FV and a Mychron5

[HB280ZT]

Is anyone running a Mychron5T or 2T on there Formula Vee. If so please let me know as my Mychron4 is acting up and I have sent it back to AIM and they tell me it is working fine. But I a still having issues with RPM and GPS. Have replaced the GPS and I still is not working correctly. The reason that I am asking is because AIM says that it will not work on a FV. Thanks for your help.

Harry
FV#77

[Stumpthumper]

There are an ever growing number of us running them in the Northeast. I just picked one up this off-season and ran it the first weekend...worked very well. The rpm is sketchy at idle (jumping all over the place) but once under way it works great. Gps works great too. Most, if not all, of us have it mounted on the dash.

Edit: also, you might want to pick up the 12v "evercharge" from kartmarter.com. it lets you connect your my hron to your battery so you don't need to keep recharging it...which would require removing battery which usually requires removing the MyChron from the dash...a total pain in my case. I bought a similar product from somewhere else and it didn't work.

[mikehinkle]

I have been using a Mychron 5 2T. I bought mine from kartsmarter.com. The owner is very helpful.

A couple of things to consider.
1. The Mychron 5 does not do oil pressure. You will need a Oil pressure gauge and dummy light in the car still as you can see in the picture.
2. The Mychron 5 has a battery unit on the back that is intended to be recharged before a weekend in kart racing. Do yourself a favor and buy the extra cable to hook it to the battery: https://kartsmarter.com/pages/ever-c...pter?nopreview
3. It is intended to be mounted on a steering wheel so mounting it on a flat dash is a trick. I used a threaded rod coupling to mount it to my dash in the BRD. In my protoform I just cut a big hole for the battery/wires.


Getting data from it is much easier then the older systems. You can connect with wifi, no physical cable required.

Also the shift lights can be set to predictive lap timing. This is what I use. Each of the 6 LED lights count as a 1/10th of a second. One light for each 10th you are under or over your best lap of the session. Instant feedback when you are trying new lines or when you are over driving a corner you will know on exit....

[HB280ZT]

Great information guys. Any issues or solutions with the RPM and GPS as that is what is causing me issues with the Mychron4 unit I currently have.

R/--
Harry
FV#77

[Stumpthumper]

Great information guys. Any issues or solutions with the RPM and GPS as that is what is causing me issues with the Mychron4 unit I currently have.

R/--
Harry
FV#77

I emailed you a couple thoughts, but since others may have issues with the RPM, make sure the pickup wire is not run in any conduit or tubing. It's odd, but it needs to be loose and routed clear from other electrical wires. Also, ensure it's not pinched anywhere. Mine was pinched at the firewall a little and it blocked the signal. I secured mine on the right side of the car along the throttle tube and use loose zipties to keep it in place. The rest of my electrics go down the left side.
I can't speak to the GPS, but I would try to borrow somone else's GPS antenna to ensure that's not the issue. Like Mike said above, Kartmsarter.com is hugely helpful and I have also had very useful help from calls with the technical department at Pegasus. Both seem to know more about the Mychrons than the people at AIM.

[FVRacer21]

Some electronic tachs need a filter when the car is running points. Does the Mychron run an inductive pickup or is it triggered off the coil?

ChrisZ

[Stumpthumper]

Some electronic tachs need a filter when the car is running points. Does the Mychron run an inductive pickup or is it triggered off the coil?

ChrisZ

It's inductive. Which needs the filter?

[Matt Clark]

I think both methods need the filter... if I remember right, simply having a coil is the deciding factor with the MyChron units.
that being said, I had issues with my MyChron3 (off the coil). their filter corrected it right away.

[Stumpthumper]

My RPM works great, as long as you are above 3k rpm. It jumps around a lot at idle.

[mark elder]

I have messed with lots of Mychron 5's. I think I have 6 on the fleet. Never ever had a rpm issue. Perfect at idle and all thru the rpm range.

