Digital Carb Sync

[tz89]

I've designed and built a digital carb sync circuit board. The board is designed with the Valkyrie in mind and is easy to build. It attaches to an Arduino UNO microcomputer or compatible clone. Please post any comments or questions that will help me decide any next steps.

The first photo using a hot plate to neatly solder the sensors. The pads are big so a soldering iron works. 



A close up showing the hot plate results.



A close up of the soldering iron results.



A close up showing alignment of sensor notch with white dot on board.



Everything else is soldered on by hand using a soldering iron. The raw board.



The back of finished board before mounting the LCD screen.



The parts.



The board hand soldered with 6 sensors for a Valkyrie, with a removable LCD screen. It is mounted on the Arduino.



I built this for my own use but other people seem to want one. If interested please take this Google form survey to help me decide whether to make it available. http://goo.gl/forms/Oupfgt3SeK

I'm a newbie on this board so I hope it is ok to post this. I am shopping around in the NW for a nice used Valkyrie and have looked at a couple. I ride a Venture now and you can see the idea evolve from old auto parts at http://www.venturerider.org/forum/showthread.php?90191-New-digital-carb-sync-board

and http://www.venturerider.org/forum/showthread.php?73158-Built-a-digital-carb-sync

Thanks for any suggestion on how to make this thing useful.

[GiG]

Very impressive!
I thought the hot plate was a bit overkill and might damage the sensors, but I guess you had you reasons, mabey for alignment, but the results look great.
Yes, I may be interested, let us know how the testing goes.
Good job, tz!
CHEERS,
GiG

[tz89]

Thanks. I used the hot plate to experiment with that technique. It is easy and as you can see it turns in great looking results. I just figure some guys will be wary of surface mount soldering with a soldering iron. It doesn't have to get that hot but you have to monitor it and turn it off. What you see in the picture is the base unit of my slow cooker and so it doesn't go super hot like a real hot plate would (~450 degrees).

Testing has shown this works great. I usually set the software to readout in 1/10" of mercury. I've tried it set to 5/100" but imho that much accuracy is not needed. The sensors I use are quite good. This photo has the sensitivity set high.



The future RPM feature still needs work.

[Pappy!]

I like it!
We have a digital one at  the shop and it is great to use. Will be using it possibly tomorrow as I just did the carbs on my VMax today and will re-install tomorrow morning.
Ours shows as a simple bar graph and no numbers. The dampener is apparently in the electronics.

[Colin]

Excellent. Completed your survey. How soon can I have one?

[jimmytee]

Filled out your survey. I could be interested. I honestly have not synced my carbs myself. Synced my Carbs on a 750 Nighthawk many years ago and plan to rebuild the carbs on a project 86 Aspencade(4 cylinders). I have been thinking about re syncing  my Valkyrie carbs this winter. I already own a dual digital manometer I use in HVAC trade. I had figured I would just build a little manifold to sync my carbs using it. Looks cool though.

[robin]

Did survey

[Novavalker]

Survey completed.

[tz89]

I have one board and parts kit left over from my prototype run. As an experiment I've posted it on ebay.

Most forums discourage posting ebay links. You can search on digital carb sync or use the #s. Thanks.

 111530378990

 111530378389

[tz89]

Response to a couple of comments from the survey:

Yes - it does hook up and display all 6 carbs at once. There are 2 rows of 3 sensors and 2 rows of info on the display to match.

All the drill holes line up so it will be easy to mount in a case. I have not designed or built a case.

I am considering posting the software on an open source platform but have not committed to that yet.

Thanks again for the suggestions and questions.

[tz89]

FYI

The software has been published on GitHub in repository Digital_Carb_Sync_Shield.

The board files have been published, too.

[tz89]

Here's a picture of a small batch of the final board I just got. The main changes were to replace the voltage switch with a jumper, and evenly align the sensor pads so it looks better.

