So, Bachmann...

[SkipGear]

David,
 Cost and size were most likely the reasoning. Yes, a 5 pole can be made small enough to fit in a Z loco, but that motor would not perform well in an N scale loco. It would not have enough torque (power) to pull the N scale trains we want and would most likely burn up in regular use.  The Maxon motor that Microtrains uses in their diesels is a nice motor but would not perform well under the loads of an N scale loco. Just like an N scale motor is not enough to power an HO loco (believe me, I have tried, even with gear reduction).

Kato went with a 3 pole mainly due to size. The GS4 motor is much smaller in diameter than their standard diesel (GM-5 style) motor. A 5 pole motor that small would more than likely not pull the entire 14 car daylight set up a 4% grade due to the reasons I explained much earlier in the topic.  A 5 pole motor could be made to satisfy the design criteria but the cost would be substancially more. It would require rare earth magnets and probably a new piece of equipment in the factory to be able to wind the smaller armature. It would probably also require higher gear reduction. The result of the higher gear reduction would also mean more motor RPM and noise. With all the effort Kato put into the GS4 to issolate the motor noise from the frame, gearing a 5 pole higher was probably a design consideration.

You have to look at the whole picture and how it works as a package. I really don't have any issues with the GS4 other than the overly complex design of the chassis. I never plan on switching with a GS4 so slow speed performance is not as important as over all pulling power.

[SkipGear]

Sorry I started this topic. Ill keep excitement at being able to find what I want, and hoping for more, to myself from now on.

Thanks for clearing up the motors Skip. Learn something new every day.

No problem starting the post. It has been entertaining.

Oh, and while we are at it, there is a new most disapointing loco at the top of my list... Kato GS-4.

Mine has now gone through 2 Tsunami decoders as of tonight. I believe I finally figured out the problem. In their effort to make the loco quiet, the vibration issolation motor mount allows the motor to move too much in the cradle. That, along with the fact that the rear flywheel was not pushed on far enough and could rub the frame, constitued a very hard to chase down intemittent short circuit which just took out decoder number two. The first one lasted about an hour, this one, about ten minutes. I have now probed and probed and can not recreate the short. I think I have solved the problem with a combination of gluing one side of the cradle to the frame and re-aligning the flywheels so they are in the middle of their frame pocket, I hope to have it fixed. The first decoder should be back in from Soundtraxx in the next few days, just in time to reuse the box and ship this one off.

Why not line the "pocket" with capton tape?

The S.

The problem was the flywheel wasn't pressed on the shaft all the way and it was rubbing the end of the cavity. The clearance was less than the thickness of a piece of Kapton tape. After pressing the flywheel on the shaft farther and centering it up in the pocket, there is now plenty of room. The other issue is that the cradel is so sloppy that the motor can move side to side and even twist side to side, allowing the front flywheel to contact one frame side while the rear flywheel contacts the other and creating a short that way.

As much as I like using the drawbar for contact between the tender and loco, I am going to bypass the upper (motor contact) drawbar so this can't happen again. There is just too much slop in the motor mount that there are numerous places that the flywheel can short out the motor sub frame pieces.

The GS4 runs great when everything is right but it is a horrible design when things are not lined up perfect. It rivals anything Bachmann has done in the past, in uneeded creativity/complexity.

PS. The reply editor for this forum has some issues. After about 15-20 lines of text, it scrolls randomly to whatever section of the post it wants to and won't keep the area you are typing in view.

[DKS]

PS. The reply editor for this forum has some issues. After about 15-20 lines of text, it scrolls randomly to whatever section of the post it wants to and won't keep the area you are typing in view.

Sounds like you're using IE8. Click the Compatibility View button (looks like a little broken page, to the right of the address bar). This should fix the problem.

This is a FAQ that we keep answering in the Admin section, and the thread keeps getting deleted. No idea why. Guess someone wants people to continue having this same problem and asking this question over and over.

[SkipGear]

PS. The reply editor for this forum has some issues. After about 15-20 lines of text, it scrolls randomly to whatever section of the post it wants to and won't keep the area you are typing in view.

Sounds like you're using IE8. Click the Compatibility View button (looks like a little broken page, to the right of the address bar). This should fix the problem.

This is a FAQ that we keep answering in the Admin section, and the thread keeps getting deleted. No idea why. Guess someone wants people to continue having this same problem and asking this question over and over.

Thank you David, that fixed it.

[victor miranda]

far be it for me to agree with skipgear....
I have to state that I would emphasize different aspects,
that said, I consider this post a different set of eyes on the subject
and you can decide how far apart we are.

The GS4 is large enough that kato could have fit their normal motor.
so that leaves why the smaller three pole?

That kato 3 pole is a well done motor.
So while I am sure it be cheaper, it has qualities that
make it an expensive 3 pole motor.(brush barrels and strong magnets)
so cost cutting was not the entire reason.

One more piece to this puzzle may be that I  know a kato mike will
do a slow motor roast if it is equipped with two axles of traction tires
and set to pull all it can.

And, I am guessing here, that is about the same performance numbers
as a loaded gs4.

This is where skipgear and I come back together...

Kato seems to be using the motor to get better power ratings...
or a motor that runs cooler at slow speeds
there are a lot of different ways to say that.
those very strong magnets are the reason.

To expand on the conjecture a little further
I think Kato is trying to find ways to use the new motor they have.
Since it is smaller than their 'normal' 5 pole,
I expect Kato will be making smaller locos soon.

Now... I want my cake and eat it too.
I'd like to see a 5 pole arm in place of that 3 pole armature.
I think that would be an amazing motor.

v

[wm3798]

Is it me or does Victor always reply in Haiku? ;D

[SkipGear]

Is it me or does Victor always reply in Haiku? ;D

Thanks, I needed that after fighting a stopped up drain and loosing.

[Dave V]

Is it me or does Victor always reply in Haiku? ;D

Bachmann gives us steam
Lots of little parts flying
Three pole motor fail.

Big mountain loco
Shiny pipes, details abound
Cannot pull tender.

[mcjaco]

Is it me or does Victor always reply in Haiku? ;D

I asked the same question on Atlas a few weeks back!   

[Packer]

Is it me or does Victor always reply in Haiku? ;D

haha. Maybe he works for "them" ;D

[GaryHinshaw]

Is it me or does Victor always reply in Haiku? ;D

I call him the Bard of the A-Board.  (And now Railwire.)

Long ago there was a thread on the A-Board about train songs.  My favorite response was Victor's: Love Me Tender.