit hole?

I still think it wouldn't take a lot to get that sorted. (warranty or not)

If you're anywhere near the tweed valley I'll take a look at it for you.

Have you had anyone else look at it or try? Or a bike shop perhaps? Different set of eyes or different technique might work.

Also, in the installed state does the scuffed outer appear external to the frame or is it hidden inside? If inside just crack on, it won't affect performance. Or if external maybe just add some heat shrink round it. It's not a massive problem.

I just fitted a Brand X 200mm with no issues:

Try smearing cable in plumbers silicone before threading through. Might help it not snag.

Thanks guys. I tried all of that. The post is the Trans X 170-200 so a brand X but adjustable. It only goes in 4 inches before the snag happens.

I am quite experienced and a good and very experienced bike builder friend of mine tried. Probably 6 hours combined of trying (no exaggeration there). I don't trust LBS sadly, they will probably do more damage than good.

A simple refund would have done if I had spotted it out of the box and put it back in. But there is customer detriment here. Loads of work, my Ragley in bits, buying some needle files, buying new forks with the right travel, frame protection has been applied. I know they don't give a shit.

The price I paid is utterly irrelevant. If they had advertised it as faulty I wouldn't have bought it.

It's not my fault if the QC failed and they can claim from TW.

If it had been a private sale, fair enough but this is a reputable supplier with a good reputation for ethical behaviour.

If they don't have any other frames what would you like them to do to resolve? Are they not willing to refund? The extra bits aren't really their cost to cover sadly.

I think it's a warranty claim. If they choose to not stock frames for warranty purposes then why not send me a 2024 frame which must have cost them roughly the same, which is around 250usd EXW at the most.

It's no different to the frame cracking in 3 months time. What are they going to do then? The eBay ad says it's new and doesn't say there is no warranty, probably because it can't not have a warranty.

they are selling off the previous models at deep discounts, they don't come supplied with a moon on a stick

If they choose to not stock frames for warranty purposes then why not send me a 2024 frame which must have cost them roughly the same, which is around 250usd EXW at the most.

Lol, they do not owe you a new current version frame.

They are not 'losing' what it costs them to buy. By providing a current stock 2024 frame they would be 'losing' what they can sell the current stock for.

It’s no different to the frame cracking in 3 months time

It's very different. But also, if your frame did crack in 3 months time then refund is also an option at that time.

It feels like you may be expecting a bit much here if you're going at them for a replacement current frame.

Looking down the seat tube surely you can virtually see the exit hole looking at the pics? Have you tried shining a torch down but also back through the hole, and vice versa, look through the exit hole whilst shining a light down the seat tube?

Try putting a ball of blu tac or something a bit smaller than the seat tube diameter on the end of some cable outer and see how far down it goes. Does it snag on anything before the seat exit hole?

Do you know of anyone with an inspection camera?

Based on where the cable is getting damaged below the bottom of the seatpost, where on the frame do you suspect the outer damage is occurring?  It would appear there’s nothing on the down tube to catch on other than the exit port.

I fitted the outer and inner plus connected the lever to make sure everything was tight before I inserted the post. The post went in fine and just needed a bit of push/pulling on the cable to get it through the frame.

I’m guessing you did the same?

It was actually one of these easier dropper installations I’ve done.

There didn’t appear to be any obstructions. Just an aluminium tube and a hole at an angle.

On my first sonder signal ti frame I had a similar issue. Must have been some sharp edge on the inside of the seattube or downtube hole (don't recall which). It didn't prevent it from getting through but shaved the outer when feeding it through. Wasn't an issue once installed but not ideal. I got a warranty replacement frame (for a different issue) which was fine.

Try removing the lower pivot so you can get access to the back of the hole to tidy it up.

A simple refund would have done if I had spotted it out of the box and put it back in. But there is customer detriment here. Loads of work, my Ragley in bits, buying some needle files, buying new forks with the right travel, frame protection has been applied. I know they don’t give a shit.

It’s frustrating but none of that is really their problem, aside from issuing you a full refund the rest is just life.

Are you gently pulling the cable out the frame entry hole as you push the dropper down into the seat tube?

they are selling off the previous models at deep discounts, they don’t come supplied with a moon on a stick

No one ever said that. The discount is utterly irrelevant. My frame is faulty. It's very easy to make fun but you're not the one with an entire bike ready to go in and because of a QC issue I am stuck at stage one or 2 of the build.

Thanks for all the suggestions. Believe me they've all been tried. The killer here is the bend.

