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Discussion Starter #1
Hello everyone.
With some good help from this forum we determined that the generator rotor was the final (hopefully) reason the charging system isn't working.
We purchased the special tool from Honda to jack the rotor off the taper on the end of the crank shaft. the special tool is two special bolts
The inner bold has no head and threads into the tapped hole on the end of the shaft. The outer bolt is hollow and threads into the rotor over the inner bolt. The outer bold works against the inner bolt and in theory pulls the rotor off the taper.
We tried hard last night and succeeded in stripping the cast iron threads out of the rotor.
The fact that the stator was brand new when we bought the bike leads me to the sad conclusion that the seller may have known the rotor was frozen on the shaft and decided to sell the bike.

Any suggestions how to get the rotor off? I don't really want to wail on it with a hammer since every impact ends up on a bearing somewhere. We have removed the core wire all that is on the bike now is the inner half of the rotor. It is a massive chunk of cast iron so I don't know if we could heat it up enough with a mapp gas torch or even if heating it up will help.

I'm hoping that there is some way short of pulling the motor and taking the crank shaft out. I suspect you have to pull the rotor off to get the crank shat out of the block anyway.
 

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If there is no way to use the Honda tool anymore, you might be able to find a 2 or 3 jaw puller to grab onto the rotor with and pull. The idea is to load up the puller with tension and then whack the central puller screw with a hammer, the shock of which will break the tapered connection between the crankshaft and rotor.

Edit: Noticed you're from Amherst. Harbor Freight is pretty close to you - probably could find a cheap puller there.
 

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Discussion Starter #4
Thanks for the suggestion of the puller and raping the center screw of the puller.
I went to harbor freight and got the puller lubed the center screw. Cranked on it all I could. Raped the screw. Nothing.
Tried heating the rotor and then raping again. Nothing.
I'm wondering now if I can get 1.5" cut off wheel on my Dremel tool positioned to cut a groove in the rotor. Basically cut the darn thing off.

Any other ideas out there would be appreciated.
 

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Wow, did you give the center screw a good whack with a big hammer? They won't come off without it.

If it's still not coming off I think cutting it is going to be your best bet. Never had to cut one off, though..
 

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Discussion Starter #6
It was hard to get the tree jaw puller onto the rotor. There is not a lot of space behind the rotor. I cranked on the puller until the center screw started to bend. Stretched the treads all to h*ll.

How big a hammer are you suggesting? I hit it pretty hard with a claw hammer. I have bigger hammers I can try. Is there any concern about what inside the bottom of the motor that is absorbing the shock? BTW thanks for your help.
 

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A big claw hammer should be fine - must really be stuck on there! I use a big ball peen hammer. Any normal size hammer should be fine to use without damaging anything in the bottom end.

I think to if you can't get it to pop off, you either have to cut it off, or remove the whole crank and have it pressed off. Either way, ouch!
 

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Discussion Starter #8
Well I have a big ball peen hammer as well. I don't have much use for it arround the house. I will give it a try.

Can you get the crank shaft out of the aluminum lower engine housing without removing the rotor?
 

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I have no direct experience with your exact year/model, but other old Hondas I've worked on - yes. Though removing a crankshaft usually involves completely removing and disassembling the engine/transmission.

Edit: Make sure the puller is only pushing against the crank, and the jacking screw isn't overlapping onto the rotor somehow. I've had to modify them before to prevent this.
 

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Discussion Starter #10
The bolt that clamps the rotor to the shaft has a countersink in the center of the head. I believe this is intentional so the tip of the center screw of the puller can be but into the countersink. I have the clamping bolt backed out so there is a 1/32 gap between the body of the rotor and the underside of the head of the bolt. This gap should allow the rotor to move if it breaks free of the taper.
Tried the big ball peen hammer. No go.
I'm going to buy a stack of abrasive wheels for my dremel tool and see if I can cut it off.
This will be a long slog if I can even get the wheel positioned to make a cut.

Thanks for your comments and support. It makes it a lot less depressing to have someone to talk it over with. I bought the bike for $600 and have another $400 into it in parts.

Not best $1000 I have ever spent.
 

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I buy cheap bikes all the time for projects. It will be a nice bike once you get the bugs worked out of it.

How easily can you keep the abrasive grit out of the engine? Is the stator area open to the rest of the crankcase?
 

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I just now thought of this, but do you have a plumber's torch? Just a regular MAPP or Propane one? Might try putting some tension on it and then blasting the center of the rotor a bit.
 

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Discussion Starter #13
I don't know what is behind the rotor but I believe the aluminum housing seals the core of the engine from the rotor.
I have a mapp gas torch. I tried that last night. No go.
 

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This might be a stupid suggestion but have you sprayed it with liquid wrench or pb blaster?

Let it sit over night, hit it again in the morning
 

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Discussion Starter #15
I sprayed it with wd40 last night but it was still hot from the torch. Do you think liquid wrench would be better?
 

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Watch it fall right off...

:rolleyes:
 

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Hi there....

I own a CB900C as well... No idea if this will help you but here's what happened with mine..

I had to bring the bike to a mechanic for an unrelated problem... When I got the bike back I immediately noticed that the bike's lights were not getting brighter when I revved the engine, which for this bike is odd..or just wrong.

I didn't think much of it then since I was still new to the bike.. Later however I began to realize it was not charging... I tested the battery and based on the reading I realized that the charging system had stopped charging just about when it was at the shop, not before and not after... This to me indicated that either they had done this intentionally or accidently, disturbing something, or leaving something half connected..

I went back to the shop and the guy immediately says you need a stator or some other expensive part.. But I wasn't buying it... Literally.. I told him no, it stopped working when it was here and I don't believe in coincidence ..

To make a long story short, there is a white plug around near the battery.. It has I think, 3 wires on each side, might be less or more but you get the idea... The entire problem with the charging system was this plug.. I spoke with some of the guys on the DOHC forum and they said these plugs are known to fail. My guy just soldered the wire back into the connector and bang no more charging problem... So it's not always the big stuff, sometimes it's something simple, but hard to track down.
 

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Discussion Starter #20
Hi Jim
Thanks for the comment.
I know the connector you are talking about. We found it half melted. We removed the bad male half and used spade lugs on the individual wires to reconnect to the female receptacles in the remaining good half of the connector. Seems to work ok except when you have to disconnect the connector the free wires touch and pow there goes the main fuse. I need to replace both halves with a good connector. Not sure where to find one. Thinking about using a trailer light connector.

Interesting wrinkle to the story. I measured the voltage at the black and white wires that energize the rotor and only measured 9.5 volts. Tried running 12 to these lines from the battery. When I did that I got the 50 volts AC output from the three yellow wires from the stator.

I decided to replace the rotor anyways because I was only reading 1 ohm between the slip rings and only 10 ohms slip ring to ground.

Now we are a bit pregnant so to speak. In the process of trying to remove the rotor we grabbed the outer half with the gear puller and tore it off. So now it is new rotor or bust.

We are attacking this on two fronts. Everyday we work on it we spray it with PM blaster and try to pull it off. If that doesn't work we are Slooooowly cutting it off with a dremel tool and cut off wheels.
 
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