The rpm wire simply picks up electrical energy from anywhere nearby (thats its problem). I wrap it around a plug lead just like you but...

the wire from the dash unit needs to run its own path away from any other wire (I run coil feed etc down the right hand side) and the rev wire down the left hand side all by itself.

and... I don't wrap it near the distributor (lots of energy and magnetic fields etc etc), I simply have the rpm wire pop into the lefthand side of the engine bay and it heads straight to the plug wire of #1 (and miles away from any other ignition lead).

No filter etc.

[mark elder]

Opps; and in your photo, the wire wraps around the spark lead a few turns then the wire loops around and touches the ignition wire a second time 2-3 inches away. Bad. Might be the whole problem.

[HB280ZT]

Guys thanks for the great information. One question that I have is what type of wire, size, etc are you using for the RPM pickup and how did you get the plastic piece to work on the larger wires? I am running the Taylor 8mm wires and the plastic wire retainer does not fit at all. Again thanks for the help.

R/--
Harry
FV77

[Stumpthumper]

Guys thanks for the great information. One question that I have is what type of wire, size, etc are you using for the RPM pickup and how did you get the plastic piece to work on the larger wires? I am running the Taylor 8mm wires and the plastic wire retainer does not fit at all. Again thanks for the help.

R/--
Harry
FV77

I am running 16ga.
My plug wires are thick, but I was able to press on the clip with a but of force.

[mikehinkle]

You dont have to use the clip at all. I dont use it I just loop the wire around a few times and zip tie it back to the wire coming from the cockpit.

[nhJohn]

We used MyChron's in karting for years …. however the first thing I noticed was that you are all picking up the signal next to the distributor cap. We always put the pickup right against the rubber boot on the plug. Anyone try that?
John

[mark elder]

yip, always. The wire needs to be within 2-3 inches of the spark plug (which puts it furthest from other bad stuff; other leads and wires etc).

[Keith Lawrence]

Old thread, but anyone try an Alfano 6? It's about the same and has both temp and pressure senders that can be used for oil. Seems like a great and inexpensive option.

[E1pix]

Not much help Keith, and long enough ago I can’t recall the model (not a 6), but we had an Alfano on our last kart and loved it.

Tech always changes of course, but mostly I wanted to say we used it over close to 100 days and probably 6-8,000 miles (US development team for a then-new, Swiss motor), and never once had any issue whatsoever. Company support was good, too but again, quite a few years ago.

[Stumpthumper]

Old thread, but anyone try an Alfano 6? It's about the same and has both temp and pressure senders that can be used for oil. Seems like a great and inexpensive option.

Had I not just bought a Mychron5, I would get the Alfano and give it a go. I mostly use TrackAttack for data analysis so either would work for me. I like the idea of getting oil pressure too if it does that, though it looks like all the sensors are sold separately.

[DanW]

I used about 10 turns on the gray wire around the plug wire. They need that many because the signal from a magneto two stroke is a hotter spark.

[fvee62]

Also, I had been told that the temp sensor would not work for oil. Hooked it up anyway and it reads oil temp with no problem.

[Stumpthumper]

Also, I had been told that the temp sensor would not work for oil. Hooked it up anyway and it reads oil temp with no problem.

Same here. It works just fine.

[problemchild]

Same here. It works just fine.

It may run out of scale about the time that knowing your OT is critical. Very few data systems will scale WT to go to 300F which would be common upper range for OT.

[Stumpthumper]

It may run out of scale about the time that knowing your OT is critical. Very few data systems will scale WT to go to 300F which would be common upper range for OT.

Over 250-260 is considered bad, so there's no need to go to 300. And you can choose either a thermocouple or a thermosresistor if you have a preference. I find the set up works very well.

[Keith Lawrence]

Stumpthumper,

Can you provide the specific OT sensor that you are using?
I'm not sure of the difference between the two types that you referenced.

Thanks.
Keith

[problemchild]

Over 250-260 is considered bad, so there's no need to go to 300. And you can choose either a thermocouple or a thermosresistor if you have a preference. I find the set up works very well.

