Clackity clack (don't talk back)/My starter clutch bolts decided to leave

[Dizzledan]

     This winter I installed a shorai battery  and when it warmed up I wanted to ride. Unfortunately I had a problem: the engine would turn over 2-3 times and then everything would cut out and go dark. At first I thought it was the battery, but then I tried to jump it with my car battery and got the same effects. 

I connected it to the problem I was having earlier in this thread:
http://gstwins.com/gsboard/index.php?topic=58274.msg660874#msg660874

     I found out that the bolts on my starter clutch started to back out  , and had been rubbing and getting caught on the starter gear (the large one). I remember the engine clicking slightly around idle to 2500rpm (similar to the valve noise, but from the left side of the engine).

The tops of these bolts should be black:


The shaft should be threaded all the way:


Unfortunately when I pulled the flywheel to get to the starter clutch it fell too quickly and broke a magnet 


I did the old JB weld trick, but was too worried about ruining my stator to put it back in the engine:


I went ahead and ordered a flywheel from a '79 250 (which is supposed to be the same size) and I will update this thread when I install it.

Moral of the story:
Loc-tite your bolts, and don't ignore noises!

[adidasguy]

I would not trust gluing a magnet back together. remember there is a magnetic field. When you break a magnet, they often do not want to go back together because of the same poles coming together at the break. There will be a constant push between the two magnet pieces.

Then you have the engine heat and the oil breaking down the glue.

Replacement is the best call on this one. Does the replacement have the same number of magnets? The poles of the magnets are designed to go with the number of poles on the stator windings. Different arrangement of magnets may not generate any electricity - or not enough.

[Dizzledan]

The replacement only has 3 mangets, longer, but only 3. It was only $22 shipped, so we'll see what happens when it gets here. Worst comes to worst, I can always buy the stator that went with the bike the flywheel came from, right?



Edit: After checking the bikebandit fiche (which I know is not %100 always accurate) it appears they use similar stators with 18 posts. I take it the gauge of the wire, as well as the # of turns on each post has to do with the magnetic magic as well?





Edit #2
Ebay confirms that the stators are prety similar looking gauge wiring and # of turns:

[adidasguy]

It will be interesting to see.
Measure voltage from the stator when you have it running.
We need an EE major to tell us what really to expect.

Lesson learned? (1) Always have towels, neoprene pads or other soft stuff under the bike when taking off parts. (2) No greasy fingers when holding delicate or expensive parts.

Even I, a parts whore, don;t have a spare magnet thingy.

[The Buddha]

1/2 the numbr of poles = 1/2 the charge with the same number of coil turns whic it is likely to be.
However I cannot see a magnet with an odd number of poles. How can there be 1 N and 2 south in a magnet.
So I suspect the 3 poles are actually 6 poles with a radially magnetized curved strip magnet.
The GS'es original rotor I suspect was an axially magnetised complomentary pair X 3.

If you need to understand and visualise what I am talking about - here is a link. kjmagentics.com -
And specifically -
http://www.kjmagnetics.com/proddetail.asp?prod=AX2C45-S&cat=168 - I believe that magnet is actually designed to be ut into an alternator like the GS.

Bolt on a few of em suckers onto a drum and balance it and make 10X the electricity. You need to search for drilled ones so you can bolt it on, these need to be glued, not the best solution.

Cool.
Buddha.

[Dizzledan]

If I buy these:
http://www.kjmagnetics.com/proddetail.asp?prod=AX2C45-N&cat=168
Would I need 3 north and 3 south?
Would drilling affect the magnetism?
Would I need to upgrade the regulator/rectifier to cope with the increased output from the stator?

[adidasguy]

Let me interject a little wisdom here.

This is beginning to sound like someone that buys a Wallymart battery to save $20 then does nothing but complain about battery problems and starts to say the GS is a POS.

Please do yourself a favor and spare the rest of us from woefully sad future tales of grief and get the right part and fix it the correct way.

PS: You can't expect success drilling holes in neodymium magnets. And now you talk of $70 for magnets. Then $120 upgrading the rectifier plus the time and then the endless questions of why it doesn't work followed by an engine filled with shattered neodymium magnets.

Spend a little more to fix it right and fix it fast. You'll be riding in no time and glad you did it the correct way. No worries of it failing or destroying your engine.

Need I go on?

