Cycle Wings Keep Sheering On Sierra Based S7

[Matt brown]

I was looking for ideas on whether to re-make or strengthen the original cycle wings on my sierra based s7.

 

on 2 occasions now i have been out for a drive and my cycle wing mount has sheered at the front where it connects to the car, i have heard this is a common fault so not sure if it would be easier to reinforce the original mount or to start from scratch and re design and make new ones.

 

was wondering what other people have done in this situation and any pictures of peoples solutions would be great.

 

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[theduck]

Depending on what wheel offset you are running at the front it is possible to use the dummy struts from a 2b which have the wing brackets built in and are much more heavy duty.

[fry61]

The failure is due to all the vibration being concentrated at the point of fracture ( IMO ) All the cycle wings of Florin are mounted on s/steel flat strip -- 2 pieces of 25 x 3 silver soldered together. One piece is 25 x 3 throughout its length from hub to outside of wing -- the other is 25 x 3 at hub end & tapers in width, finishing at a blunt point just short of the wing. I believe this tapered design allows the flex & vibration to disappear before the fixed point at the hub. No failures with any bracket (yet -cross fingers) in the 5 years/ 50K miles & the wings are all mild steel trailer wings with a goodly coat of paint & under-seal so are not light-weight. Hope that helps.

 

A further point -- all wings are on 3 mounts each so less wobble than 2.

[Matt brown]

Florin have you got any pictures please.

[Jez Morton]

I had the same issue on my previous kit a Sierra S7. I ended up welding on some angle iron to the tube replace the ends that snapped, also I had to cut bend and weld the angle to achieve the same attachment.

[fry61]

Florin have you got any pictures please.

Out to-day -- Florin's MOT -- will do pics ASAP after.

[fry61]

 

 

Hope these pictures help, shout if more detail required.

[Matt brown]

Thanks I'll see how mine compares and get some metal on order I think

[fry61]

Shout if you need fixing details, Matt.