Given the amount of grief I would expect a business that claims to be ethical to do the right thing. They might not have to (I don't see it any differently to a warrant claim personally) but I think they should. I actually prefer the old frame as the new colours don't appeal. I appreciate there is potentially a loss of margin for them, it's the cost of doing business. In that case they should have kept the old frames then and not put them on eBay. There is no difference between my warranty issue and a breakage in 3 months time for which they will have to supply a new version frame. Or should they decline the claim because it's costing them a sale?

The cost or the sales channel is utterly irrelevant.

Anyway another friend of mine has offered to give it a go. The outer doesn't just get scratched superficially (I always expect that), they get chewed up and gouged however careful we are, resulting in every attempt to end up unsuccessful at the lever. I have now gone through 6 outers.

What problem do you think the chewed up coating will cause you? You won't see it inside the seat tube.

The cost or the sales channel is utterly irrelevant.

I suppose many are thinking it is relevant, but ultimately that's between you and Sonder.  People will always see a cheap closeout deal in different ways and personally I would expect a level of compromise if I'm paying significant less than the RRP.

There's little detail in how much conversation you've had with Sonder to allow any of us to have an informed opinion of their handling of this situation, just your level of frustration.  The thread would imply you only raised an issue with them on Monday, it's quite possible the problem you have has not been experienced before and they have no knowledge of your mechanical capabilities or otherwise. 1-2 days whilst annoying is not hugely problematic in my opinion.  It's just a bike frame.

At £350 including shock and next day delivery, there's little in it for Sonder to offer extensive customer support on the sale ... making the cost very relevant.  I certainly wouldn't be looking for a warranty swap out for a later model on what is a customer acceptance point.  I think the sales channel is also very relevant making a refund the best/only you should expect on an ebay closeout deal.

If what you want is a refund, use the power of the sales channel and send them a message via ebay explaining why you feel the frame isn't fit for purpose with photos.  Tell them you'll raise a claim if they don't offer it.

If not, use the £850 you've saved on the RRP over a new frame and buy a wireless dropper.

Or just accept it's not quite the bargain you thought it was and find a way to live with it.

You have the power to resolve it, just be realistic in the boundaries that Sonder will work in to find that resolution base on what you paid.

As a couple thoughts

If the issue is inside the seat tube then have you tried putting the foam damping outer over the point where it will catch, protecting the outer.  Or even just wrap that area in insulation tape?  Obviously all done before you fit the dropper.

If it's at the exit port then how about a thin screwdriver, a few old cable inners wound together or a couple of cable ties pushed up into the hole between the port and the outer to try to protect it from whatever is causing it to catch.

Sl2000, the issue is the dropper itself won't go in because of the snagging, I am not too precious about the condition of the outer itself.

Dave_h. Thank you, some good points, which I all considered. You can raise doubts all you want, that's fair. I can be frustrated AND the mostly innocent party here, the two are not mutually exclusive. We will have to agree to disagree on the relevance of the sales channel and price here.

On a more positive note, I will try to wrap and super glue some thin emery cloth to an  outer to run it up and down. Just thought of it last night.

I don’t think you mentioned that the dropper itself won’t go in, it read as if it was just the cable snagging when you do.

You mentioned it happens once you push it in four inches, if that’s the case you would be able to see what’s causing it surely?

Based on your numerous attempts, how far in (from the bottom hole) do you estimate that the cable outer is getting snagged?

And IME it takes a hellva pull to damage an outer like that - if you're not happy then just send it back and get your money back.

I’m still struggling to understand where this issue is. As above, can you shine a torch down and see the issue?

Assuming it is a burr on the bend where the cable feed at the bottom of the seat tube, can you use some old inners and use them and pull them forward and back to in effect file/rib/friction down the sharp point? Can only be aluminium so should be soft?

As above, not sure what else Sonder can do. They’ve replied within 24 hours, a refund on your cost is fair. The rest is very unfortunate for you and you have my sympathy but it’s not their issue. I’d just insert it, make sure it’s working (which I suspect it will fine) and enjoy the frame

It looks like the curve on the seat-tube is going to make the angle the cable exits the tube very, erm, 'snaggy', if you try to push it through from above, which it sounds as if you're doing.

Can you not, if you haven't already, feed it through from below then connect to the seatpost before very carefully manipulating the cable to minimise catching on the exit port as it feeds through. Presumably that's what's causing the outer damage? Sounds also like the more flexible, thinner cable suggested by @singlespeedstu above might help.

