The Obtainable Brembo GP4-MS, GP4-RR, GP4-PR, GP4-RS, GP4-RX and Unobtainable Brembo new GP4 caliper


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Since MotoGP is on break for a month I still needed my fix and fortunately stumbled on Sylvain's channel - Among all the technical info he also goes into pricing @6:45min but here's the package each rider receives each year excluding additional wet setups or crash damage (+$$$). They are assigned 3x Master Cylinders, 6x Calipers, 10x Rotors & 28 Pads costing €70 000 + vat = €84 000 or roughly $100 000USD (V4SL anyone?)
So while this thread is dedicated to Brembo's caliper range the rotors certainly can't be ignored, specifically carbon as the technology for more than just racing application is obviously going to become more available before too long. Following the SBU V4R build and seeing them trying out the Sicom rotors albeit on track got me searching for viable street options and lead to the Braketech Axis/CMC - discontinued, under development, awaiting production...?? Anyway kind of short & vague post, just thinking out loud really but its got me nerding out a bit and maybe I'll try find a way to incorporate something in future with my ongoing bike project.

BMW Alpina

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I just found out that the new Brembo GP4-RR in 100mm caliper bolt spacing is ready for order at WRS.IT
Last year, they are only available in 108mm caliper bolt spacing.
I don't think they have this new 100mm version in stock yet, because only WRS listed it and no other store listed it. Here is the Part# XB9L2A0
But I did find the part# in Motoquality catalog (the Brembo main distributor in Italy), so this caliper really exist.

and here is the link: XB9L2A0 PAIR BRAKE RADIAL CALIPERS BREMBO RACING GP4-RR 100MM P4 32/36 2021

This means, it allow to use the stock Ducati Ohlins shocks with 100m bolt spacing, however, the offset is 22.5mm so you will need spacer on the brake rotor.
Another interesting spec is the piston is 32/36mm in size and the same between the 108mm and the 100mm version.

WRS also have a USED 2020 WSBK caliper, (unfortunately NOT the one with the cooling fins) for sale on their website: XC09110+XC09111 BREMBO RACING USED RADIAL BRAKE CALIPERS KIT WSBK 2020 CHAMPIONSHIP
and the price is 6,699 EURO (please note this is price for USED pair of calipers).
This WSBK caliper has piston size of 30/34mm so both the GP4-RR above and this WSBK caliper will need a larger MC than the stock MC, or if you use RCS Corsa Corta, it will be the RCS19 Corsa Corta.

Here are the pictures of the 2020 WSBK calipers:
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