HOW TO: Quick and Easy ABS Disable Switch
- Thread starter moespeeds
- Start date
In each wheel there is a phonic disk. for each wheel there is a sensor actuated by a magnet. For each sensor there are two cables (one for a constant analog signal, and the other cable is the return of the signal but in pulses, through the phonic disk and the magnet)….if you want to eliminate the rear abs only when you want…. you will need some wire, some electrical tape, 2 relays and a switch… the switch is to feed or not the relays, some wire is to use the rear stop light signal and activate the relays…. and the rest of the cable is to get the pulses from the front sensor and send them to the return cable of the rear sensor, so the ecu will believe that the rear wheel is turning at the same rate as the front one…..it would only work with the rear brake….if you use the front brake...the front abs will still work, as will the combinated brake..
You need to use 2 relays actuated by the rear brake light. a normal closed relay so that the rear turn pulsed signal returns by the rear pulsed signal return….and another normal open relay with the front wheel pulsed signal…..when you step on the rear brake, the rear stop signal, It will open the first relay (interrupting the rear pulsed signal), and close the second relay (introducing the front pulsed signal, into the rear pulsed return cable)…..The ECU, would not find out what is happening
It is a theory, and like any theory, the demonstration is the most important thing. I personally haven't done it because I don't need it, but if I really needed it, I think the rear abs problem, I would solve it electronically that way to be able to "turn the rear abs on and off". Connecting a direct line from the master cylinder to the rear caliper also works, only it would be permanent and you would lose the combined brake..
Unless (another theory.
.) a "Y" circuit was used...where you could "close" the brake circuit that goes from the rear pump to the abs/caliper and open directly from the pump to the caliper (when you don't want rear abs)…..and when you need it, you close the direct circuit and open the way from the pump to the abs and from there to the caliper ….there are “selonoids” that command this type of fluid passage and that handle hydraulic pressures much higher than that generated by the brakes…..These solenoids are really small...
In the pic, you can see a "Y" hydraulic system (one rear input and two outputs)... and a solenoid at the tip that makes the change for one or the other circuit. And in the second photo you can see more or less the size of the solenoid
Unless (another theory.
.) a "Y" circuit was used...where you could "close" the brake circuit that goes from the rear pump to the abs/caliper and open directly from the pump to the caliper (when you don't want rear abs)…..and when you need it, you close the direct circuit and open the way from the pump to the abs and from there to the caliper ….there are “selonoids” that command this type of fluid passage and that handle hydraulic pressures much higher than that generated by the brakes…..These solenoids are really small...In the pic, you can see a "Y" hydraulic system (one rear input and two outputs)... and a solenoid at the tip that makes the change for one or the other circuit. And in the second photo you can see more or less the size of the solenoid
Although there is a difference between the rotation of both tires... that is compensated by the ecu so as not to activate the TCR prematurely. The abs comes into action when there is "braking pressure", "deceleration" and above all when the rotation of "one" wheel decreases so much that it approaches blocking or that it blocks... but if the pulses indicate that it is rotating ...abs shouldn't decrease brake pressure...but if you applied "both brakes" and "both wheels" tended to lock up...there would be no way to compare rotation...in that case it's the brake pressure, together with the deceleration sensor , those that avoid blocking
I didn't quite understand everything. How can the TCR work if the pulse comes from the front wheel when the rear ABS is disabled. I think ECU compares the rotation of both wheels and activates TCR if the rear wheel starts to rotate quicker.
What do you mean by deceleration sensor? I think the ECU detects the change in wheel speed based on the pulses from the ABS sensors and just reduces the brake pressure several times per second if the wheel speed drops too much or the wheel doesn't turn at all.
What do you mean by deceleration sensor? I think the ECU detects the change in wheel speed based on the pulses from the ABS sensors and just reduces the brake pressure several times per second if the wheel speed drops too much or the wheel doesn't turn at all.
“”Ididn't quite understand everything. How can the TCR work if the pulse comes from the front wheel when the rear ABS is disabled””
Normally, when you accelerate (TCR), you are not braking at the same time (ABS). If with relays, you disable the rear abs “only when braking”…..when accelerating, the rear wheel pulses will be from the rear wheel (useful for TCS)
“”What do you mean by deceleration sensor?”
deceleration sensor = chassis speed
Normally, when you accelerate (TCR), you are not braking at the same time (ABS). If with relays, you disable the rear abs “only when braking”…..when accelerating, the rear wheel pulses will be from the rear wheel (useful for TCS)
“”What do you mean by deceleration sensor?”
deceleration sensor = chassis speed
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The manual has dozens of pages on the activities of ABS and UBS. It seems that modern electronically controlled ABS brakes are so complicated that it is not easy to stab them. In any case, there is no guarantee of achieving a reliable end result. At least I'm not going to start any pilot project myself. I guess I have to settle for not being able to lock the rear wheel even on gravel roads, although a big part of the driving pleasure is lost when you can't steer the bike by locking the rear wheel. Braking distances are also longer, in that sense I consider the absence of the option to switch off the rear ABS as a serious deficiency and a human rights crime.
Tenman
Well-Known Member
That's deep.
patrickg450
Well-Known Member
TWSS
Pappaclutch
New Member
Does the ABS work when the bike is off? Let’s say you are at the top of a loose steep hill and you flip the kill switch and use the breaks/engine breaking until you get to a safe spot flip the kill switch back on pull the clutch and start the bike, presumably on the move?
It would be the correct and safe way to descend a steep hill, without modifying the abs system
You can stop the engine, (and start it again) and if the speed of descent does not exceed the speed of activation of the abs....you can descend the steep hill without abs
You can stop the engine, (and start it again) and if the speed of descent does not exceed the speed of activation of the abs....you can descend the steep hill without abs
thughes317
Well-Known Member
Not to my knowledge. Disabling rear-only will require either a mechanical solution (brake line bypass, which would be a permanent disable) or switching to another ride.