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Discussion Starter #1
Scott-

so i'm in the garage pulling my alternator tonight. my car mechanic buddy is there and brought along some snap-on tools including a really good puller with everything you need to pull apart any GM vehicle and a really strong cordless impact gun....and i had some good metric bolts and fenders to grab the rotor. we line everthing up, pull the trigger, and start losing threads on the rotor. we reset and use a socket wrench but have too much leverage to hold the wheel. we go back to the impact gun and start to lose the treads again. phuck.

then i'm thinking, vile told me something in the drunken pits last year....about a rear axle? there's a pile of wheels in the corner, and hey, the 400F axle threads match up with the rotor. a few cranks and and a bit of peen hammer and the rotor jumps off the crank.

good bless you my friend-
tt
 

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I love shit like this...so...TT/Evil..what's the deal...the axle threads in the internal threads of the rotor and seats against the end of the crank snout? Then you turn it in some to tighten up and tap the end of the axle with a hammer...like a Honda rotor tool?

JohnnyB
 

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Discussion Starter #3
jb-

yeah, exactly. perfect. i'm still stoked that it worked. the axle, with it's butt-end just about locks in to the crank. so all it took was threading it in, tapping, thread some more, tap some more....popped off on the third time.

help me understand...the crank is tapered for the rotor to be pressed on. i've heard talk that this holds the press fit better, but also can defeat pullers. what exactly makes the tapered press "stronger"?
and who's woodruff and how did he get his name on the key.

-tt
 

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The taper actually allows for a very tight fit, but also an easy way to remove the stator. If the crank wasn't tapered, there's a good chance the end of the shaft could mushroom, and lock the stator on.
When I'm removing and installing the stator, I heat up the center with a propane torch, which isn't super hot, but hot enough that it doesn't require much pressure to yank it off the shaft. (yes, I said yank it off the shaft)

FR

ps. I went to school with Bob Woodruff, and often wondered the same thing.
 

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Best friend is Tom Woodruff.

Heat and a little tap with a hammer works too.

4.4.7 Tautology

When constructing a definition, it is not permissible to include, as differentiating characteristic, characteristics which are included in the term unless they reveal the intension.
Example :

One cannot define "Woodruff key" as "key invented by Woodruff", since the main characteristic for this concept is the characteristic of shape (segmented)

Woodruff, as the scientific name odoratum suggests, is a strongly scented plant, the sweet scent being derived from coumarin. This scent increases on wilting and then persists on drying, and woodruff is used in pot-pourri and as a moth deterrent. It is also used, mainly in Germany, to flavour May wine (called Maiwein in German), beer (Berliner Weisse), brandy, sausages, jelly, jam, a soft drink (Tarchun), and a herbal tea with gentle sedative properties.
High doses can cause headaches, and very high doses (far beyond those found in the afore-mentioned drinks) can even have mind-altering properties, as well as vertigo, somnolence or even central paralysis and apnoea while in a coma; so, some common sense should be applied when consuming woodruff. Three grams of woodruff per litre of Maiwein is considered safe in Germany.
 

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At one time I did a lengthy study of machine tapers. There are many hundreds of taper ratios and reasons for using them. Some are made for easy release, others are not. Bridgeport machine tapers are made to hold something securely and yet still release easily. Rotor tapers...typically around 5 degrees are there to 1. Center the rotor accurately 2. Allow for a tight accurate fit without have to be pressed on or off. (tapers are not considered press fits). 3. Allow the crankshaft snout to be as thick as possible where stress is the greatest...(a "stepped down" straight shaft would create a very weak point on the crank snout).

Believe it or not, the key is not designed to keep the rotor in radial alignment....the fit on the taper does that...the key is simply to make sure you put the rotor on in the right place. For instance most PVL's (not CB350) don't have keyways. You just tap the rotor in place and install the retaining bolt. The fit on the taper holds the rotor securely enough from spinning on the crank...and the retaining bolt maintains pressure on the taper.

That's all I got.

JohnnyB
 

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quote:
Believe it or not, the key is not designed to keep the rotor in radial alignment....the fit on the taper does that...the key is simply to make sure you put the rotor on in the right place. For instance most PVL's (not CB350) don't have keyways. You just tap the rotor in place and install the retaining bolt. The fit on the taper holds the rotor securely enough from spinning on the crank...and the retaining bolt maintains pressure on the taper.

That's all I got.

JohnnyB
As I remember, my Ducati Diana rotor, which was heavy brass, was fitted so the keyway was a certain distance from the key. It had to be that way for the ET ignition to work. It never slipped on the shaft and was easy to remove. Some early 200 Yamaha's wrere very hard to remove. We destroyed a couple back when I was at Boston Yamaha.

FC
 

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It's amazing what a tapered shaft and a little torque can do. In my shop we're removing flywheels and snowmobile clutches all the time and without the special tools needed to pull them off it would be impossible without destroying them (sometimes they get destroyed anyway--it happens). And this is only 60 lb/ft of torque.

wrench
 

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JB&Camelhairy
How do you explain how a key has a ridge in it due to the mag. moving on the tapered shaft? Not tight enough on the taper?

JS
 

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Champ,
Yes exactly...whenever you see a key that's been dinged sideways by the rotor it's because the rotor has slipped on the shaft. Typically caused by dirt, oil, or small dings on the taper OD or rotor ID, or a retaining bolt that has come loose. Tapers have to be kept very clean and damage free to do their job.
I'm speaking of the small half moon keys. If you have a straight shaft and a long straight key...then that type of key is designed to keep a rotor from spinning on a shaft under torque. And even that is a marginal setup...a high torque load will have a splined shaft.
JohnnyB



Edited by - jbranson on Apr 07 2007 4:28:03 PM
 

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Note what time TTlisted this thread on the forum! 3:30am. I was already on the sofa in his house for an hour getting a french kiss from his dog Chickaree (sp?). Damn dog sneaks up on you! Best darn kiss I had in awhile though..lol.

Yeller'
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Ask not what the wanker can do for you, but what you can do for your wanker!
 

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Discussion Starter #12
quote:
his dog Chickaree (sp?). Damn dog sneaks up on you! Best darn kiss I had in awhile though..lol.
Chicory, you know the root that makes a decent coffee blend/substitute. it's the blue flower that covers the roadsides in summer....for those who care.
 

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cafe du monde, down in the quarter, eating beignets, listening to jazz, with some good coonass coffee.....lots of chicory.

wife hates it, i love it.

bring on the coffee with chicory. bring on the coonasses!

texy
 

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Mmmm... beignets. And NOTHING goes into a pot or cup containing coffee, except coffee. That's adulteration.
 
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