Mounting a rack to ...
 

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[Closed] Mounting a rack to a carbon frame with no mounts

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Hi,

Planning a few road trips this year and need to carry my tent, sleeping bag, cooking equipment, clothes and food. All pretty lightweight kit.

I've just sold my touring bike prior to lockdown and was planning on buying another but prices are crazy so I've bodged together a solution for my carbon saracen avro road bike.

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I've taken a turbo trainer skewer for a 142 x 12 bolt through axle thats the same pitch thread as my skewer and got a friend to weld some extentions onto the rack so it reaches the axle. Then drilled the axle and tapped a thread into it.

I primed and painted it to make it all match.

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Not suggesting anyone else should try this but thought I'd post a thread about it in case anyone else is made enough to try it. I'll let you know if I die. I'll keep the original skewer in my bag just in case.

This is the axle through the frame and the bolts into the axle. Usual seatpost clamp adapter to secure the rack to the frame.

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Took it for a test ride yesterday to see if it worked. Seemed to hold up well.

[url= https://i.postimg.cc/wjMg1vvJ/20210403-125344.jp g" target="_blank">https://i.postimg.cc/wjMg1vvJ/20210403-125344.jp g"/> [/img][/url]


 
Posted : 04/04/2021 3:40 pm
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Show us all the pics.

You should start a sweepstake on how long
it will last before cracking the frame 😂

£1 in each between day 0 to never, could be quite a pot for the winner.


 
Posted : 04/04/2021 3:45 pm
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You should start a sweepstake on how long

it will last before cracking the frame 😂

Its a turbo trainer skewer designed to take some welly. I've personally not heard anyone crack a frame on a turbo zwifting going for koms.

But it's the commuter bike that's served me well for years, not the best one 🤪

Angle needs changing on the rack but I need to shorten the adapters first so they don't fowl on the tyre..

Tent will be in a seat pack so the panniers will just have sleeping bag, clothes etc, all lightweight kit.

Right side

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Left side

[url= https://i.postimg.cc/CM6zJWqj/20210404-160522.jp g" target="_blank">https://i.postimg.cc/CM6zJWqj/20210404-160522.jp g"/> [/img][/url]

The training skewer sits on metal inserts just like the original skewer did.


 
Posted : 04/04/2021 3:52 pm
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Thats not putting any significant extra force on the frame.


 
Posted : 04/04/2021 4:01 pm
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Thanks @tjagain. It's reassuring 😊

My worry is not the frame or my friends welding (he's a pro) it's the bolts into the skewer that will be the weak point but it's a beefy skewer. Time will tell.

Its also a good design for anyone wanting to proper fit mudguards to a bike (with some bodging)

But if there are any engineers out there that think this is a stupid idea, please educate me prior to my trip. Thanks in advance.


 
Posted : 04/04/2021 4:13 pm
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I like that, well jel.


 
Posted : 04/04/2021 4:16 pm
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Tubus make a rack that is supported by an extended QR and you can get a seat collar with rack mounting points. Fitted one to a friend’s bike for her to ride LEJOG


 
Posted : 04/04/2021 4:26 pm
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@doverbike do they do it for a 142x12 axle? I couldn't find anything which is why I made one.


 
Posted : 04/04/2021 4:33 pm
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Hard to say without knowing what size the screws are, but they're under shear stress, so probably ok. If they have the shank (un-threaded region) in the stressed region even better, also makes a difference what the material is, but I wouldn't be worried. Nice solution.
Just keep them tight so they can't bend.


 
Posted : 04/04/2021 5:46 pm
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@richmars they are full treaded bolts. They are pretty long, at least 2 or 3 cm into the skewer. Maybe 1 cm into nothing. I might see if I can pick up a bolt that doesn't have a full thread. Thanks


 
Posted : 04/04/2021 5:55 pm
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Speaking from experience, make sure the bolts are hi tensile!

Otherwise looks great.


 
Posted : 04/04/2021 6:05 pm
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You should start a sweepstake on how long it will last before cracking the frame?

Why should it crack the frame? The load from the rack is straight down to the rear wheel. It's a method used by Tailfin and they also sell axles including a "universal" one.


 
Posted : 04/04/2021 7:50 pm

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