Post a WTB for the part. Someone must have a seized motor they are parting out.

[Dizzledan]

This is beginning to sound like someone that buys a Wallymart battery to save $20 then does nothing but complain about battery problems and starts to say the GS is a POS.

Not at all. It's merely the budding curiosity of electronics which is something that I didn't explore in college. Just questions being asked for information from those who have it for my benefit. It would be cool though to have a GS that properly charges the battery while idling, instead of having to get above 4000 rpm to adequately charge. But if it requires an upgraded charging system which is not readily available (from a sport touring bike maybe?), then obviously I wouldn't go through with it.

[adidasguy]

These bikes charge OK.
Background: Shorai battery and MosFet regulator. IDIOT type LED that goes red, green, amber, blinks based on voltage and change in voltage.

Result: Turn on bike: LED green means OK. Start bike. LED blinks red meaning below 12.4. 10 to 15 deconds later LED goes green again meaning voltage is OK ergo I'm recharged.

Unless you have tons of extra electrical crap, the charging system is fine as is.

(I just saw Kijona looking for a Wallymart battery. Will the saga of "save a dollar now, pay $10 more later" ever end?).

[xunedeinx]

Fix it right now, avoid goats disease.

Fix it later, and find a new engine.

[The Buddha]

If I buy these:
http://www.kjmagnetics.com/proddetail.asp?prod=AX2C45-N&cat=168
Would I need 3 north and 3 south?
Would drilling affect the magnetism?
Would I need to upgrade the regulator/rectifier to cope with the increased output from the stator?

You'd need 3 with north facing in and 3 with souh facing in. However On the GS type rotor (the drum with the inside wall having the mounted magnets I'd rate that swap as near impossible to make reliably. You may be better off with these -
http://www.kjmagnetics.com/proddetail.asp?prod=R411 <- You need a whole bunch of em, you're making a N with 4-6 and then a south the same way.
Yea I agree with adidas though. More trouble than its worth.
OK so having said that, this is how I'd do it.
The first thing I'd do is fabricate a drum probably from aluminum.
Trial fit the magnets and make sure it all will fit.
Then drill holes slightly smaller than the bolts that will go through the magnet holes. And you have to drill from the outside, but as long as they are in the right location they will be fine.
Then tap the holes all the way through.
Then - this is the hardest part. Bolt in the magnets from the inside and use loctite, with bolts that are just the right length that they dont stick through the outside of the drum.

Then balance the rotor, you dont want one side heavier than the other.
Yea the bike's charging system is pretty fine. That means In my book, you can use a N42 or have a little more of a gap between the magnets and teh coil and be fine if you do this. You're replacing somethign like n5 magnets with n40 or better. 8 X the power.

Cool.
Buddha.

[adidasguy]

If you're seriously going to try buddha's suggestion.....

I will probably have a spare engine after you destroy yours

I will be laughing all the way to my paypal account
You better have a spare bike you you have something to ride
So funny - the cost of buying magnets and the time involved will end up more than the cost of the right part and you'll be without a working bike for months.


This would be a good "Handy Man's Corner" segment on "The New Red Green Show" providing you use some duct tape.

I'm going to sit back and enjoy the "Mr Bean" show about the GS500 that destroyed itself as all the magnets cracked (due to screws) then lost their magnetism (due to the heat - read the specs on that type).

[The Buddha]

Neodymium magnets are very heat resistant.
Look for this word "rare earth magnets" when they refer to alternators on the new bikes.
In fact neo's are more hardy than all magnet types with the exception of samarium cobalt.
The thing neo's are not is impact resistant and they are not machinable both of which sa-co's are.
Neo's however cost 1/10 or less than comparable sa-co's.
The rest as he said.

I have a bunch of neo's I keep for various projects, like magnetising my screwdriver yesterday.
5 strokes with the n50 neo's and the screwdriver was now capable of pulling screws from between wafers 1 inch apart 6" down.

I also have a project with neo's in a alternator, however this one is the xs 650 syle alternator which is the opposite of the GS. The rotor is in the middle and the stator is around it. The reason I would do that is cos the rotor is easy to machine, its a solid aluminum round hunk, the thing is easy to drill and bolt on to, and ironically the stock mechanism is far more unreliable.

