New digital carb sync board

[tz89]

I do have a few board and parts kits for members. Send me a PM.

[Flyinfool]

I wonder what you could save by using an android APP to eliminate the display and display driver and processor from your board.

Most of us have half of that hardware in our pocket already.

If I did not already have a carb tune I would have snagged one of your kits.

I love techno toys. I can do hardware but my programing ability flat sucks.

[tz89]

Thanks. It's designed to take that next step so the display can be eliminated. I've plugged it into a bluetooth enabled mcu and linked it to my phone. But I need to do a lot of programming to add function and style. The cost driver is the sensors. The 2-line display is only about $10 more or less.

[tz89]

I've been asked if I will build one. I don't really want to get into that kind of piece work. But if someone really wants to avoid soldering, I could do a couple of all-in-one with the board, the computer loaded with software and pre-tested. It would take a bit longer. PM me.

[syscrusher]

Alright, I finally took the time and put my kit together.

It wasn't too bad even with the fairly blunt soldering iron that I used.

The sensors must be pretty forgiving since I confused myself about notches and dots and installed the first one correctly first and then decided that I hadn't. I heated the leads and lifted it one side at a time, flipped it around and soldered it back down. I looked it over some more and then realized that it was right the first time and so I reversed the process again. It works perfectly now. I would really suggest that one just make sure the side marked with "K1252" is toward the pads marked with "Vin", "Vout", etc. The notch then lines up with the dot for all that I have seen but it's easy to spot the "K1252". The reason I got confused is that the manufacturing process makes a small dot looking indent on several corners of the sensors and they are easier to see than the notch. Oh well.

 

It was fun finding ways to hold parts steady while they were being soldered but not to difficult overall. I used a crappy 15W Radio Shack special soldering iron but I used very fine solder and kept the tip wiped with a damp cloth. Don't use one of those pistol type soldering irons because they make too much heat. You don't need much heat. Tom's notes on assembly are spot-on. The only thing I would add is that the other side of the sensor, the leads that are not "Vin", etc., are unused. My advice is to get a small glob of solder on the tip of your iron, use a finger to hold the sensor positioned correctly on the pads and then just heat one of the unused leads until some solder transfers onto it's lead and pad. This won't make an acceptable joint but it will tack the sensor in place so it doesn't move around when you solder the other pads. Take the heat away and start soldering the rest of the pads correctly, adding solder as you heat the pads. Then go back and do the first one the right way too. Have some de-soldering braid handy in case you glob too much on somewhere.

 

When I was done with fabbing it I loaded the Arduino drivers on my PC and then transfered Tom's binary to it. For a while I thought I had messed things up because I didn't see any characters on the display. I did some testing of just the Arduino to make sure it worked and it did. I then realized that the display was over-driven and so I then adjusted the pot and numbers came into focus. I must have soldered properly because the sensors all read the same value. I'm not completely sure which number corresponds to which sensor yet but it'll be easy enough to sort out.

 

Here's some photos of mine and a few of the steps in assembly. You'll see one with a tweezer holding some connectors and another with the tweezer holding down one end of the LED display and my finger on the other end getting ready to tack solder the first few pins. It'll be warm this weekend and I intend to use this then.

 

 

Edited January 16, 2015 by syscrusher

[tz89]

Thanks. Your build looks good.

 

I like the idea of tacking down the sensors with crude soldering of the non-functional side. I'll update the directions. Of course, using solder paste for the sensors is even easier.

 

The pattern of the numbers lines up with the pattern of the sensors. On your build you have two rows of two, left to right, top to bottom. On Valkyrie builds one would have two rows of three.

[syscrusher]

Thanks. Your build looks good.

 

 

I do the best I can with what I have. Thanks!

