Motorcycle starter motors – any general workshop uses?

[Robin GrahamParticipant @robingraham42208]

I’ve recently been invited to join the Amazon Vine program which, if you don’t know, permits members to order stuff from a limited selection of products free of charge in exchange for a review.  Mostly it’s a pain, 300 pages of stuff I really don’t want even for free (‘butt lifting’ knickers for God’s sake!) but there are several offers of motorcycle starter motors which look as if they might be useful for some (as yet hardly imagined) purpose. For example https://www.amazon.co.uk/dp/B0DWX9QB8B .

Unfortunately there is scant technical info in the product listing – it’s 12V and has ‘ultra high rotation speed’. But what does that mean?

A potential use for me might be as a motor to drive a mill table feed, but obviously it would have to be adaptable to run at variable speed.

I’m really just trawling for info about this type of motor and what they might be useful for, apart from starting motorcycles.  Any info will be appreciated!

Robin.

[Howard LewisParticipant @howardlewis46836]

As a starter motor, I would expect it to draw a heavy current.

The “high speed” suggests that it might be intended to be geared down, which will reduce the current draw.

If so, to produce the sort of speeds that we would use in our workshops, for either powering a small lathe, or providing a power feed,(Other than ultra high speed engraving) would require very high ratio step down gearing.

If you could find the machine on which they were originally used, this might allow you to find more details about motor type and characteristics; possibly even mounting arrangements.

[DiogenesParticipant @diogenes]

It’s a ‘standard’ 12v brush-motor – the ‘high speed’ claim is likely to be because ‘high-cranking-speed’ is one of those benefits wily salesmen always claim for both batteries and starters..

– the fitment details list a number of what look to be Yamaha models / clones – (to me) it looks very similar (identical?) to the much-copied & globally ubiquitous ‘XV535 Virago’ model if you want an easily-found yardstick.

 

 

 

 

[not done it yetParticipant @notdoneityet]

THINK COOLING!  Starter motors are designed for short term high power delivery.

[DiogenesParticipant @diogenes]

I agree.

The advert says it increases horsepower so maybe worth getting a couple and putting them in the back of the car, you won’t need to press the accelerator so hard and will thereby save some petrol.

[Michael GilliganParticipant @michaelgilligan61133]

The company’s ‘mission statement’ seems simple and open enough

https://goofitparts.com/pages/about-us

So the basic review would surely be “is this a satisfactory pattern part ?”

But if Robin is more  interested in the “make from” possibilities, then some bench-tests would be a good start [sorry for the inevitable pun]

Q1. How much current does it draw at stall ?

… etc.

MichaelG.

[John HaineParticipant @johnhaine32865]

I think these may be series wound to give highest torque at zero speed as needed for engine starting. If so they would be totally unsuitable for our normal usage. It’s not as if motors are not easily available, I think they make even more motors than mobile phones!

[noel shelleyParticipant @noelshelley55608]

It’s intended use tells you all you need to know – high current drew, high torque, possibly by gearing, short duty cycle, why are copies of the original been made ? Poor quality or poor design so they fail after a short while.

Only this morning a news item on Amazon and it’s fake reviews !

I would have nothing to do with it ! Noel.

[JasonBModerator @jasonb]

I wonder how you could even do a review without using it for it’s intended purpose?

[Robin GrahamParticipant @robingraham42208]

Thanks for replies.  The consensus seems to be that that this sort of motor is unlikely to be of any general workshop use – I suspected as much, but wanted opinions from people more learned in these things than me.

I passed on the offer.

Since then I’ve  been offered a free windscreen wiper motor.  On the basis of a dim recollection of someone somewhere (MEW?) using one to drive a mill table I went for it and it does look as if it might be useful.  I just have to figure out the wiring! Four connections + chassis I guess. I’ve figured out two (high/low speed 12V wrt  ‘ground’ ), the other two must be used to ‘park’ the wipers.  Doubtless google and experimentation will reveal all in time.

JasonB – I take your point.  I am certainly conflicted about this whole thing.  The T&C’s require me to review only 60% of the stuff I receive, but it does seem somehow immoral to take something without giving anything substantial back.  In my defence I don’t always use things I buy from Amazon for the advertised purpose, but  when I review them I tend to go into tedious, mind-numbing detail about my application – and sometimes I get positive feedback for doing that!  Maybe that’s why I got invited onto the Vine program. Who knows how ‘The Algorithm’ works!

Pax nobiscum, Robin.

[SillyOldDufferModerator @sillyoldduffer]

The advert has no technical detail, not even obvious it’s a replacement starter motor for certain Yamaha motor bikes.  I don’t think it can can be sensibly reviewed unless it’s fitted to a bike.

Starter motors are designed to deliver a lot of power and torque in short bursts.   They have to crank a heavy engine up from cold and spin it steadily until the fuel ignites and the engine runs on it’s own.   Typically less than 5 seconds unless something is wrong.

One of the alternative motors offered has more information: power output = 1.4kW and 12A at 12V.  On the face of it, 12V x 12A = 144W, not 1.4kW!  However, I think the numbers are a simplification.  The motor draws about 120A when the starter button is first pressed and then outputs 1.4kW to accelerate the engine quickly up to cranking speed.  Once the engine is turning fast enough, the starter motor drops to about 12A, sufficient to keep the engine turning until the fuel fires.

I can’t think of an obvious workshop application for a starter motor – they are too specialised!    What tool needs a motor delivering 1.4kW for a few seconds, idles at 144W for several more, and then needs a long rest to cool down?  A punch maybe?   Dunno.

The power supply is another complication – hard to find a mains power supply that can deliver 100A without spending big money!  Powering a starter motor on a bike isn’t a problem because vehicle batteries are designed to deliver lots of amps in short bursts.  Powering it in a workshop is a problem to be solved.

Windscreen wiper motors are much more useful.  They run from an ordinary supply with enough continuous power to wind tables, lift heads, and maybe drive a small reciprocating saw etc.  But these days, they might not be top choice because new steppers and brushless motors are competitively priced.  Rather than mess about adapting a surplus motor, buy one of the correct specification with a controller and power supply.  Whichever is easiest.

Dave

 

[John HaineParticipant @johnhaine32865]

I can’t understand the enthusiasm for re-purposing w/s wiper motors.  30 years ago perhaps before electric motors were so cheap and general purpose but today there are so many types of motor at sensible prices and relatively standard mounts it makes much more sense to use a new motor, DC or stepper depending on application.

 

[jamesp1Participant @jamesp1]

Those starter motors are perfect for if you have an IC engine that needs cranking over to get it started, and not much else. If you run them continuously, they melt down. So not really much use in the workshop for driving leadscrews etc. As has been said, these days there are so many good purpose-built stepper motors and geared DC motors designed for automation use etc available it is not worth cobbling up unsuitable motors to do a second rate job. But if you do come across a windscreen wiper motor for free or close to, they do work for driving leadscrews etc.

[John HaineParticipant @johnhaine32865]

OTOH alternators from both cars and motorcycles can be repurposed as “brushless” DC motors.  Quotes because they still used the field winding brushes to feed DC to the rotor to generate a field to interact with an alternating 3-phase field generated by the stator windings.  There used to be a gent at the ME exhibitions who demonstrated a system for doing this, IIRC for electric loco drives.  He designed the system himself, basically a chopper-type 3 phase supply with the alternator acting as an “inrunner” type motor.  Fascinating to speak to but I once followed up by sending him the data sheets on the Allegro Microsystems brushless drive chips, and he replied to say that he hadn’t realised that such things already existed and seemed very demotivated. I felt rather guilty.

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