BTW in 79 or 80 the xs came with a magnetic and sensor ignition pickup, which used a neo magnet fitted onto the rotor. Very heat resistant, else you'd find XS'es stranded all over the place ... well yo udo, but they are stranded cos their owners monkeyed with them and hacked off sheite that was never going to be a problem and replacd wiht with ghetto crap hat gave up on the first ride, or they're not charging or got carb or other issues, not cos they are not igniting the spark.

Cool.
Buddha.

[adidasguy]

  Ruffle his feathers and buddha comes back to life 
We knew you were lurking around somewhere 

FYI:
21. Do I have to worry about temperature with neodymium magnets?
Yes.  Neodymium Iron Boron magnets are sensitive to heat.  If a magnet heated above its maximum operating temperature (176°F (80°C) for standard N grades) the magnet will permanently lose a fraction of its magnetic strength.  If they are heated above their Curie temperature (590°F (310°C) for standard N grades), they will lose all of their magnetic properties.  Different grades of neodymium different maximum operating and Curie temperatures.  See our Neodymium Magnet Specifications Page for more details.  We do stock a range of high temperature magnets, which you can see here.

[The Buddha]

Gaaaaa fraction of its strength, you're starting wiht a magnet with near about 10X the power of stock. OK assuming you're not going to hit 590F with a motor that is still alive (250 max, more like 210-220 oil temp)
The Thing is the stock ones also lose power with heat ... of course they are designed with the lower magnetic power
The first heat up result in a loss of power. subsequent to that temp or less dont cause any more loss.

Dude I know for a fact that the xs650 has a magnet stuck to the outside face to trigger the pickup's.

High temp guys are samarium cobalt. Love those, but they cant hold a candle to neo's for power.

Cool.
Buddha.

[The Buddha]

The BY042SH blocks are made in grade N42SH (SH = Super High Temperature) material. The SH material means that the magnets can be heated to 302° F (150° C) without any loss of magnetic strength, unlike standard neodymium magnets that begin to lose strength at 176° F (80° C). Suitable for many high temperature applications.

This size is also available in grade standard N42 as part number BY042.

These are n42, normal GS magnets are under n5, I suspect the high temp neo magnets are just normal neo's that have been heated to that 302F.
Either way, n42 magnets in a GS alternator is enough to light up a small town.

BTW I am replacing n25's in a ess heil amt with a waffle board made of n50's mounted on a frame right in front of the bugger.
Double the magnetic power in 1/10 or less the distance. See Mr Oskar Heil's creation twist with my volume knob.

Anyway n42's are over kill, heck n35's are too much. N52's in the heat of a GS motor will probably drop to n50's. If you're that desparate ... get n60's they are more $$$ but I would suspect they would retain atleast 55 after the heat cycles.

Cool.
Buddha.

[The Buddha]

Ruffle his feathers and buddha comes back to life 
We knew you were lurking around somewhere 

And dude I never went anywhere - you got your jets didn't you ... in barely a month, see that's proof I am around.

Just cos I dont respond to every jetting and idling and carb question just means I have decided to have some mercy on the server and john who prolly pays a cent for every word we type.

Cool.
Buddha.

[adidasguy]

WOW! I really must have struck a nerve. 3 posts!

Yes, I did get the jets. Thank you.

[The Buddha]

Shut up ... slow day @ work.

However for the first time since the 90's I managed to leave 1 job that was rapidly closing on me and get to another without losing a single day ... I dont recall doing that after 1996-97 if I remember. However I did it 2-3 times back to back in those days. Living in the bay area being in IT and being extremely mobile and 25 didn't hurt 1 bit, neither did the fact that I was commuting by bike (GS to be precise) and would be able to cover all of the bay area in under an hour ...
Heck there were places I worked @ where for the whole time I never took my truck. That inspite of a bike that died on the way back from work one day.

Anyway for being in podunkville this is an acheivement.

Cool.
Buddha.

[Dizzledan]

Thanks for the lesson on magnets Buddha. I'll save that for when I get bored...and a lathe.

Got the new flywheel today:


It's a little shorter (1mm) than the stock one, but the same diameter




I mounted it up, and found a new problem. My ignition rotor is bent or not sitting right. The bike fires up and runs fine (the ignition rotor doesn't hit the pickups), but it's noticeably wobbly when running. Does this pose a major problem that could strand me someday? I took it off and checked the pin (still there) but the back of the rotor has a little dent next to the cutout where the pin is supposed to sit.