GL 1200 alternator convertion - a somewhat different approach


Information and questions on GL1200 Goldwings (1984-1987)
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ndonev
Posts: 5
Joined: Mon Jul 06, 2015 4:48 pm
Location: Bad Honnef, NRW
Motorcycle: 1985 GL1200A Aspencade

GL 1200 alternator convertion - a somewhat different approach

Postby ndonev » Tue Aug 25, 2015 4:29 pm



As the title suggests, I also have the problem with the alternator on my wing. I have had her for less than 2 weeks and about 3k km before the alternator went dead. Completely. 0 volts on all the phases and all 3 wires show shortcut to ground. The regulator is also dead. Good thing was, it happened at the end of a 2k km trip and not somewhere in the middle. The next good thing was, I found out about the poorboy conversion kit. Found only the complete kit on ebay and did not like the price for it. I had to pay shipping and taxes on top of the price. Ok, I could do it myself. Not that I am so skilled or have all the tools, but I have done some fun projects and building something similar was not a very big deal. The only point I disliked was the necessity to move the radiator about an inch forward. My wing has a bug spoiler and I really like the look of her with it more. The radiator also has an about 2 cm (1") wide chrome or stainless steel frame added which partially covers the side spoilers and should be removed if I move the radiator forward, as it would not look so good with a gap of about an inch on the lower end. So I started to think how to do it. There is enough space for the pulley and the belt without moving the radiator... but there would be no space for the fan. OK, I'll worry about that later. I needed a pulley and a belt, which should be no wider than 12mm (1/2"). This would give me about 4-6mm gap to the radiator. I also needed some kind of alternator. I opted for the newer style belt with multiple rips as I suspect it would cause a bit less stress on the crankshaft (might be completely wrong). The next thing was to find an alternator and some pulley with 3 rips, as this is the widest belt, that would fit. I looked on ebay for some cheap used alternator and found some Valeo 110A alternators with 3 and 4 rip belt pulleys. The funny thing was I got two used alternators as the price of a new pulley was higher than the price of an used alternator with the pulley on it. Ok, having two alternators gives me the freedom to make mistakes (and I did brake a brush). The alternator is slightly bigger than the Geo alternator, which is mostly suggested for this conversion, but on one hand I could not find a Denso alternator in Europe at that moment andon the other hand I got the two Valeos for less than 30 Euros. After I got the Valeos I found out they are may be about 2-3 cm (1") thicker in diameter than the smallest Valeo with more than 40 amps (and possibly the Denso one). It was allready too late to change my mind. I had to test it and if the Valeo alternator was way to big I would have looked around for a smaller and much more expensive one (found some used for about 40-60 Euro).
I'll try to describe the whole process, my thoughts and decisions in different situations and provide some pictures of the process. Do not expect a step by step "how to" as you will not get exact measurements or part numbers of anything. Sorry if it sounds disappointing. I'll do my best to explain how one could reproduce my build. ETA for the project was 1 week. Real time it takes is always much more.



ndonev
Posts: 5
Joined: Mon Jul 06, 2015 4:48 pm
Location: Bad Honnef, NRW
Motorcycle: 1985 GL1200A Aspencade

Re: GL 1200 alternator convertion - a somewhat different approach

Postby ndonev » Thu Aug 27, 2015 5:21 pm

For some reason I did not find a way to upload pictures in the forum the other day, so I left the rest of the build for a moment where I am a bit more capable of such things. I also must admit, english is not my mothers tongue, so please excuse the errors I might make.
So, I got a Valeo and directly cut of some "unneeded" parts of it....

I also disassembled the lower fairing and the belt covers and did the necessary cuts on the frame. I'll skip this part as well as may be some stuff covered in the other threads describing how to convert a GL to a car alternator. The damn thing just fits there! I was so happy I believed I can fly :)
Next thing was to check the alignment and space... I had to make sure, I can mount the alternator without moving the radiator forward. So I got the pulley from the second alternator and installed it in place. I mounted the radiator to test the space. I got just enough space to be sure, the pulley would not touch the radiator. Next thing to check was the alignment of the pulley on the crankshaft with the pulley of the alternator. Damn! The alternator was way off. I had to find a way to move it back by about 20mm (4/5"). I looked at it. The only option was to remove the rectifier. I knew, I had to keep the regulator and the brushes on the alternator itself but i turned out they might be out of the way. So I had to remove all the nuts, remove the regulator and cut this joints you can see in the picture above.
Here are the regulator (on the left) and the rectifier (on the right)

