Billet Start/Stop switch with tach, need your inputs

sfab

sfab

X
Location
Canada, QC
Ive been designing a cheapo tach for my SJ for almost a year (on and off) and came up with the idea of making a start stop switch with an integrated tach. This include the start/stop buttons and a function button to monitor the RPM vs elapsing time to estimate the fuel consumption with an adjustable ratio. Waterproof billet case, SS bolts, lexan display window....
I know this thing may be overboard for must of you but i thought it looks cool enough to show it to the world! :biggthumpup: And it can be a good tool to check the actual RPM and estimate the current speed.
I will be running this thing this season to see if the electronics will last...

Honestly, what do you thing of my new gizmo? :bananapowerslide:
BTW, it missing the buttons on the pics because theyre not machined yet
 

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DAG

DAG

Yes, my balls tickled from that landing
Location
Charlotte, NC
its tuff to make things waterproof.. hell our ski's have hoodseals and their is a rubber gasket between the ebox, and water get's in them all the time..

but i think its kick ass,, neat gismo, i dont think i need to check my rpm all that much though... i should be looking at my setup wake.. but if you can program it to make the prefect pass, i'm sold :)
 
Mouthfulloflake

Mouthfulloflake

ISJWTA member #2
Location
NW Arkansas
man you must have an aluminum tree behind your house.

I like the idea, it does look large and bulky though.

how much wiring is reqd for the tach?

anything under the hood?

is it powered by the boat batter, or internally?

Peak RPM memory?

whats the response time for the tach?

and of course, howmuch $$$?
 
#ZERO

#ZERO

Beach Bum
Location
Florida - U.S.A.
Interesting. :cool2:

Are you using an inductive pick-up for the tach and how fast is the sample rate going to be?

Also what are you go to do about a lanyard?

It does look like it's on the large side and those sharp corners look like an accident waiting to happen mounted on the bars IMHO.
 
sfab

sfab

X
Location
Canada, QC
its a tad longer than the OEM start/stop switch , from the handle bar to the top its 1 1/2", 3" long by 1 5/8". The power is taken from the battery, when the engine is off it shows 0 rpm for 30 sec and then shutoff (sleep). It consume approx. 150ma when running and 0.2ma when sleeping.

Theres 5 wires: 2 for the power, +12v and ground, a wire that must be joined to the magnetic pickup from the magneto, the start wire to the brown one and the stop wire to the white one.

The responce time aka sample rate is approx 1/4 of a second right now but i can adjust it to whatever i want.

since its a prototype, it does look bulky and square but every edges has been round to a radius of 1/8" to avoid accident. I might include a magnetic laynard if this thing has any market value.

right now the only function it sports is the gas comsumption approximation but might replaced it by a max RPM memory too. The resolution is 1 RPM.

as for the waterproof thing i might end up filling it with epoxy... lol

Price? Well if it reliable i might be able to sell it for around 120$

thank you all for the inputs!
 
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sfab

sfab

X
Location
Canada, QC
Kennay said:
With that fast of a rate, I'd buy one for 120 depending on the final product for sure
Click to expand...

thanks kennay!
im still unsure of what to do. it might end up as a tach if i cant make this thing waterproof. the price might drop too.

i did this thingie because my current start stop switch is dead... i will probably have the only one ever produced too! lol
 
crammit442

crammit442

makin' legs
Location
here
Kennay said:
For that much, it better come with a hidden robotic arm to also wipe my ass! :lmao:

Bet it works well though :naughty:
Click to expand...

It works VERY well. It has more features than you'll ever use and includes mounting hardware. Single wire inductive pickup and usable on nearly any 2 or 4 stroke motor.
 
Mouthfulloflake

Mouthfulloflake

ISJWTA member #2
Location
NW Arkansas
many people would pay a pretty $$$ for the magnetic lanyard feature ALONE...

you might want to explore that and see if you can still sell them at a decent price and make a buck...

youd sell LOTS of them.
 
steveyz250fpilot

steveyz250fpilot

Banned
Location
Huntsville, Alabama
Mouthfulloflake said:
many people would pay a pretty $$$ for the magnetic lanyard feature ALONE...

you might want to explore that and see if you can still sell them at a decent price and make a buck...

youd sell LOTS of them.
Click to expand...

If it was like the newer cars, that would be kick ASS! You don't have to attach a lanyard, but you have to have the "key" within like 5 feet of the ski!

SWEEEEET! I'd get one
 
GIL

GIL

Power In The Hands Of Few
Location
Cullman AL
crammit442 said:
It works VERY well. It has more features than you'll ever use and includes mounting hardware. Single wire inductive pickup and usable on nearly any 2 or 4 stroke motor.
Click to expand...


Will the m.f.er fix my broke flywheel??? If so, I'll take 76 of them. I'm sure they will come in handy for more broke crap.
 
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