still confused about a arms..

[Bonzo]

[quote=MarkB;68379]The Sierra based Roadster handles like a shopping trolley and understeers for a past time but that is my opinion and no doubt will be frowned upon[/QUOTE

That is only my personal opinion of that post

What a pity that you never took the time to build one & by your own admission, wouldn't even drive a 7 type car

Hey ho, you have to get your kicks somewhere & I guess this forum is as good a place as anywhere

[spud69]

Originally Posted by mark

If only someone could design a fabricated upright and revised wishbones so my roadster could go around corners, ive been trying to get out of my street for the last 18months but this damn understeer wont let me!

Is that why you only ever go straight on at roundabouts Mark....Wondered why that was....

Seems okay on front end grip here mind:

http://www.youtube.com/watch?v=4NdCl...&feature=feedu

[ayjay]

Danilo I dont normally get involved in these technical conversations because I dont know enough about it so its best to keep quiet-Better to keep your mouth shut and appear a fool than to open it and remove all doubt!
What I do know however is that your posts re roadster design come across as self indulgent to the point of arrogance. --Why doesn't everyone out there know as much as I do? ---These things should have been blindingly obvious to the roadster designer if only he had known as much as me!---
You may be pretty good on the cad thing but have a lot to learn otherwise.
Its always best not to damn someone else--certainly not in public if you dont know the reasons for the decisions they made and certainly if they are not in a position to respond. Most of us know that design is always a balance between form and function and perfection is impossible because we all see things from differing points of view.

[shh120m]

il stay out of this one BUT,

is the point of building to get it finished and drive it to have FUN,

yes there may be compromises here and there for some reasons or another, i dont recall ever driving the "perfect" car, and iv had a few quick motors.

Once youre on the road in a haynes all this crap about handling is soon forgotten and replaced by a big grin (unless marks driving ofcourse then its sheer fear )

[Bonzo]

Originally Posted by shh120m

Once youre on the road in a haynes all this crap about handling is soon forgotten and replaced by a big grin (unless marks driving ofcourse then its sheer fear )

Wait till you have a ride out with AshG

I done a very childish thing in Ash's car .... Found out that adrenalin was Brown

[davidimurray]

I think you need to consider the context in which the Haynes Roadster is designed - i.e. it is a 'sporty' road car, for occasional track use, based around a single donor.

As such you begin with a number of design constraints, in terms of suspension you have the uprights and brakes to contend with as a starter. In an ideal world you start at the tyre and design backwards, through the upright design , wishbone and then finally the chassis, which at the end of the day is only there to connect everything together. Of course to do all this you need a set of target design parameters to aim for - to do this you have to make a number of assumptions, such as the CoG. There will be a number of driving conditions to then consider - e.g. high speed cornering, low speed cornering, braking, acceleration and all the combined load. A car setup for low-speed autocrossing would be totally different to a high speed circuit racer.

Unfortunately for us we want the roadster to be all things to all men using a number of predefined parts - so the poor car is up against it to start with.

There are plenty of possible improvements you could make - e.g.
Re-designed wishbones with rod ends - although you would need to redesign to prevent rod ends in bending. Also for correct adjustment rather than having adjustable rod ends, staked in bearings would be better along with packers on brackets at the upright - so now you need new uprights.
Then of course there is the round tube chassis - but why even use tube when you could build a excelite monocoque. You can go on and on for ever!

Having been lucky enough to be involved in project managing the build of a simple single seater, while not a designer myself, I've been invovled in quite a few discussions and basically every decision is a compromise of time, money and engineering.

So having been involved in building such a car - why build a roadster?? Because I want a good fun road car that I can have some fun on track in and more importantly build it all myself.

Ramble over

[monsterob]

Ive messed around with all the critical bits on mine ! Rear hubs front hubs wishbones are longer blahh blahh havent a clue how its all going to work or even if it will atall, i know bugger all about suspension hence using four bike shocks instead of the coilovers .

Its a hobby if it doesnt drive ill sell it on ebay to some unsuspecting mug as an unfinished project

Or just weigh it all back in as its all scrap anyways !!!

[MarkB]

Oppsy I upset the spoons........

[minicountryman1961]

Originally Posted by MarkB

Oppsy I upset the spoons........

If you are having trouble getting your Roadster around corners, you should add rear-steer.

[robo]

Originally Posted by minicountryman1961

If you are having trouble getting your Roadster around corners, you should add rear-steer.

Its all a load of crap, every car maker in the world builds in understeer in the car to stop people overcooking it in a bend and loosing the back end which in their opinion joe public could not control.Anyone can reverse this with set up and with a little friggin dial in a neutral or oversteering car.

Bob