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lenny
May 24th, 2006, 5:47 pm
how much brake should i have with the bike not running?
TandemCyclist
May 24th, 2006, 5:52 pm
how much brake should i have with the bike not running?

Ignition on and good battery normal brakes.

Ignition off, look out it's not going to stop very quick. No servo motors.
lenny
May 24th, 2006, 5:58 pm
i know that but any brakes at all?
andy
May 24th, 2006, 6:01 pm
Yes, you still have 100% stopping power, you just have to squeeze a little bit harder. Essentially you are back to a bike without servo's
Petre
May 24th, 2006, 6:46 pm
What brakes ? :p
lenny
May 24th, 2006, 8:33 pm
i have zero brakes with the bike off
jzeiler
May 24th, 2006, 9:25 pm
I know that is what it feels like compared to the power on brakes but I can stop just fine with a very hard squeeze of the lever. If you don't have any brake at all with the key off then you may have a small amount of air in the control circuit. It will work well with the servo assist but not pass enough pressure with the servo assist off. Best to have the bleed test done at the dealer soonest.
mneblett
May 24th, 2006, 11:48 pm
i have zero brakes with the bike offBetcha don't. Squeeze harder. Seriously. And practice so you get used to it. These brakes are *exactly* like car power brakes, in that when the engine is off, you lose the "boost" and have to press the lever (pedal) harder.

I've seen the insides of the Integral unit, and have eyeballed cross-sections and other drawings. There is a definite physical (hydraulic) connection between the levers and the calipers, via intervening pistons in the Integral unit. When you squeeze the lever, the intervening piston is pushed forward by the control circuit pressure, and the other end of the piston applies pressure in the wheel citcuit.

The relative sizes of the components and the lower force generated by your hand vs. the electric pumps means that (like a car) the unboosted pressure in the calipers is significantly lower, but the bottom line is that there is *always* braking capability present. Would anyone seriously believe BMW would not have designed in such a built-in, failsafe capability?? (lose electric power and have *no* brakes? not in this suit-happy market!)