Over 300 is bad.
Over 280 is not good.
Over 260 is high alert, only a few laps left in the race.
Over 240 is must be a warm day on a tight track with lots of 3rd gear
Over 220 is perfect.
Please believe that the fast guys running in a power draft in a good pack, are dealing with higher than ideal oil temps

If I'm leading a race with 2 laps to go, and oil temp is 270, I'm not stopping.
If I'm leading the Runoffs with 2 laps to go. and oil temp is 290, I'm not stopping.
If I'm leading the Runoffs with 10 laps to go, and oil temp is 300. I'm stopping.

Perhaps some don't want to know if over 250, but I would prefer to have that info.
Having said that, although not ideal, it would be much better than nothing.
I would add an external gauge if that was my only option..

[ajpastore]

Looking at the Aim sensor, I've never felt confident the probe would stick far enough into the case to reflect oil temp as opposed to the saturated engine case temp. Probably an unfounded concern so don't quote me- but that's why I use the standard sensors we've used for ever, and came up with the curve to use them. They are also much less expensive.

As Greg states, being in a hard fought battle, in the draft will definitely produce higher temps. So you should always try to run out front

You can see the difference lap to lap, hotter when following, cooler when in clean air. I've seen the temp drop just by pulling out of the draft down a straight.

-Andy

[nhJohn]

Looking at the Aim sensor, I've never felt confident the probe would stick far enough into the case to reflect oil temp as opposed to the saturated engine case temp. Probably an unfounded concern so don't quote me- but that's why I use the standard sensors we've used for ever, and came up with the curve to use them. They are also much less expensive.

As Greg states, being in a hard fought battle, in the draft will definitely produce higher temps. So you should always try to run out front

You can see the difference lap to lap, hotter when following, cooler when in clean air. I've seen the temp drop just by pulling out of the draft down a straight.

-Andy

So, if you run with an engine temperature in the 180 to 210 range, is that okay?
Too cold?

[ajpastore]

So, if you run with an engine temperature in the 180 to 210 range, is that okay?
Too cold?

John, If your asking me, I would say I don't know, ask your engine builder!

But in my brief history of FV, three different cars with multiple cooling schemes, the only time I've seen oil temps that low in a full race session, are cold, rainy and slow races. My temperatures follow closely to what Greg published.

Andy

[Stumpthumper]

Stumpthumper,

Can you provide the specific OT sensor that you are using?
I'm not sure of the difference between the two types that you referenced.

Thanks.
Keith

So the thermocouple is the yellow (k-type/2 wire) sensor. Basically the fluid temp generates a voltage depending on the temp and the logger reads that voltage. Looks like this:
https://www.pegasusautoracing.com/pr...asp?RecID=5112

The thermoresistor has a 3 wire cable and sends a voltage to the sensor and the sensor then acts as a resistor and the logger reads the resultant voltage. Looks like this:
https://www.pegasusautoracing.com/pr...asp?RecID=7263

I have ordered 2 mychron5s with the water temp sensor, and one came with the black sensor (normal) and one came with the yellow one (an anomoly I believe). Both work fine, but if you need an extension cable you'll need to get the right one (yellow/black). Pegasus tech support is awesome with helping on this stuff.

I then head to my local Napa and get a thread adapter to fit the sensor to my existing oil temp hole.

_Dave

Andy, I've found the Mychron temps mirror the old analog gauge temps I saw and my sensor was tucked inside the adapter a little bit. Others mileage my differ, but all seems good to me.

[Keith Lawrence]

Haven't seen these available in the US but would be great addition for a FV.

Alfano 6 Oil Pressure Sensor at an Australian website
https://www.alfano.com.au/product/oil-pressure-sensor/

[Stumpthumper]

Haven't seen these available in the US but would be great addition for a FV.

Alfano 6 Oil Pressure Sensor at an Australian website
https://www.alfano.com.au/product/oil-pressure-sensor/

Agreed. These systems looks really good for vee.