It turned out the rectifier is supporting the regulator. That was no big deal. But it also turned out this support is the negative connection of the rectifier which was controlled by the regulator so I had to reuse it somehow. I cut that part of the rectifier with the idea of soldering a thick wire

Without the regulator and rectifier I got the alternator to a far better position and the pulleys did align. Even better - the regulator and the brushes are on the far left side, so they do not get in the way. The alternator is very close to the carburetor but there are a few mm of free space. To prove me right or wrong I had to find a suitable bracket cut a little bit of the heat shield and test-mount the alternator. I also had to cut a bit of the opposite mounting point of the alternator, as it was a bit too big to fit.
As a bracket I used some Honda (may be) Civic alternator mount which was cut to fit.

The next thing was to get a belt. I measured 760mm length but found 775 and 745 mm belts. I got both as I was not sure which would fit better. I used some washers to make the alignment of the pulleys perfect and tried the belts. The 745mm belt was the better choice.

I also got the spacing on the back side quite good:

The second mount point was not ready yet but I did not need to cut more material:

After tightening everything I turned the engine by hand. Looked good. The belt was tight and I got no slack without using the second mounting point as support. So I left it this way with the idea to get back to it when a better idea emerges.
It was time to cut those belt covers. I knew I had to cut them wider than the pulley but I also wanted to do something so that I could keep the dirt away from the timing belts. The pulley I got is a bit wider than the belt and a part of it is not used.

My initial idea was to get some plastic and build a box around the alternator belt and seal it with the timing belt covers. Looking at the pulley I decided against my initial idea. It was way simpler to cut two pieces of plastic to fit under the pulley and fix them to the timing belt covers. So I started cutting the covers

And the plastic:

Then I used small bolts and a lot of gasket maker to fix the plastic pieces to the belt covers and make a good seal between the two materials:

The idea was to let the two plastic parts overlap. This would reduce the dirt getting inside. I also added some gasket maker to one of the peaces with the idea of letting this cured but softer material more or less seal the gap. It did not work that good, but that was the idea. Here the overlapping plastic parts:

I had an old radiator from a server CPU which I trimmed a bit and used as radiator for the rectifier:

The next thing was to solder some thick wires from the stator wires to the rectifier and between the rectifier and the regulator.

I used gasket maker as corrosion protection and insulation. Where possible, I also added insulating tape. The rectifier with the radiator fits perfectly in place of the original one:

The negative wire was connected from the small part I had cut of the rectifier to the rectifier itself. If you follow my steps, do keep in mind the upper and the lower part of the rectifier base are separated by very thin insulation and you have to make sure the negative connection does not touch the chassis (ground). The negative is connected do chassis/ground by an internal switch in the regulator. The control of the regulator was connected to the black wire of the original RR socket

It was time to cut some spoilers. That was a tough decision, but the alternator is a bit bigger and there is no way around that.

And the only part which is visible on the outside:

OK, if you look very closely you will see one more small cut to clear the pulley:

The final check showed enough clearance between the radiator and the pulley:

But turned out the pulley touch the timing belt cover bolt. I grinded about 1-2 mm of the pulley (which cleared the bolt) just to find out the alternator belt also touches the bolt. I left the belt untouched and after some 50 km the belt was worn out by rubbing against the bolt by about 1mm and the noise was gone. I do not think the noise is coming back with this belt.
It was time to think about the cooling system. The original fan was a no go. It was not enough room for it. So I decided to put two server fans - one bigger and capable of better air flow and one smaller "just in case":

After mounting the fans to the radiator it turned out there is not enough space for the smaller one as it hits the belt. I removed it and I am now using just this one:
.
I did not like the idea of having no secondary support for the alternator but I needed the bike sooner than later. So instead of a fixing bracket I have put a quite tough spring as "just in case" precaution.

I know, I will have to rebuild this part in the very near future, but the bike is back on the road with 500km and I will be able to add some electrical stuff as heated grips, fog lamps, DIY heating for the seats and may be some other goodies. I have over 70Amps in excess...

ndonev
Posts: 5
Joined: Mon Jul 06, 2015 4:48 pm
Location: Bad Honnef, NRW
Motorcycle: 1985 GL1200A Aspencade

Re: GL 1200 alternator convertion - a somewhat different approach

Postby ndonev » Thu Aug 27, 2015 5:26 pm

BTW the ETA was doubled... Twice. For different reasons I completed the conversion in a bit over a month. The effective working time was less then 40 hours, so the ETA would have been just about right without all other distractions.


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