Author Topic: Suspension  (Read 164 times)

iambudge

  • Forum user
  • Posts: 5
  • Location: Bridgwater

Badges: (View All)
Suspension
« on: 08 Feb 22, 09:16 pm »
Right……. It starts, New engine sitting on the floor,  body style working that out to fit constraints of chassis, much coffee and garage time. Kinda have suspension worked out.  But I have a couple of questions I don’t seem to be able to find any answers to…. The first one being dampers on the springs, why doesn’t anyone seem to be using them?
Secondly, shaped bump rubbers to control roll, any reason why not? Or (as I’m yet to discover ) aren’t they needed.

Share on Facebook Share on Twitter


David F-R

  • Forum user
  • Posts: 171
  • Location: South Yorkshire

Badges: (View All)
Re: Suspension
« Reply #1 on: 08 Feb 22, 10:23 pm »
Interesting questions, no answers from me as a newbie. However, I'm looking at fitting 'Andre Hartford shock absorber' style, homemade, if only for appearances. Those, and a bit of rubber in case of bottoming out.

I'd be very interested in what experienced members say, and who's fitted what.
I'm not quite as green as I'm cabbage sounding.

RhysN

  • Forum user
  • Posts: 1093
  • Location: Tamworth

Badges: (View All)
CKGB Member
Re: Suspension
« Reply #2 on: 09 Feb 22, 07:33 am »
Hartford dampers... well I have made many sets and they are on many cars in other countries, just nobody here in the UK has picked up on them, so far. I still have several sets of the photo etched "labels" and done much working out the best friction material. I'm due to get more sets of the "lollipops" water jet cut. They do well what they need to.
Suspension, well there are a lot of different ideas on that, these things do not follow the "rules" that full size cars do for handling. In my early efforts in cyclekarts (15 years ago now) I tried to incorporate what I learned over 40 years playing with things such as Lotus, Formula Fords, saloon cars and such. In the same way that karting learned that car principles don't work I eventually learned something similar. I have been helped along that learning slope with my trips to the states. It has been hard for me to throw out all that background! I now have become even more fixed on my ideas of what make cyclekarts handle well or badly.
We must avoid torturing our brains with false problems, it occupies but it can annoy. In jest!

StefanN

  • Administrator
  • *****
  • Posts: 1052
  • Location: Bagshot, Surrey, United Kingdom
  • CKGB Committee: Yes

Badges: (View All)
CKGB Committee CKGB Member
Re: Suspension
« Reply #3 on: 09 Feb 22, 08:13 am »
I’ve got working Hartford style dampers on the Bugatti.   Some posts on my build journal:
http://www.cyclekartsgb.com/build-journals/bugatti-type-37-build/msg2426/#msg2426.

There’s a video of them working around Stretton circuit … but can’t find it at the moment.

Seven racer

  • Forum user
  • Posts: 152
  • Location: Worcestershire

Badges: (View All)
CKGB Member
Re: Suspension
« Reply #4 on: 09 Feb 22, 08:32 am »
I am starting with dummy Hartfords, and leaving the option to fit working ones later on, thus hopefully seeing what difference they make. They are part of the 'look'of the car, so I want to incorporate them in some form.
[ Guests cannot view attachments ]
Fitting mountings that are substantial enough to take working loads from the start, should see it being a relatively easy swap out once I have finished the rolling chassis.
I know it's double the work, but I'm trying to start from a base line of simple in order to be able to identify what works and what doesn't later on.
It will be interesting to see what effect, if any, they have, as there isn't much front spring travel at the moment. They will however, in my case, help with stability of the front axle, I hope :).

Peter

David F-R

  • Forum user
  • Posts: 171
  • Location: South Yorkshire

Badges: (View All)
Re: Suspension
« Reply #5 on: 09 Feb 22, 09:03 am »
Another really helpful photo Stefan, thank you.
Are the pressure stars made from spring steel or mild? (I'm rather hoping mild steel - easier to make.) Are you using wood friction pads?
Got my mind buzzing now.
I'm not quite as green as I'm cabbage sounding.

StefanN

  • Administrator
  • *****
  • Posts: 1052
  • Location: Bagshot, Surrey, United Kingdom
  • CKGB Committee: Yes

Badges: (View All)
CKGB Committee CKGB Member
Re: Suspension
« Reply #6 on: 09 Feb 22, 10:51 am »
The pressure spring stars are from one of the many Austin 7 suppliers and are made from spring steel.  The friction material is aluminium (I know, shock horror - excuse the pun).  Telfon is one of the best friction materials as there is minimal "stiction" and so a very linear response...but hey its a cyclekart.   Arms were cut from an old house alarm box.

Here's the video of the dampers in action

« Last Edit: 09 Feb 22, 11:10 am by StefanN »

dunworkin

  • Forum user
  • Posts: 91
  • Location: Bourne Lincs

Badges: (View All)
CKGB Member
Re: Suspension
« Reply #7 on: 09 Feb 22, 02:21 pm »
I had Hartford shocks on the front of my under sprung 1918 Buick roadster. I spent quite a lot of time and effort "tuning " them and found that getting the torque of the the big bolt through the middle was the key, inch pounds and not feet !

RhysN

  • Forum user
  • Posts: 1093
  • Location: Tamworth

Badges: (View All)
CKGB Member
Re: Suspension
« Reply #8 on: 09 Feb 22, 04:02 pm »
Sorry all, I had forgotten that Stefan had made his rather accurate versions.
Stefan, you call the link the "resilient Link" does it flex under compression?
Here are my labels. £4 per pair, post free.
« Last Edit: 09 Feb 22, 04:15 pm by RhysN »
We must avoid torturing our brains with false problems, it occupies but it can annoy. In jest!

StefanN

  • Administrator
  • *****
  • Posts: 1052
  • Location: Bagshot, Surrey, United Kingdom
  • CKGB Committee: Yes

Badges: (View All)
CKGB Committee CKGB Member
Re: Suspension
« Reply #9 on: 09 Feb 22, 04:57 pm »
Stefan, you call the link the "resilient Link" does it flex under compression?
They're called resilient links in the Bugatti spares catalogue I think and yes mine flex to take up changes in alignment.   Mine are 2 layers of leather bonded and then banded with thin steel.  A hole in each end of the leather has a steel tube, just longer than the thickness of the leather, pressed in with a washer either side.  The bolt then pinches down on the washers and tube.   Legend has it that originally something like elephant or rhino skin was used (eye roll).  I believe they're cow leather or polyurethane now.