Lotus Seven S2 A Frame

[Addlightness93]

Hello! 
wondering if anyone knows of a company that makes a replacement rear A frame as mine needs replacement. Or if maybe I have to have one made/mine repaired. Thank you! 

[MV8]

Fabbed or repaired is likely your best bet unless you want to order from Caterham. What is wrong with the one you have?

[Addlightness93]

It ripped itself off the differential mount. I’m sure it can be fixed would just rather replace it 

[IamScotticus]

I think Redline Components is your best source.

https://redlinecomponents.co.uk/

I would call Chris Mintoft there.  

HOWEVER,

MV8s suggestion is good, to have one made.  It's a very simple piece to fab up, and could be made with additional strength.  The A frame one of the things I would agree isn't worth the expense of a factory made part.  These aren't Concours D'elegance cars. It won't ever be scrutinized for originality.

Do plan on continuing using the original soft rubber bushes, not the hard neoprene.

[Addlightness93]

That’s very helpful, thank you! And agreed I want something a little beefier. Would much prefer something like this doesn’t happen again!

[MV8]

There have different designs for the diff attachment. Some pics of the damage could be helpful. It's been discussed a few times. Has it been track use, run over something, new hard bushes that prevent the diff from rolling left and right over the bush?

 

 

Edited July 22, 2024 by MV8

[jbcollier]

Using an a-frame causes enormous loads to be transferred to the axle at places that were never designed for them.  The S1 system was much better (4 links and a panhard rod).   The problem with beefing things up is that you just move those excess forces elsewhere.

[MV8]

I agree that ignorant "beefing" can be a problem. Good engineering spreads the load. That is the point.

Everything bends or breaks with enough load. The arm should bend when overloaded, not break at the attachment, crack the diff case, or tweak the chassis. 

[Addlightness93]

I ended up going with a replacement A frame from redline components 

[SevenAmerica]

Sorry, just saw your post - I’ve a couple good used A frames available in case Redline doesn’t come through!

[jbcollier]

My rear a-frame is much patched and reinforced.  Good idea to go with a new one!

[pethier]

A-frame is a great way to lower rear roll center.

 

Agree that welding tabs on a pumpkin looked dodgy.

 

Caterham De Dion use of A-frame geometry looks better.  Suspension arms are longer as the De Dion tube is aft of the driveshafts.

Edited August 23, 2024 by pethier
typo fixes