I feel a bit wobbly

[Stan Thomas]

This should keep the chatline going for a few weeks!!!!

What do we know about “wobbling” flywheels?

Is it a science with calculable formula, or is it just suck-it-and-see?

Is it worth it? at all?

First in the arena I present (da-Dah) Roger Moss.

Roger. over to you…..

Stan.

[dave bushell]

I always thought you were a bit unstable Stan – then you go and spoil it by meaning flywheels!!
Regards
Dave

[Roger Moss]

Hi Stan and all–
We get quite a few flywheels with damaged tapers and have made equipment to sucessfully regrind the tapers.
If damaged tapers result in wobbly flywheels, than the engine will seem rough.
Reverting to original standards of accuracy will definitely help.
Scotts were good engineers.
When they said “Made to limit gauge” They meant it!
If accuracy has been lost over the years, it can be regained.
What man has done before, can be done again.
Unfortunately, if Scotts made 1500 bikes in 1929, then economies of production scale were vastly different to taking a single engine and renewing it as a “Toolroom Special”
As I said before–
It is not a case of what can be done —
Only a case of what can be afforded!

[Roger Moss]

Hi Stan and all–
We get quite a few flywheels with damaged tapers and have made equipment to sucessfully regrind the tapers.
If damaged tapers result in wobbly flywheels, than the engine will seem rough.
Reverting to original standards of accuracy will definitely help.
Scotts were good engineers.
When they said “Made to limit gauge” They meant it!
If accuracy has been lost over the years, it can be regained.
What man has done before, can be done again.
Unfortunately, if Scotts made 1500 bikes in 1929, then economies of production scale were vastly different to taking a single engine and renewing it as a “Toolroom Special”
As I said before–
It is not a case of what can be done —
Only a case of what can be afforded!

[Stan Thomas]

Hi.

Youv’e got me all wrong!

It is a little known fact that there is insufficent material on a Scott crank cheek to balance the reciprocating mass of the upper part of the rod and piston.

Instead, we have to rely upon the out of balance forces being absorbed by a masive flywheel (and bolting the crancase solidly to the frame – but lets not go down that road).

Any road up, it is possible to part-drill holes on the side perimiter of the flywheel, with corresponding part-holes diametrically opposite 180 degrees apart.

The effect is to purposely set up an out-of-balace of the flywheel to cause it to wobble – the trick being that the “wobbly” cancels out the wobbly caused by the unbalanced cranks – resulting in a smoother engine.

Get it???

Stan.

P.S.

Glad to see Dave Bushell has learned to read.

[Stan Thomas]

Hi Technocrats

You’ve all mis understood me – so I will say this only once (or perhaps twice for Dave Bushell’s benefit).

Because there is insufficient material in a Scott crank, it is impossible to balance the reciprocationg portion of the con-rod and piston assembly etc.

Instead, the lesser expedient is used of swamping the out-of-balance forces with a fairly massive flywheel. With me so far?????

Well, I know experiments have been done to remove two areas of metal from the side of the flywheel rim to purposely cause an out of balance effect or a “wobble” – the intention being that this induced wobbly counterbalances the forces created by the unbalanced cranks
(“unbalaced cranks” not being a reference to the recent A.G.M.)

Now are you with me?

Does anyone have info, calculations or procedure etc. of how flywheels can be so doctered?

Regards to all,

Stan.

[Author]

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