Upgrading the ‘23 V4R front end

Spooky

Member
These are the billet CNC master cylinder, they are really good quality i just bought the 18x18 to try.
Did you try it yet? I assumed you meant the 19x18.

I’ve bought the 19x18 CNC master to try out of curiosity - if I don’t like it then it will be perfect for a brake upgrade on my SportClassic.

I went for Extreme Components clip-ons - they have the cut-out for the locating lug on the OEM upper triple, which is handy, plus the mounting point for the steering damper. They look like they are good quality.

image0 2.jpeg

The Jetprime QA and throttle arrived but they put the wrong size screws in the box, so fitting it all on the bike will have to wait until the correct screws arrive…

The GP4-MS with fins are now available to order. Whether they actually arrive on the suggested date is another matter of course. I’m tempted to treat myself because they look cool but I’m not sure they would actually be an upgrade. Titanium pistons for the OEM Stylema might be better (or with the GP4-MS). What’s the recommended option for titanium pistons (I’m in the EU and would ideally buy within the EU).

GP4-RR are available in 100mm and I guess they would be an upgrade, although an older design. Different offset if I understand correctly.

Accossato calipers seem reasonable value with the correct offset and titanium pistons. 34+38 pistons though.

GP4-LM are more than I’d want to pay.

I’d guess upgrading calipers to anything other than 4x30mm pistons would mean bypassing ABS would be essential? I presume it’s based on assumptions about piston size and increasing that (at all or significantly?) would be a problem for the electronics?
 

Bruce Wayne

Well-known member
Did you try it yet? I assumed you meant the 19x18.

I’ve bought the 19x18 CNC master to try out of curiosity - if I don’t like it then it will be perfect for a brake upgrade on my SportClassic.

I went for Extreme Components clip-ons - they have the cut-out for the locating lug on the OEM upper triple, which is handy, plus the mounting point for the steering damper. They look like they are good quality.

View attachment 13716

The Jetprime QA and throttle arrived but they put the wrong size screws in the box, so fitting it all on the bike will have to wait until the correct screws arrive…

The GP4-MS with fins are now available to order. Whether they actually arrive on the suggested date is another matter of course. I’m tempted to treat myself because they look cool but I’m not sure they would actually be an upgrade. Titanium pistons for the OEM Stylema might be better (or with the GP4-MS). What’s the recommended option for titanium pistons (I’m in the EU and would ideally buy within the EU).

GP4-RR are available in 100mm and I guess they would be an upgrade, although an older design. Different offset if I understand correctly.

Accossato calipers seem reasonable value with the correct offset and titanium pistons. 34+38 pistons though.

GP4-LM are more than I’d want to pay.

I’d guess upgrading calipers to anything other than 4x30mm pistons would mean bypassing ABS would be essential? I presume it’s based on assumptions about piston size and increasing that (at all or significantly?) would be a problem for the electronics?
Haven't tried it yet, it's an 18x18 will hopefully get a chance next couple of months, im still recovering from a MX crash my shoulder is not great. I have a set of GP4 MS calipers on the V2 i fitted titanium piston. V2 is all finished just need a new shoulder to let me ride it

IMG_20240405_131207.jpgIMG_20240405_125814.jpg
 

Spooky

Member
Haven't tried it yet, it's an 18x18 will hopefully get a chance next couple of months, im still recovering from a MX crash my shoulder is not great. I have a set of GP4 MS calipers on the V2 i fitted titanium piston. V2 is all finished just need a new shoulder to let me ride it
Looks great. (y)

I’ll be very interested to hear what you think of the 18x18.

Hopefully I’ll get my 19x18 fitted soon and see how it is with my OEM Stylema.

Get well soon!

So, my upgrade options seem to be:

- Titanium pistons on the Stylema as they are plenty good enough.

- GP4-MS - probably no noticeable performance benefit but pretty with the fins (non-finned models about 500 Euros cheaper and actually available rather than hopefully by the end of June… but we all know what Brembo have been like).

- GP4-RR - come with Titanium pistons as far as I am aware and also 100mm, but I suspect they would not be a good idea with ABS in place as they use much larger pistons?
 

Spooky

Member
I fitted the Extreme Components clip-ons today. Unfortunately, they do not seem to work with the OEM brake lines. I guess because of less offset but the lines seem very tight and I am unable to turn the levers down much. Rather disappointing.
 

Spooky

Member
Spider 42mm offset clip-ons arriving on Monday along with the upper triple, so I should be able to get everything fitted this week as I don’t expect issues with these. That will allow me to fit the 19x18 master cylinder and I’ll be able to try it at Brno at the end of this month. I finally got to ride the bike at Most a week ago - absolutely love the bike. The stock master cylinder obviously works fine but it is a little bit vague and I reckon it can certainly be improved.

I’ve made the mistake of looking at the Pierobon website… :rolleyes:

I’ll look into the brakes side of things at the end of this year, depending on how I progress through the year.
 

Spooky

Member
@Bruce Wayne Have you had the chance to try your master cylinder yet?

With the 19x18 after a few sessions, I’m finding that my entry speed into corners has slowed down. It doesn’t feel wooden, but perhaps there’s not quite enough modulation.
 

Bruce Wayne

Well-known member
@Bruce Wayne Have you had the chance to try your master cylinder yet?

With the 19x18 after a few sessions, I’m finding that my entry speed into corners has slowed down. It doesn’t feel wooden, but perhaps there’s not quite enough modulation.
Have tried the 19x18 but not the 18x18 yet what pads are you using? You don't have to use a lot of pressure with this MC might take a bit to get used to it, just need to gently squeeze on entry and adjust pressure accordingly As you approach the apex, if y just grab a big handful at once you wash off all entry speed. I think after a short time you will get used to it
 

Spooky

Member
Have tried the 19x18 but not the 18x18 yet what pads are you using? You don't have to use a lot of pressure with this MC might take a bit to get used to it, just need to gently squeeze on entry and adjust pressure accordingly As you approach the apex, if y just grab a big handful at once you wash off all entry speed. I think after a short time you will get used to it
Z04 pads.

I tend to be light and long on brakes and I found was having to brake later, which isn’t necessarily a bad thing of course, but the difficulty was modulating the release into the corner. I was getting used to it at the end and still managed to go faster at that circuit than I did before, but I’m not sure it suits my style.
 
Top