Counterweight & Flywheel balancing issues...

[infernal]

Hello all!

My clutch is out of order and it\'s time for upgrades...

I want to install a lightened flywheel, but I got some questions...

I know that the counterweight for the specific engine series is required (mine is an S5). If I buy the correct counterweight, it will surely not be perfectly balanced as rotors even from the same series differ slightly in weight...
So would it be needed to balance it with the rest of the assembly (e-shaft, rotors, front counterweight)? This thought scares the hell out of me at least...
I don\'t know if Mazda balances the whole assembly or just the flywheel on it\'s own...

Also I was suggested to balance the flywheel and pressure plate assembly together. But how on earth can I center/align the pressure plate to the flywheel if the latter is not attached to the e-shaft? The clutch disc will also be free in there, as the transmission input axle will not be present.

I\'m kinda to heavily confused as you found out. Please help!

Thanks a lot in advance!

Marios

[infernal]

Should I bolt the counterweight on the e-shaft and then just put the flywheel on the counterweight without bolting it, then insert the clutch disc with alignment tool, put the pressure plate, bolt it and remove the whole thing or just leave the clutch disc out of the equation?

Maybe I turn simple things to hard ones. Just bolt the pressure plate on and go to balance it... Is it needed? Have you done it?

!!! I read that aluminium flywheels tend to throw their ring gears off if not balanced correctly or overheated.

What do you think?



*Sorry for all those questions...!!!

[bumpstart]

if your not doing 10 000 rpm then there is no need for the extra balance,, the factory tolerance of the correct auto counter weight is just fine
i have done this countless times with zero issue

buy the N350-11-511 rear mass and a generic light flywheel suit your clutch diameter ( 245mm ,, 9.5 inch )
, drop off the stock lump , fit the N350 mass,, do up the nut
purchase 6 high tensile bolts and bolt up the light flywheel
( the bolt length must be carefully selected,, too long and they will interfere with the stat gear bolt heads )

[bumpstart]

ps avoid alum flywheels,, waste of time on the street ,, and most use a silly unique diameter clutch
\\ moment of inertia
- when you understand the principle fully you will select a one piece billet steel flywheel with the cheese cut holes
-- one that has the ring gear lazer cut around the outside edge
( ie,, ONE piece,, not a flywheel with press on ring gear )

these have exceptionally low moment of inertia,, its all in the mass distribution ,, without the multiple piece construction or silly sized clutch of an alum flywheel
all while retaining use of stock or stock sized clutch components
NB,, you can get light flys with the turbo ring gear ,, but using the earlier 215mm /8.5 clutch if desired

[infernal]

Thank you very much bumpstart!!!


Yeah I read horrible things about ring gear failures...

I decided to buy a Competition Clutch flywheel and clutch. Will write my opinion after the break in.

Thanks for the tip about the bolts. Do you know any shop that can export the bolts here in Greece? I can\'t seem to be able to find anything here...

Thanks once more for the reply!

[bumpstart]

you dont need the mazda bolts,, only something thats the correct thread,, high tensile and 20 mm or so long



this is a mazda bolt , head stamped 12 , i often use GP HT bolts instead
this one is 23mm long,, but must use a 4 mm split washer
anything longer than 20 mm requires a spacer washer




lightflywheel and 9.5 clutch on a 13bt


12a counterweight looks identical to the others
and you should now see why i warn about the bolt length !


you get the idea

[infernal]

OMG only now I realize how tight it gets in there! Thanks!!!

Can I use used Mazda flywheel bolts if I find any at the shop, or are they torque-to-yield type?

[infernal]

Also why the N350-11-511? Isn\'t the rear S5 counterweight the N351-11-521 one?

Oh I\'m bolts and weights confused again lol!

[bumpstart]

n351 is correct
the bolts pictured are just generic HT bolts from another source,, there is no such "mazda" supplied light flywheel bolt
the auto flex plate bolts will not cut it

the spring washer is used only as a spacer,, many times i have seen only flat washer spacer and fully threaded HT bolts
- and all holds up Ok with some thread lock and about 35 pounds foot TQ

[infernal]

Thanks once more bumpstart! It now makes sence to me!

[infernal]

Hi again!

Are the bolt dimensions M10x1.25x20mm?

[infernal]

Thanks so much for this photo! I measured it on-screen with my caliper and made a climax conversion according to the reading on yours. This way I found that diameter is indeed 10mm and thread pitch 1.25mm. :Thumbs-up

So the correct dimensions are indeed 10x1.25x20mm.

I like it when forum co-members allow others use their mind!

Cheers, you rule!

Marios