I have one guy doing a build that will help me field test the instructions. I'm still not sure what happens after that - in small quantities it is kinda spendy. I'm having fun with it, though.

[CajunRider]

Very cool!!!  And can be used for many different bikes!!

"Awesome sauce!" 

[tz89]

Some factoids you can help me chew over.

I posted info on my Venture forum and on this Valkyrie forum. Those are the two bikes I had in mind to benefit most during design although of course it would work on any multi carb engine (up to 6). There was generally favorable to enthusiastic response from those who posted.

My survey attracted 22 responses.

My Ebay no reserve auction of a board drew 3 watchers and no bidders. The parts kit did sell to someone who wanted to do a build and bought the kit for convenience.

Discussions with a Chinese manufacturer resulted in a cost per assembled board of $150 for small volumes and $61 for quantities of 1000 or more. I could probably sell a kit for that to do it yourself types but that's about it.

Now what?

I'm thinking that I'll build one more for my brother. I have 2 for me. I have a few more boards and parts kits without sensors. I might hang on to them or make some available to open source collaborators on GitHub. I would swap a board and parts for a nice case if someone has that capability. And I am open to more suggestions. Stay tuned!

[Jess Tolbirt]

i could see motorcycle shops needing those that work on old bikes,,but the general public i cant see..

[tz89]

I do have a few board and parts kits for forum members. Just send me a PM.

[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.

[dreamaker]

I got mine in to day, Man that was fast!!!!! Just glancing at the components, It didn't click in my head, on how to use it. But on the beginning on this thread, there were you have the series of pictures.  The very last picture made everything come together and make sense to me. That pic I don't believe came in the package you sent me. Waiting for the rest to come in and spring to check it out.

Thanks Again

[tz89]

Thanks for the feedback. I'll add more pictures onto the cd.

If the weather would improve here in Oregon I would do a fresh set.

[Art708]

The Venture has about the easiest carbs to sync that I ever tried.  I owned 2 Ventures and 1 Tour Deluxe. It seems that I had to synch them quiet often to keep it running properly. I have had 5 Valkyries and haven't synched any of them.

[tz89]

Here's a source for the sensors quoting a lower price...

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

There's an option for 5 minimum with increments of 1 - perfect for Valk builders.

That's $24 less than digikey. Pays to shop around.

http://www.digikey.com/product-detail/en/MPXV6115VC6U/MPXV6115VC6U-ND/951851

[tz89]

I just got a new batch of boards in the mail today. I'll be doing a 6 sensor build this weekend and will post a picture. If you want a board PM me.

[tz89]

I got a nice build out of my new batch of boards. I'll probably keep this one unless someone on this forum really wants a ready-made. PM me.

[BonS]

I gave my Digi Sync its first workout today. I had never synced a Valkyrie until today. On other bikes I've used both mercury filled and Carbtune sliding-steel-slug type manometers that are made for four cylinder engines. The digi-sync simply blew them away! The combination of it's small size, damped digital readout, and seeing all six cylinders at once is awesome. I loved not having to worry about sucking in some fluid and watching vibrating bouncing columns while I worked.

I started out by referencing the factory manual but soon abandoned it because it "assumes" that I only have a four-channel balancer. All I needed to know what that cylinder #3 is my nonadjustable reference cylinder and I was good to go. After watching the interaction between the different cylinders and the idle speed I'm convinced that there's no comparison between balancing all six cylinders at a time versus Micky-Mousing around with a four-channel balancer. I've already sold my Carbtune on ebay because there's no going back!

I simply laid the Digi Sync on the seat so that the display had the same orientation as the engine. No confusion at all. And when finished the Digi Sync simply packs up in a shoebox sized tub without worrying about spilling fluids. Love it!

[BonS]

After receiving several requests I'm going to build several of these for members here on our board. PM me for specifics if you're interested. No this isn't a business, I'd call it a service. I think you have to earn at least minimum wage before I'd call it a business. 

