Motorcycle stores in Sao Paulo, Brasil
 

Are you looking for motorcycle stores in the centre od Sao Paulo? They're all centred around the streets leading off Rua Guaiananes. If you stick this co-ordinate into Google Earth you'll find them:

23°32'17.29"S 46°38'32.74"W

I was in search of a tire for my F650GS and there were plenty of tires in stock in all sizes. Brands readily available are Michelin, Bridgestone & Pirelli. If you're lucky you might find a Metzeler.

Prices ranged from 280R - 360R for a rear 130 - 80 -17 tyre. I kept walking around and managed to find someone selling a Michelin Sirac for 170R (approx $100USD). I got it fitted at a workshop for 20R

If you're looking for BMW Motorrad in Sao Paulo they're very close to Ave Paulista. When I spoke to them they were very friendly, one of the mechanics there speaks English:

Caltabiano BMW Motorrad Oscar Freire
CARROS (veículos): usados (seminovos) e novos (0km) – Caltabiano
R. Oscar Freire, 1233 - Cerqueira César
São Paulo - SP, 01426-001, Brasil
(0xx)11 3891-3000

Another good option, in the area you mentioned (known in Sao Paulo as the General Osorio area) is Moto Atacama:

Moto Atacama

The owner is very friendly and also has been traveling round all of South America on a F800GS and a V-Strom. Good parts and services. Also has a clothes and equipment shop upstairs.