Who' Interested? Cheap alternator replacement.

What do you think?

  • ?40 for an alternator plus ?50 for a conversion kit !!!! I'll scrap the bike!

    Votes: 0 0.0%

  • Total voters
    7
Joined
Mar 31, 2012
Messages
36
Location
Wales (UK)
Hi guys,

As most of you know, UK ST owners have a problem with seized alternators due to poor rear wheel arch design and salt on our roads.

My alternator seized and I needed to replace it.

I take offence at having to pay ?350 second hand or almost ?500 for a new alternator which is basically the same as lots of other cheaper alternators except the high failure rate due to seized alternators pushes the price to unreasonable levels.

I have almost completed my prototype for fitting a ?40 second hand alternator to my ST1100 and I am fairly sure it will be a success.

Would anyone be interested in purchasing my modification if I were to have it mass produced?

The job involes fitting a converter plate to your engine and some filing.

I intend to have the converter plates produced by a local sheet metal company and I will include video and written instructions detailing everything you need to do to make an alternator that sells on eBay for ?40 fit your ST1100.

You would receive :-
The converter plate
Two replacement mounting bolts
Spacer washers
Written instructions
Link to a video of me assembling and installing the cheap alternator

To give you an idea of what you will need to do, you will need to purchase an alternator (I will provide details of which one)
Separate the halves of your new alternator and your old one.
Install the shaft / armature from your old alternator into the replacement one
File a few millimetres from the housing of your replacement alternator
Dremmel or carefully grind the front of the replacement alternator's housing
Remove and refit the brushes
Assemble the alternator within the frame of your bike

If you feel you are capable of these procedures then you can buy a cheap alternator rather than pay big money for either a new alternator or a second hand one which has been subjected to the same poor wheel arch design of your ST1100 and consequently will eventually fail again.

I have invested a great deal of time into this solution and the cost of having the converter plates produced will initially be quite high. This is basically due to the tooling process and a small manufacture run.
I estimate that I will be able to sell all of the parts you need (except the replacement alternator) plus a video and written instruction for around ?50 including postage in the UK.

Ok, so who's interested, and would you buy my solution for ?50 when your alternator fails?
 

John OoSTerhuis

Life Is Good!
Joined
May 10, 2005
Messages
5,222
Location
Bettendorf, Iowa
Bike
1991 SSMST1100
STOC #
1058
Simon, I'm sure your USA/CAN brethren with aging (or FAILED) 28 ampers would be very interested. You might want to also query ST-Riders.net and MY-Mc.com where there are lots of other ST1100 folks.

BeST of luck with this endeavor!

John [Keeper of the STOC loaner 40amp alternator upgrade tool kit]
 
OP
OP
Joined
Mar 31, 2012
Messages
36
Location
Wales (UK)
Simon, I'm sure your USA/CAN brethren with aging (or FAILED) 28 ampers would be very interested. You might want to also query ST-Riders.net and MY-Mc.com where there are lots of other ST1100 folks.

BeST of luck with this endeavor!

John [Keeper of the STOC loaner 40amp alternator upgrade tool kit]
I didn't think of that - got some meetings with some manufactureres this week - keep your fingers crossed for me :)
 
Joined
Dec 27, 2011
Messages
262
Age
68
Location
Kells Meath Ireland
Bike
ST1100
Good stuff Simon,let us know end result.you should also advertise it on ebay.There,s a fella on there selling drawings of how to make your own motorbike lift.
Pat
 
OP
OP
Joined
Mar 31, 2012
Messages
36
Location
Wales (UK)
I have just come home from a meeting with a fabrication company and it was very encouraging indeed.

I will be working on an in-depth explanatn of the process involved over the next couple of days. When I get my prototype back from the fabricators I'll take some pics and maybe share some more info.

I don't want to get too carried away and make too many promises before I am 100% sure that everything works as it should.

Watch this space.
 
OP
OP
Joined
Mar 31, 2012
Messages
36
Location
Wales (UK)
All is good, I have finally jumped over all the hurdles and got the Bandit alternator to fit.
It involves some special bolts, an adaptor plate and some Dremel work. It's actually an easy job to do once you have all the parts and should take less than an afternoon.
I'll be selling a conversion kit containing everything you need in the next couple of weeks - keep an eye on eBay. Detailed instructions will be included.
The one thing to note is that you need to use the shaft from your ST alternator. This is ok because in the case of the seized alternator syndrome it is only the case that gets damaged.
 

John OoSTerhuis

Life Is Good!
Joined
May 10, 2005
Messages
5,222
Location
Bettendorf, Iowa
Bike
1991 SSMST1100
STOC #
1058
So, Simon... if one had a failed 28amper, in order to use the Bandit alt and your kit, we'd have to also buy the OEM 40amper parts that connect the Honda 40amper alt itself to the engine-case/flywheel, correct? The shaft, bearing, base and O-ring, harness, and bolts come to mind. IOW, a *partial* 40amp alt upgrade.



BTW, what's the rated output of the Bandit alt?
 
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OP
OP
Joined
Mar 31, 2012
Messages
36
Location
Wales (UK)
John, this kit is not really anything to do with a 28a upgrade as its fairly pointless since you need to have a 40a shaft.
It is more a solution to the seized alternator syndrome we get here in the UK rather than an upgrade from the 28a.
 
OP
OP
Joined
Mar 31, 2012
Messages
36
Location
Wales (UK)
In answer to your question John, it seems that although I have been feeling smug with myself I have made one assumption too many :(
I have just had a quick Google and it seems that Bandit alternator only pushes out around 400w which equates to around 33A.
Doing a quick head count of current drawing items on my bike I still believe that this is enough juice, but it is a backward step.
Hey, I'm saving ?300 and the bike has lost about 7 amps of alternator output, and as long as the bike is happy with 33 amps then those extra 7 amps were surplus anyway ;) I am a musician too, and take it from me, amps are heavy !! :D
I'll have to do some measurements when the weather gets a bit better as all these figures are only theoretical until I have actual measured values.
It seems that our American cousins are very enthusiastic about upgrading from a 28a to a 40a. Why is that?
I am sure that Honda would not have let bikes out of the factory with insufficiently powered alternators when they had 28a units. Is it that the 28a alternators are running near maximum capacity for such a high percentage of the time, or is it that it won't support enough farkles?
 

John OoSTerhuis

Life Is Good!
Joined
May 10, 2005
Messages
5,222
Location
Bettendorf, Iowa
Bike
1991 SSMST1100
STOC #
1058
Why do we colonials like to upgrade...? --

more power for electrical farkles, and reliability. We don't have the 40amper corrosion issues UK ST1100 riders seem to have. As to power, starting the ST up in the morning (no overnight charger) and then getting caught in stop-n-go traffic on a hot day so the fan's running, and the brake lights are on -- your 28amper's probably not keeping up with demand/battery's discharging. Throw in some corrosion/resistance/heat to exacerbate the issue and your charging system ages quickly.
 
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