Atom 4 first drive

[jaylatti]

https://www.facebook.com/groups/ariel.c ... 635841342/

[jaylatti]

https://www.facebook.com/groups/ariel.c ... 683146342/

[apr1962]

Jay
Do Ariel fit the updated bushes by default now, or still use the standard ones?
I like the arm rest in your car. Are they available to buy.
Sad I know
Thanks
Andrew

[jaylatti]

I think the uprated bushes are an option rather than by default but just going on what others have told me so best to check . Here's a link to my armrest solution lol https://www.facebook.com/groups/ariel.c ... 001651342/

[willox]

Some good reading and views.Purchased Ariels ex demo Atom 4 couple months back and have only just driven it proper this week having done a few hundred miles this week..

Never really seen an Atom before purchase so new to me and in for a surprise, here is my thoughts on it so far...

I'll start with the brakes and I'm glad to read they come with Ds2500 with the Ap racing brake kit with 2 piece discs...they feel like Ds2500,utter garbage for my liking.Brakes are non existent when cold, along with cold tyres find them tricky to navigate.Need proper warming up along with tyres and to be fair, work well once all up to temp but I can see me change the pads to DsUno or something along that lines to improve initial braking from cold and also improve the pedal to get some more bite in that soft spot.Once you are on the brake, sits down nice beside the throttle for heel and toe, pedal offset also which getting used to.would be perfect for left foot braking with a sequential gearbox!

Gearshift is better than expected going by reviews, sure I have uprated bushed.Doesn't give much confidence at a standstill but getting through the gears with no issue when in use, only downside if shifting gears real quick, feels like could be rasping the odd synchro so ill try not throw them to hard.Shifts with ease,on the light side but acceptable.

On the road, wow!! shockingly nice to sit in and still trying to get my head round lightness/understeer when you start to push?light lift of throttle all comes in again easily.have the Ohlins fitted and cant fault the ride.

Noise,2.0 turbo with straight exhaust and an intake in your ear...well,its loud but acceptable with the helmet and imagine even better with ear plugs fitted.

Power is pretty awesome but the engine feels to lack any shove at the top end of the revs.Find myself hitting the rev limiter a few times due to this but making use of the shift lights helps.Its pure torque all the way and thats it really, feels like it comes on strong and if anything fizzles out at the top.Guess torque will start to drop off 5k ish ?? can easily short shift, pulls from next to nothing and for what it is as a complete package,'m hugely impressed!!

I will be chucking that 2500's if thats what I've got so ill update back when I change these out.Thats only downside for me at the moment and its a minor thing but sure could be better.Had 2500 pads before and hated them so confident will be all good.Ap stuff is quality.

So far no regrets, love it and is a total new driving experience to me.whether the novelty wears off,i'm not sure but its a proper piece of engineering and a total driving hit,cant wait to book a track day with it.

[CharlesM505]

Interesting discussion here re the brakes. So, I can't comment on the A4 being on the wait list still, but I have a Lotus Exige 420 which has the 2 piece J hook AP's with DS2500 pads so I feel there is some credibility in sharing my experience! I have so far done 3 trackdays with the car. On the Lotus I would say they work well both on road and track, although definitely better with more heat.

Perhaps it's the low weight of the Atom which makes it hard to generate enough heat unless you are really pushing?

[mynamesnotbob]

The servo on the Exige means there is much more assistance and the master cylinder is different.

Completely agree however that the 410/20/30 platform were a cracking brakes (ex owner here), by comparison the feel is significantly up on the Atom, far closer to an S1

I agree the pedal is long, however very solid stopping power once worked, it was mentioned earlier around a larger master cylinder- this would give the same pressure for less travel so could be an option, I’ve done it in the past and it’s worked. I would say I got more used to it after a week of driving, happy with the pressure but just want less travel.

Will likely switch to Carbotechs as they transformed the brakes in previous cars, and will adjust compound based on need/desired feel, but still think the master cylinder needs expanding to reduce travel but keep the same pressure

[willox]

I'm just going to put the brakes down to the ds2500 if thats fitted and get something with more cold bite.Cant fault the stopping power once the pads and tyres are all up to temp.See how pedal goes on track,dont feel so soft when driving to sat stationary.Stick away with Ferodo Racing,ran Xp10 Carbotecs in another car, also very good pads with plenty bite.

[IanG]

Update on my first impressions
So same car has been back to the factory for a service and a brake bleed as this is what was recommended by the factory
The brakes are now on a par with the Alcon set up ,
Result as they now bite and inspire confidence when stopping.

Now for the strange one
Having worked on cars for 40 years I can’t understand how bleeding the brakes has changed the brakes so much ,it’s only a transfer of fluid so my thoughts are

New pads have been fitted plus the bleed
A valve has been replaced in master cylinder plus the bleed
Bleed only not convinced
I am willing to be proved wrong.

[Monza]

I don't know if i'm supposed to write here about the new bleeding process, but i'll do
It appears that the main reason for long pedal travel with near no effect on braking is because the pistons in the calipers are going backward during driving between each braking, so the first travel of the brake pedal will only push back the pistons/pads closer to the discs and, only after, it'll begin to really brake.
The new bleeding process is here to correct the problem, with putting "more " fluid between the pedal in rest position and the pistons so that the pistons can't go back so much when pedal is up/rest. The consequence is that, after this special bleeding, the pressure on the discs is quick, there is no longer dead travel only to push the pistons/pads back in contact with discs.

Every one can make this test : after some driving press the pedal a first time, release it and push it again immediately : the pedal on the second pressure will be firm and braking near immediat (pistons didn't have time to go backwards).
Hope this helps

[reg]

How does bleeding change the dynamics of the pistons going in and out? It’s just moving fluid? There’s either air in there or not?

[Monza]

If the pistons are going back it's because they have "place" to do it. Imagine the hydraulic a little but on pressure, it's similar effect with no pressure but no possibility to go to much backwards.

[IanG]

If the pistons are going back it's because they have "place" to do it. Imagine the hydraulic a little but on pressure, it's similar effect with no pressure but no possibility to go to much backwards.

So in a sealed system

How can you get air in the system (you have a leak)
Or you have left air in the system when installed.

Brake fluid being hygroscopic, so any air in the system means that the fluid is absorbing moisture.
Not good as it makes the peddle soft.

[reg]

If the pistons are going back it's because they have "place" to do it. Imagine the hydraulic a little but on pressure, it's similar effect with no pressure but no possibility to go to much backwards.

Yes, air in the system. There is no magic compensation, the piston pushes and pulls fluid. If the fluid contains air, the pedal will be soft and the system will not do it's job. So maybe they have found how to remove all the air.....

[stupot]

Steve told me the issue is exactly as Monza describes when we spoke to book my car in for it's first service. I get a firm pedal and good feel on the second press so my pistons are retracting back too much. Steve did explain they have a new process so will let them do it at the first service.