Traction control, wheel speed sensors... who wants 'em?

[tweiss3]

Any pictures of the problem on the rears? And couldn't you just make the teeth not so tall on the rears?

[TitaniumTT]

Negative, no pics of the problem, it's pretty simple really, the diameter of the trigger wheel is bigger than the diameter of the inside of the rotor.

The problem is the back of the flange, it has wheel studs on them. The wheel studs are 20mm's in diameter. The flange also has M8x1.25 on a 114.3x5 bolt pattern, the same pattern of the studs. So, in order to make a solid piece of steel that will bolt to the back of the flange, the base diameter of the trigger wheel needs to be (114.3/2) +10mm + enough meat to hold the teeth (I'm using .1875"). Then you need to add in the .7" required for the teeth. This result's in an OD that is just to big.

The REAL problem is the sensor is mounted on the wrong axis. The sensor's are designed to point at the axis of rotation, not with it, thus dictating the size of the teeth.

My original plan was to just use the drive flange and some spacers to push the wheel to where it needed to be. The problem with this, is again phyical size restraints. The bolt pattern is 114.3 or call it 57mm's. Subtract from that the 7-8mm's needed for a bolt and washer and now we're interfering with the 100mm boss that holds the bearing. So that doesn't work either.

The simplest was to do this, like I said, is with a .25" plate of AL cut in a circle, with 24 or 12 or even 5 evenly spaced holes drilled and tapped to 10-24, M6x1 or 1/4-20 or even M8x1.25. The you simply thread bolts into the plate from the wheel side and lock them down with nuts. This accomplishes the spacing to the sensor, and provides a signal. I've already built 2 of these because I was desperate for wheel speed signals before last years DGRR. Now that I've got the time and the space, I'm ditching those and opting for the lazer cut wheels because, well, they'll be more accurate, they're sexier, and I can in my application becuase I'm replacing the rear brakes. The CorkSport RZ FD brake upgrade MAY work, I don't know, you would need to call them and find out what the ID of that rotor is .25" up from them inside mounting surface.

Yet another option.... Using the originally cut trigger wheels that fit inside the rotor, bolt them to the flange intop of the back of the studs and get a thread in hall effect sensor or even a mag sensor. You would then need to have a bushing machined to fit into the stock sensor location and tapped for whatever the sensor threads are. This will allow you to keep threading the sensor into the brake rotor until it is at the proper clearance to the trigger wheel.

There's more than one way to skin a cat and I've been juggling this problem around my head for over a year now so I've got a bunch of different ways to solve it.

[tweiss3]

Good deal. I can clearly picture the issue. Its quite unfortunate, however shit happens. I guess based on that I would be forced to back out.

[TitaniumTT]

No worries, I figured most will. I'm going to keep the files so if anyone wanted them in the future, you'd be able to send the files to a waterjetter or lazer cutter and get the front's done at least. Rears are going to be a constant problem until I get a lathe.... damnit, I need machinery

[tweiss3]

what's the file type you used for these? Years down the road when i would need these, I have enough connections to figure something out. Thanks for the offer on getting these things mass produced for cheap.

[jrx13]

Just found this thread. I'm looking at adding wheel speed sensors to all four wheels for my datalogger. I see the last post where the rears won't work too well. Did you ever get the fronts made? I tried to come up with a way to mount a sensor in the front aimed at the back of the wheel studs, but they are too recessed.

I'd be interested in a set of your sensor rings for the fronts. Right now I'm trying to source abs sensor rings, but I see you tried that already too.