Lotus Elan

Broken shock to front roll bar stud

PostPost by: rgh0 » Tue Apr 18, 2017 1:25 pm

I was checking out my Elan over Easter before the following weekend where I am going to the Australia Lotus Clubs national meeting and track day. Discovered that the stud had broken off the bottom of the RH front shock. That will teach me to check the car the weekend before a meeting rather than the weekend after :oops: Running a bigger diameter roll bar (22mm in my case) make this failure more likely

No real chance to get a new shock out of the UK before the next Friday given the Easter Monday holidays. i had a pair of old front shocks but did not want to use them as the spring platforms were not adjustable and the springs rates less than I wanted to use. So I decided to make up a new stud and reweld it to the shock bottom eye.

I used a suitable forged high tensile bolt and machined it to the correct profile and cut a thread for the new smaller diameter threaded section, handy to have a lathe when you need it for urgent jobs like this. I also made the stud a few mm longer as the standard TTR shock stud is a little short and you have to over compress the roll bar securing rubbers to get the nuts fitted on the threaded section fully. The stud had failed due to a fatigue crack around where the head of the stud thats welded to the shock had been machined with a sharp radius. Hopefully using the bolt with its forged head it will be less susceptible to this problem. Got a friend to weld it to the shock as it would take me a week of practice to do a top quality small fillet weld that's needed to secure the stud head to the shock eye.

It should be OK now and hopefully better than original but I will order some new shocks as the other one is probably due to fail soon and i have wanted an excuse to experiment with some different spring rates :D . The current TTR shocks and springs have lasted more than 10 years of regular racing so I cant really complain.

cheers
Rohan
User avatar
rgh0
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 7491
Joined: 22 Sep 2003
Location: Melbourne, Australia

PostPost by: patrics » Tue Apr 18, 2017 7:31 pm

Hi Rohan,
I'm interested to know how well the roll bar fits? Late last year I set my suspension and was really pleased how well the roll bar fitted - bolted to chassis mounts and offered the ends up to the shocks and it fitted absolutely perfectly - normally I'm thoroughly pissed off that nothing fits and the roll bar is one thing I expected to be slightly out and so causing a side load on the shock.
How good was it?

Regards
Steve
patrics
Fourth Gear
Fourth Gear
 
Posts: 539
Joined: 21 Sep 2003

Total Online:

Users browsing this forum: No registered users and 16 guests