Click here to return to the home page.
Morgan 3 Wheeler
Who's Online Now
9 members (RichardV6, cerealsurfer, bmgermany, britmog, Morganmike, Gordon D, TBM, Zach, IcePack), 305 guests, and 67 robots.
Key: Admin, Global Mod, Mod
Top Posters(30 Days)
+8Rich 75
Newest Members
Scot_SJI, Jimmers, Breen60, Davidmog, Stevecarr
9,596 Registered Users
Newest Topics
Are Octopus screwing ev owners
by John V6 - 01/09/26 04:50 PM
4/4 Suspension Install - is this normal?
by ScotiaSteve - 31/08/26 10:52 PM
Delay to bring up oil pressure ( 2006 +4 )
by Cerberas - 31/08/26 03:11 PM
Clarkson Review of Supersport 400
by Stephen888 - 31/08/26 01:09 PM
M3W Treffen Grindelwald 2026 /2
by Laurens - 31/08/26 01:03 PM
M3W Treffen Grindelwald 2026
by Laurens - 31/08/26 01:01 PM
Hood catches rear
by AndyGoff - 31/08/26 11:34 AM
Latest Photos
Wales
Wales
by Joske Vermeule, September 1
tow bar
tow bar
by G Walker, August 24
Prescott double anniversary
Prescott double anniversary
by CooperMan, August 18
Air Crash Sites: Cairngorms
Air Crash Sites: Cairngorms
by RedThree, August 13
Four-seater luggage rack
Four-seater luggage rack
by Soleng, August 9
Forum Statistics
Forums39
Topics49,861
Posts837,533
Members9,596
Most Online1,063
Jun 14th, 2026
Today's Birthdays
Jonny72
Previous Thread
Next Thread
Print Thread
Page 18 of 18 1 2 16 17 18
Joined: Jan 2014
Posts: 1,075
D
Has a lot to Say!
Offline
Has a lot to Say!
D
Joined: Jan 2014
Posts: 1,075
Originally Posted by LightSpeed
Originally Posted by rockabilly john
Just a couple of questions.
How much current does the starter switch draw?



The switch itself draws nothing, it is the starter that consumes electrical current.

If you have no way to measure current in the line coming from the starter I would recommend asking S&S technical staff to get a base line for starter current draw. With the clutch depressed then only the Centa is causing drag in the system thus raising current.



The starter is a Miata starter so I highly doubt that S&S can help in that. Most modern cars/bikes have a start switch that is used to trip a coil inside a starter relay. The relay coil as said above pulls hardly any load at all. The main power to the starter solenoid is usually direct wired with a fusible link in the line. The fusible link is designed to burnout like a fuse when there is too high of load in the starter etc. So your little start button on the center of the dash does NOT directly hook to the starter.

Most heavy load on a car's wiring system run through relays, horn, fuel pump, etc. They're also covered by fuses in the fuse panel, so everything pretty much is covered for you.


Dan
Joined: Feb 2019
Posts: 3,857
Likes: 2
Talk Morgan Addict
Offline
Talk Morgan Addict
Joined: Feb 2019
Posts: 3,857
Likes: 2
You are correct Dan, the relays and coils are doing the work.

I mentioned S&S because the starter for their big bore bikes would give an idea of the kind of power required to turn the big cylinders. Mazda is very different in energy to crank over their small engines.


2019 M3W Sold and is now in Las Vegas enjoying the showgirls :-)

Joined: Jul 2019
Posts: 5,442
Likes: 468
L
Charter Member
Offline
Charter Member
L
Joined: Jul 2019
Posts: 5,442
Likes: 468
I suspect few hobbyists will have a meter capable of measuring starter current draw, given the norm is to put an ammeter in series with the device drawing current.

As I suggested a rotor in a starter while stationary acts like a dead short UNTIL the magnetism in the motor builds up causing it to begin to rotate... thus a graph showing the rise in current at the instant the start sequence was initiated would be heading skyward... any average AVO (amps volts Ohms) meter connected in series expecting to read current would be toast..

I suspect the actual current draw would be variable for the reasons I suggested in my previous mail.. But I have been known to be mistaken and more than once.. (-:

There are other types of meter that can be clipped round starter cables and will give a reading though they tend to be specialist equipment..I suspect the initial inrush current could perhaps get to 600amps..as ever your results may vary..?

It can be very dangerous messing with high current devices, even in lower voltages, LARGE amounts of POWER can cause injury or worse..and plenty of power can be stored in a 12 volt battery, so be careful folks.

Page 18 of 18 1 2 16 17 18

Moderated by  TalkMorgan 

Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.5