Or finding a way of smoothing the inside upper edge of the port, though that looks fiddly.

I guess the other option is that something sharp is obstructing the tube, but that seems unlikely, it being a tube and all.

Any updates OP?

If the dropper won't go in are you saying the snag is near the top of the seat tube?

If so, you should be able to see whatever it is. Try ramming an old seat post down there to clear the snag.

LED Endoscope Borescope Inspection Camera 1.5M IP67 LED Lens For Android and PC https://amzn.eu/d/fcmKbfe

just this thread made my buy a small frame to build up a "spare" bike for the OH and try and convert her

I need closure on this, where is OP?

He's miniaturised himself and is inside the frame smoothing off the troublesome sharp edge.

@mick_r

https://amzn.eu/d/fcmKbfe/a >

Ohhh, I need one of those.

Bought.

Sorry guys. My trick of a make shift flexi file with emery cloth worked a treat. Quite a few bits came out. The point about the softness of aluminium was valid. That probably wouldn't have worked so easily with steel let alone Ti. It also left a right mess of paper etc but that all came out with gravity.

The build can be completed, will post pics.

Sonder have been very helpful and sympathetic. Had a good chat with the CS manager and they are still "learning about eBay".

There isn't such a thing as "sold as seen" when a brand sells new products direct as a business to consumers. Product liability, warranty and consumer rights remain intact in that case irrespective of price and distribution channel. That was my assumption and that got confirmed by a friend in compliance at an FMCG.

I can see why there would be more friction and less goodwill and perhaps more difficulty to enforce but in this instance Sonder were quite helpful anyway.

Super well done OP. Now you have a super bike for peanuts and can finish and enjoy it

Thanks SA. Yes total build should be around £1,200 as I still have a few bits from the CRC firesale. Aiming for 30lbs or so without pedals although perhaps a tad optimistic.

I assume say, 25% sag out of 120mm will lower the BB by 30mm compared to unsagged? Is it that simple? I also assume BB drop measurements are taken unsagged in the spec sheet?

Does that sag extend the reach at all ? If so by how much?

Thanks all.

I'll be building mine out of junk, i worked out i've got enough unpopular parts sat around that people don't want to buy, that it'll make an excellent bike for the OH/ the boy if he ever wants to ride a light bike

i've got a coil pike, that i'm not sure may be too firm.... superstar wheelset, old xt 11 speed drivetrain, oneup dropper which may be too long.. Sods law says it will come up lighter than my Top Fuel which has some fancy parts on it

re BB sag and reach, technically reach will shorten as the bike moves through its rear travel (i think)

Nicely done, @nickfrog.
Looking forward to seeing the completed build now.

Sonder have been very helpful and sympathetic

Matches my experience.

Enjoy your new bike OP. Interested to hear how it rides.

re BB sag and reach, technically reach will shorten as the bike moves through its rear travel (i think)

Well, if it was only the rear of the bike compressing: yes, the reach shortens as the rear moves though its travel... but the front suspensions is also moving through its travel, and reach lengthens as a fork compresses. So in general, on a full-suspension bike, reach shouldn't fluctuate nearly as much through travel as it does on a hardtail.

Enjoy your new bike OP. Interested to hear how it rides.

Thanks Nick. I will report back although I live on the South Downs and it's a right quagmire so not gonna happen for a while!

I don't think I am very lucky. The snagging is still present.

To minimise the risk of snagging, I ordered a 170mm dropper. While I was at it, I ordered a 31.6 as my longer one was 30.9 with a shim.

It doesn't go in. This happens (used a 31.6mm fixed post for illustration).

No amount of filing makes any difference.

No idea if related to the initial issue but I don't think so. It was just hidden by the smaller diameter. Video:

https://jmp.sh/s/jQ81Jag0LFPCfKl5K6BV

For those who got their frame recently, what did the box look like? Is it a "proper" Sonder branded box? Mine wasn't so trying to establish if it was a return or a "second" with a known issue, being the last one.

Weld blow-through at the seat tube/top tube joint maybe?

No the issue is lower than that at 18.5cm from the top of the seat collar. I *might* be able to see a dark spot in the seat tube now. Not sure at all, but it is very small yet much darker than the surrounding silver aluminium. It looks a bit like if a bit of liquid metal was splashed there and cooled down in situ, if that makes any sense. Will try and do more filing in the morning lol.

