Unique Speed Sensor

[DENVERUFO]

Thought this blurb would be more appropriate here as it is relative to new fabrication. I've posted pix of my new bike in other areas so most probably know what it looks like. Anywho....I had to have a way to sense the speed accurately and most of you know that I have a homemade contraption bike as opposed to a HD. So I don't have a regular transmission, but a snowmobile CVT. Where do I sense the speed? Can't be on the rear tire (trailer type) as it expands as speed increases. On the front you say? Well, I have a 95 RK h with the electronic speedo. But I found a way to put it on the front but not with mechanical sensing but with the same HD transmission sensor.

I started with a Honda disc and attached a cutout pattern that I could grind away in the shop.



The grinder seemed to work out OK and made great cutouts. I just had to rotate it every now and then due to it getting hot. I wonder why?..lol.



After about an hour or so grinding....I got all 96 teeth cutout. How did I come up with 96 teeth. Well I started out with the HD info relative to the frequency required to equal x mph. Then I copped some RPM vs Wheel Diameter vs Speed calculations. Churning all this together I came up with 94 teeth required. Here is the finished product after all the grinding and smoothing.



I actually ground in 96 due to the pattern drawn. That is OK as it will only show up as a higher speed on the speedo relative to what I am actually doing. As I trim down to the correct speed....all I need to do is grind off a tooth or two till I get as accurate as I can. I am aiming for 55mph accurately. Next is what it looks like attached to the wheel.



For a close in look...see this next shot. I have the sensor ~0.1" away from the disc. Tried it out and it looks like it is pretty close to right on. Works smooth as a baby's ass. Made the mounting bracket with a little welding and drilling and it easily attached to the fender bolt.

[rodbender]

Unreal. That is fucking cool!

[junior]

again, kudos denver. well researched and thought out. sometimes the most time we spend on what appears to be an insignificant detail to others, but is of major importance to ourselves.

when i built my first tc88 custom there was no information about how the ignition worked. the aftermarket had only started eveloping modules, but this assumed you had the whole wiring setup.

i had a frame and an engine.

like you, i had to spend quite a few hours understanding how things worked. eventually i got some resistors at radio shack and away i went.

well thought out and clean denver...

j

[Blackcloud41]

McGyver! And I mean that in a good way!

[Old_Evo]

Thanks for posting this. Just great. Doing your own custom work on any bike truly makes it your own tho I believe it's been yours for a long time now. That really is a great bike you have.

[Relic]

That is sweet. Good idea, Bro.

[Bigshovel]

I think it's bas, you have way more patience than I. I wouldn't be running a speedo if I had to do all that LOL, good job.