radial vs axial uprated front callipers - AP

[Doctor]

Anyone tried to change them? (the hub change is required as well)

 

Just keep looking at them on the online store - looks quite tempting.

 

Some experience please - for instance even people having 620R then driving the car with uprated brakes with axial mounting - I'm interested in the comparison. Is there a difference?

[Mark w]

If there is a difference I would say it's marginal .

Cannot say I notice much difference between the brakes on my 620 and the old R400 .

Changing pads on the new ones is more time consuming as you need to remove the caliper ( retaining pin for the pads clashes with the wing support ) 

[ChrisC]

And the original bolts used to secure them to the uprights have caused a lot of owners problems to removing them.

[Doctor]

Should I leave it alone then?

[Doctor]

I have a CSR, so my wing support might be different to yours. 

[Doctor]

What is the solution to this?

[Mark w]

https://www.lotus7.club/forum/techtalk/front-caliper-torxstar-bolt

You best read this thread .Been there done that ! 

[ChrisC]

Remove the original bolts, and replace with normal cap heads, and a more appropriate strength and quantity of thread lock. 

[Doctor]

Mark, the recommended thread only describes the issues with the bolts and the odd assembly...

 

What I need is someone telling me - yes, buy these, there si a massive difference to your axial ones or don't bother, there is no difference.. After all, the glossy black radial caliper is the same size as mine axial matt black (both four pots).

 

Is the yellow one on 620R any bigger?? What about that grooved brake disc? Is that still 10inch?

[ChrisC]

Can't imagine its much larger, there isn't much space in the 13" wheel for anything larger, you already have to be careful where the wheel weights go.  But as you said they are grooved ;-)

[Mark w]

Doctor I don't think the yellow caliper is any bigger . As far  as I know I takes the same pads .

My car was one of the first 620R s it has the yellow calipers but the disc is plain not grooved . I think they are interchangeable .

[Mark Durrant]

Why do you feel the need to change the brakes as many CSR race cars with 300+BHP run with the standard big brakes without any issues. I would optimise what you have, maybe change the pads and spend the money saved on driving the car.

[Pendennis]

Yep as Mark says get the right pads and play around with brake bias.

[Doctor]

Just put in Ferodos DS3000. Can'r wait to see the difference.

The reason I started to explore this avenue is that I know from the bikes that the radial calipers twist less (due to the way the force is being transferred) under braking...

[Mark Durrant]

I expect given the lightweight of a Caterham the wheels will lock before any twisting takes place.

[Doctor]

Hi Mark, fair enough, why would they then change the fittings of the caliper if no technical reason? Marketing? It is a shame my car has the old style as it was finished in August 2014, with the new style calipers being available since February 2014...

[ChrisC]

It's a guess, but I suspect the change was to replace the standard hard to get triumph caliper with an off the shelf two pot AP caliper.   This also means both new calipers are standard AP calipers (obviously with caterham logos), so it might have reduced manufacturing costs as well.   The down side being the extra effort required for pad replacement.

[ChrisC]

I was expecting a change to the rear calipers as well, but it looks like caterham (from the parts website) has got sierra rear calipers remanufactured in Taiwan since 2016 instead of using reconditioned units. 

[Doctor]

CSR has a slightly different caliper at the rear. 

[Mark Durrant]

I expect the availability and supply of parts is the likely reason.