Flywheel and clutch balancing

Been reading about this on all different car sites.

It seems some manufacturer's flywheel / clutch assemblies, intended for internal balance crank assembly, do NOT have good neutral balance.

McCleod, Spec, others.

If seems to be agreed that balancing your flywheel and clutch separately from the crank is a good idea. Even separately from each other, flywheel, then clutch.

Not every machine shop is equipped, or is willing, to do this.

Anyone know of particular shops that will do flywheel / clutch dynamic balancing ?

It’s a balanced assembly. That means you get the flywheel, disc and pressure plate to zero and then it goes onto crank to finish.

I just bolt the plate to the flywheel and chuck it up on our digital wheel balancer and go from there. It gets it down to 0-3 grams which is pretty good to me I've seen guys just bolt them on and trust the clutch and flywheel vendors word

Gus

If you've bought a balanced bottom end then you're pretty much stuck with having to balance the flywheel and clutch separately.

To me, balancing these separately makes absolute sense as you wouldn't want to disassemble a motor for balancing if you ever had to or wanted to change the flywheel and or pressure plate or even switch to an automatic.

As to part two of the OP's question, I know a guy BUT he's in Ontario, Canada !!!

Couldn't be happier with the before/after 8600rpm results from my DIY flywheel/clutch static balancing fixture...
DIY Static Balancing Fixture Webpage

Grant

The flywheel is bolted to the crank flange, the pressure plate bolted to the flywheel, so it makes sense to balance them as an assembly (assuming the PP is indexed, asymmetrical bolt pattern etc.).
However, the disc lands on the other 2 surfaces differently every time the clutch is re-engaged.
How can this work?
The disc's friction part of the radial mass is so evenly distributed that a tiny balance error is harmless. If its perimeter were 3" thick or 30" OD it would have to be neutral balanced separately.

How do simple rotational and dynamic balance differ?
If the pieces were all completely symmetrical in 3 dimensions this would work, but the largest piece (PP) is probably eccentric as to weight distribution in its thickness (front to back distance) even if radially correct.
This means the center of mass is not exactly parallel to the rotational center, but mis-aligned. The PP tries to rotate on its mass axis, and introduces a new vector. Dynamic balance senses this and IDs the correction.

There is so much good stuff on that page. I am going to tighten up the face plated 3-4 slider on my a833 this winter. Thanks Grant!

Great info and impressive approach.

Your door closer provided me with a solution on an issue I was currently working on.