Just had a cyclist ride straight out in front of me from a blind drive.
Emergency braking locked up the rear wheels but not the front.
Is this normal?
I can confirm (as yet another car today didn’t see me and pulled out in my path) that I can controllably lock the front if needed. The rear wheels don’t appear to lock. That was around 30mph. To achieve maximum braking I thought it was normal to have the greater braking force biased towards the front were the larger mass is. Isn’t that the laws of physics?
It depends on the weight balance front to rear. For example the mk1 MR2 that NeilM and I Hillclimb is light on the front weight is 40% front and 60% rear axle. Now under normal braking everything is fine but if you want to stop quick regularly, especially in the wet or damp it is easy to lock up the front. After a bit of research on MR2 race forums we found that the best way to resolve this was to fit a brake bias valve on the fronts, not the usual way to do this. The valve is set to about 20% more to rear! it is a progressive valve so under normal braking split is 50/50 but if you brake hard it will be 40% front and 60% rear roughly. The effect of this is it helps get the nose down on the front suspension just as the front brakes start to exert force. Anyway it works and I would guesstimate that we have shortened the braking distance by about 35% from standard set up.
As said earlier on a MOG under braking the weight transfer is more up front hence rears locking, however the rear axle is pretty heavy and can act as a pendulum and induce tail hop. I experience this in my plus 8, a
experience. This can be induced by accelerating in a turn and the quickly braking and then turning the opposite way to correct. The car will tail hop from side to side, or snake, I would not recommend trying it unless in a very open flat area off road. If you brake harder the tail will come right round, the way to get rid of it is accelerate out of it.
