I did 4500 on my 748s and the rear brake worked just as well as any honda i had before could lock it or just drag it abit to brush off speed on wet corners. I think it maybe due to using it a lot slow speed during commuting nealry every day.
On the S4r i have now the caliper is in the same position looks to be the same caliper to. but the master cylinder is away from the engine and at a 45 degree angle and it works very well