[dpcarson]

How much for just the box?  I just finished building my gauge last night.  Thanks Tom!!

[tz89]

BonS is planning to build complete units in a box (once I get a batch of boards made).

Dreamaker built a box for his that may be useful to you.

You should contact them.

Box building is outside my skill set, though I like to see people experimenting.

Meanwhile, congrats on your build. It shows even someone who self describes as having only a thimble full of electronics knowledge can do this.

[dpcarson]

Hey Tom.  I was asking Bon about the box.  I was saying thanks to you for sticking with me last night getting the thing built and working.

Got my hoses today and will be trying her out tonight over a few cold ones.

[tz89]

I suspected so, but didn't want to leave anyone hanging....

[Jess Tolbirt]

after he has a "few" cold ones he wont know if they worked or not LOL

[dpcarson]

Well I do not have my D screw tool yet.  Finger wrenches came in today but not the d socket.  I did go out and hook it all up to see what I could see.  What I found is that at idle all the cylinders were within 2.  But when I take the rpm's up to around 2500 cylinders 5 and 6 were about 8-10 higher than the other 4.  Other 4 were all within 2 or 3.  Any diagnosis on this?  Anybody that has done it at least once has a lot more experience than me.

Oh, and that was with a couple cold ones Jess.  When you can't see the screen you go back to wiping stuff down and polishing chrome.

[tz89]

The higher the number the more vacuum being measured. 8-10 is a lot of difference - about an inch of mercury in a old style mercury manometer.

[dpcarson]

Awesome.  Thanks!

[dpcarson]

Sorry, follow up question.  Will higher vacuum levels lead to leaner mixture or richer mixture?

[tz89]

Oh, you probably want the Valkyrie experts on here to give advice.

The general basics and I know you probably know this:

The point of a sync is so all cylinders are "breathing" at the same rate and not working against each other. It's about balance.

Generally, more vacuum doesn't mean richer or leaner. It just means that cylinder is drawing more because the engine is turning faster. The exception could be if the carb is jetted wrong or there is a problem with the jets (eg blocked).

What I think is noteworthy about your results is that 5&6 show similar results different from the others at higher RPMs. Maybe the throttle linkage is doing something it shouldn't or there is a blockage in the air flow (eg clogged filter).

[BonS]

Hey Tom.  I was asking Bon about the box.  I was saying thanks to you for sticking with me last night getting the thing built and working.

Got my hoses today and will be trying her out tonight over a few cold ones.

Here's the enclosure of my Gen2 Digi-Sync. It's a cleaner build but it's not exactly plug-n-play. The end result is worth it though. The enclosure is a Bud box and can be purchased from Mouser or Digi-Key easily but I don't recommend it unless you have considerable experience with electronics. It's not obvious why but trust me, choose another enclosure if you don't like doing brain surgery. For me? I do brain surgery (so to speak).

You may want to check out another thread about the Digi Sync started by Dreamaker. It calls out a box that's easier to work with. http://www.valkyrieforum.com/bbs/index.php/topic,74909.0.html

[henry 008]

I have a board "kit" that I bought off of tz89. It has the board some fittings and an instructional dvd. I have decided to have someone build a complete 1 for me, instead of doing it myself. if anyone is interested in purchasing my "kit", pm me and we can work something out.

[dpcarson]

Henry, you may want to give it a try.  I am extremely electronics illiterate and I actually got mine to work.  Only about the second or third thing I had ever soldered in my life.

[dpcarson]

No fancy case yet, but this does work well.  This was as close as I could get it to perfect at idle.



They all bounced back and forth between 198 and 200 but all 6 cylinders stayed between those numbers so I guess that is about as good as I can get it.

[tz89]

Actually that is perfect. To save display space there may be round off errors instead of decimal points.

If you are comfortable loading the software, I could send you software that displays to 5/100 inch of mercury accuracy. Silly, useless, fun.

Leave it alone. It's perfect.