[KB2RWW]

I have not been on in quite a while here on the site but today I was pleased to see other riders like me that are involved electronics. I love the build and discussion that is going on here and can offer my services to anyone needing boards assembled and tested. further more After looking over the code and schematics that I believe it can be moved to a single board application using smaller discrete components and processor. It's possible to get this down to the size of a flip phone excluding the sensors and tubing. willing to help any way I can. looking forward to a great riding year this year.

[tz89]

Great. The more the merrier. That's what the open source project on GitHub is for.

 

The two big opportunities imho are the cost of the sensors and getting the RPM feature to work well.

 

These sensors are about $15 each unless you buy a lot. You can order automotive MAP sensors for very cheap but what I haven't been able to find is the spec sheet. They are sold by car year and model. I need to know the range of the vacuum they can handle, and the accuracy. If any one on here is an expert jump in. There must be a way to benefit from the mass production of automotive MAP sensors on a project like this and still keep things small and neat.

 

I've been able to use a non latching Hall sensor to read the RPM off a plug wire but it could use some electronic expertise to make that more reliable and stable. The signal source is the very definition of noisy.

 

Size is mostly determined by the sensors and display solution. Cost is driven by the sensors.

 

Everything else is pretty cheap and easy and as you say could be made a lot smaller.

[videoarizona]

Saving my pennies. Even though KIC offered to help me tune my carbs....I sure would like one of these anyway. Want to meet KIC...so maybe a carb tune day in Tucson is coming up as the weather warms....

[syscrusher]

It was a nice day in Omaha today so I went for a ride.

I got the motorcycle warmed up nicely and then I hooked up my new digital carb sync and got them balanced.

The difference between the left side and the right side was greater than the difference between cylinders on either side.

It seems to run smoother, maybe even more responsive and quicker.

With this digital device it is possible to get the carbs very balanced.

Take a look at the attached photo.

 

There was only one surprise really and that was when I removed each vacuum cap the motor stumbled on all except for the right side rear cylinder. On that one it didn't seem to matter if it had vacuum or not at least as far as how the motor ran. Does that indicate anything I should look at?

 

 

[Flyinfool]

Possibly a partly plugged vacuum port on that cylinder?

 

And if it is partly plugged, WHY is it partly plugged?

[tz89]

I would say that it is likely #3 isn't firing at idle. There are several threads on that. Possibly a plugged pilot jet.

[tz89]

Here's a source for the sensors quoting a lower price. The catch is that there is a minimum quantity of 5 with increments of 1. If you are inclined to build for all 6 so you can sync a Valkyrie you save $4 each - $24 less than at Digikey. It pays to shop around.

 

https://www.verical.com/pd/freescale-pressure-sensor-mpxv6115vc6u-253910

 

 

MPXV6115VC6U Freescale Semiconductor | MPXV6115VC6U-ND | DigiKey

[syscrusher]

If two people pooled resources each would pay $44 instead of $60 (for four).

That's a good find.

[videoarizona]

TZ,

 

I'm saving my pennies....do want one of your units.

 

FYI....

[tz89]

I got a new batch of boards in the mail today. I'll be doing a build this weekend. If you want a board PM me.

 

[syscrusher]

I'm not sure why Tom didn't mention it but I'll assume he'll do the same as he did for me.

You'll get the board and some instructions for how to place components.

Tom has a list of parts and part numbers if you source them from Digi-Key.

The LCD he used comes from Adafruit. You can get an Arduino Uno R3 clone from here for $8.50.

Tom sent the compiled executable for the Arduino so you just load the windows drivers for it and transfer the executable to it.

The hardest part was finding the vacuum lines for the connections.

A tip there is to find some vinyl that fits the sensors tightly and cut just enough to slip over the orifice barrels.

That will make the barrels of the orifices just a little larger so that the 1/8" vacuum hose fits them well.

I used needle-nosed pliers to stretch the vinyl that I found at Ace Hdwr so it would fit over the barrels.

You'll need to find way to couple the 1/8" hose to the larger size for the nipples on the Venture.

You can try to find conversion couplers or make your own by finding sizes of vinyl hose that slip inside of each other.