When I’m trying to save old steel frames which have stuck seat posts, once they’re out I usually get some dowel wood, cut across the top, slide in some sanding sheets or wet and dry and push it down the seat tube and spin it, clears it in no time

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What do you guys see?

I'll take the frame to the shop tomorrow for a 4th opinion.

Looks like quite a prominent lip. Can you see and feel it catching with a long thin tool of some sort?

My Large discount Cortex is probably going to struggle with my 170mm dropper.  I get 22cm post below the top of the seat tube before it won't go any further.   It looks like it's slightly above where the bend in the seat tube start but I assume it's related to that - externally about the point of the Union Jack decal.

How much seatpost can you get into your seat tube?

I'm taking the view that it's an XC frame that was designed when 170/200mm droppers were not common place - it's a pretty flat top tube compared to more modern designs.  If it's too tall then a shorter dropper still makes it a bargain bike.

Mine came in a Sonder box that's marked up "2 x Colibri" so obviously not the original Cortex box.

You can still play with the old Cortex bike builder on the Alpkit website, it lists a 170mm dropper as an optional upgrade.

At 5'10", I'm at the small end of a Large frame so not surprising that a 170mm dropper is too big.

Would a 30.9 dropper with a shim work? The thinking being that the shim won't reach as far down as the protrusion inside the seattube, but the narrower dropper might clear it and successfully be inserted deeper into the seattube?

Finished. I managed to transfer everything across from the old frame minus a headset and an inner cable which is a record, I think.

OP,  here. Sorry late update. I finally got round to finish this build. Sonder were very good in the end and found an excellent solution, which I probably can't make public 😂.

Anyway, surprisingly light at 28.5lbs (w/o pedals).

Select+ shock
Select+ Pike 140
Roval Controls
SLX + GX cassette
One Up V2.1 180mm
TRP Slate4 brakes
Wolfpack Cross 2.40 tyres 
TAG carbon bars and e*13 stem

[img] [/img][/url]

Bike proving to be good to ride if a little "passive". But after a few weeks the constant creaks have become unbearable and unfixable. I suspect they come from having to use the wrong size dropper near the bend as it doesn't allow a very long shim. 

So the only solution to that particular creak is a 125mm dropper, which is not gonna happen.

Cable noises and rattles are also difficult to reduce any further.

The frame has cost me around £70 in the end but even if it was free, it's not fit for purpose for me, a creak with every crank revolution is funny for a few miles and then not so much.

Will sell it and use the proceeds to go toward a proper product.

Sonder know exactly what's wrong with those frames, hence their excellent customer service in paying me off. Is it a way to run a business? 

Mate, just sell it and move on. I’ve never known so much drama over a bike frame before, life’s too short. 

I would thread the cable from below, working upwards. Smother the outer in thick grease to overcome any burr it's catching on. Thread the outer in just to the point it will eventually sit at (i.e. 30cm or so within the frame). Push a cable through from the handlebar end and attach to the new cable with tape, then pull back through. I had similar on my Specialized build, it was chewing the outer cable on an internal burr. When you push the dropper into the frame you will need to pull the cable down at the exit point on the seat tube at the same time i.e. push down on the dropper with one hand and pull the cable down and through the exit port with the other.

"I’ve never known so much drama over a bike frame before,"

No drama here, you've made that up.

Can I suggest you ignore this thread if you can't cope with it?

I have no issues with anyone being happy with a frame that rattles and creaks. Conversely, I can't so yes I will be selling it.

76 post thread about a cheap frame that makes a bit of noise and I’ve never had a full price bike that isn’t a little rattly. 

Can't help if there's creaks in the linkage, but when I built up my Cortex, I put the cables/hose through a Camelbak neoprene insulated hose cover thing that I had lying around. It's pretty much silent. I don't have any creaks from the linkages either, but mine is the earlier design with the pivot on the seat tube, not the top tube.

I also have a lip in the frame which means I can't push a seat post down as far as you might think - but I'm not the tallest so a 150mm dropper isn't an issue for me - a 150mm oneup would fit, but a brand-x wouldn't. The only creak that I do have is where the seat clamp on the oneup dropper is worn, which makes the seat creak when pedalling sat down... 

"76 post thread about a cheap frame that makes a bit of noise and I’ve never had a full price bike that isn’t a little rattly. "

Are you OK? You know you don't have to open the thread if you can't cope with its content. 

I never had a full price bike as I only build my own bikes so I can't really comment. I certainly never had to cope with a permanent loud creak in the seat tube (in addition to the rattles, that are not little). Sorry to hear about your issues on that front.