If you can get 1/4" or so to slide in it will provide an air tight splice. Do this multiple times till you match the size required.

 

Have fun!

[tz89]

Thanks. This is good feedback. I send a cd with all the instructions etc. There is a bill of materials that can just be uploaded to digikey. I include other good sources as I find them. I especially encourage buying a clone Arduino - that will save a bunch. I recently posted another source for the sensors. You can find the LCD cheaper but not by enough to wonder if it will fit and work the same, imho.

 

I use 1/8" vinyl tubing to connect to the sensors. It's cheap and easy to find at any hardware store. I use a longer piece of 3/16" tubing to connect to the bike. And I use a reducing connector between the tubes. Some hardware, some aquarium, and some gardening/irrigation carry them. I'm still looking for the perfect online cheap source, but have decided I should just offer what I have on hand as an option to board buyers from this forum. It adds a few bucks but saves driving around and/or shipping costs.

[tz89]

Got a nice build out of my new batch of boards.

 

[videoarizona]

Shoot...I should have asked you to build one for me!!

That looks great!!

 

My board and CD came in fine shape. Thanks!

Got a project to do for work (not completely retired yet)...but soon as we are done I'll start scrounging for parts.

david

[tz89]

Speaking of looking great, here's a home built enclosure project from someone using my board as the starting point. Those Valkyrie guys are getting after this!

 

There is something good about building your own tools. I got that from my dad I guess. He was partner and mechanic in an International tractor dealership.

 

 

 

Here's a link to that thread...

Digital sync tool

[Flyinfool]

Is there a feature for calibrating the sensors?

I noticed on the one above and in some other pics that they are all slightly different readings not hooked up. or is that just an at rest thing and they will all read the same when hooked to a single vacuum source?

[tz89]

Warning - math nerd alert.

 

To keep the display compact it uses whole integers not floating point numbers with a decimal point.

 

If all sensors are displaying the same that means there are no rounding adjustments in the math (and someone did a really good job soldering it all together).

 

The sensors return a voltage from about 0.5 to 4.5 volts. The Arduino translates that voltage range into a digital value 0-1023. The software I wrote maps that range into a different range for convenience - in the current version that is 1-337. There might be a round off depending on where it maps and whether the returned values are evenly divisible during calibation.

 

During start up the board displays the calibration adjustments. On the board I just built those are now showing all zeros, so I know there is just a round off in the display. But at first it showed some calibration happening to a couple of the sensors which I was able to correct with a little adjustment to the soldering.

 

For the hardcore the software is posted on GitHub, so you can turn off calibration and make other adjustments pretty easily. But for most everyone, including me with my own bike, I keep it simple. The sensors are more accurate than needed, and way more accurate than the manual screw adjustments on most bikes.

 

So...... it is normal for them to display within a point of each other with the bike off (or hooked up to the same vacuum source).

 

Hope that covers it. Let me know.

 

PS

 

When I saw the numbers from the Valkyrie photo I contacted him to see if he needed help. He replied:

 

These vary depending on whether it's a cold start up or if the unit has been sitting powered up for a while.

 

The resulting pressure values are:

27 27 27

26 26 26

These values may drift by a digit or two after a while but a reset brings them back together again.

I figured that's what the reset button is for.

 

The picture in my post was after a cold start and it sat for a while without a reset. I didn't notice that it had drifted until I looked at my post a bit later.

 

Those numbers are fine. Drifting could mean something is effecting the pressure in the tubes (maybe in the carb bodies as they sit). He is up in northern Wisconsin or Michigan - so everything may be warming up or cooling off as he works on it. But, it is important not to calibrate while the bike is running or you will get numbers that are off. If you trigger the reset or flash the power you will be off.

Edited February 18, 2015 by tz89

[tz89]

A pretty happy report from a Valkyrie guy. I'm glad I designed for 6.

 

Digital Carb Sync