Balance Factor

Gidday Alan. (Acrotel)
Mate, I am really curious here about your engine. I assume from your posts that you have built or had pulled down your engine, and you are talking from experience about what you found and new bits put in.

Can you please tell me if you have self aligning bearings fitted to your motor. How many hours has your race bike engine done on these bearings. You certainly have done the unusual if this is the case.

I was under the impression that self aligning bearings were totally unsuitable. If self aligning bearings work well, you have done a unique thing here, and please share with us the story of how you got a reliable race engine with these bearings.

I am not taking the piss, but you seem to have done a unique thing here and I am sure a lot of others will want to know that this is indeed possible.

Respectfully Bradley

Dances with Shrapnel said:

Matchless said:

I too am sick & tired of hearing this tosh about barrel shaped rollers. I've measured the earlier Ransome & Marles 'Superblends' & also the FAG type. The rollers are parallel with a slightly larger end rad. to stop them digging in to the outer race. The barrel shape rollers are single & twin row self aligning bearings. A different thing altogether & used to accept misalignment between bearing bores / housings.
Martyn.

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+1

Just about every rolling element bearing comes with specifications for allowable misalignment. "Superblend" - just a marketing moniker; probably hatched by Norton to smooth over public perception when the Commandos began to frag their bearings.

As for the acotrel's diatribe on balance factor - it's pseudoscience. Yes, please put this rubbish to rest.

Click to expand...

I love it when people say what they mean, to the point and concise ...

Either someones telling porkies , or someone ran a 89 stroke Norton to 8000 , with peak H.P. at 7.400 .


" ENGINE "

Power approx 62 Hp @ 7.400 rpm . motor proved safe to 8.000 rpm . but ' we were getting 7000 on the day ' ; stated in the second paragraph .
Suppose it depends if it was before , or after Lunch . As it were . :wink:

Mayas well go here as anywhere .




INTRESTING . its the Tourque , gearing , and power to weight ( Tourque to Wt. :shock: and weight transfer / TRACTION then , that snots them in the quater . :lol:









http://yeoldecycleshoppe.wordpress.com/ ... y/triumph/ American Eagle :

NOW ,
if it were just the Rotation Imbalance , we might believe someone . B U T ,
theres rotational acceleration / deceleration per revolution . Rod Angularity ,
B.M.E.P. Piston Inertia , Rod Inertia , torsional loadings derived from these .
Then Rotational and Lateral ( to Axis ) loadings from the Chain . Reversing
vertical pull / load from + to - above to below , throttle on to off . And in part
per revolution ( flutuation ) in a Two R P M cycle ( for starters - before cyclic
load patterns are considered .

So , WHERE EXACTLY is THE Crank under maximum strain ?

The Maximum FRORCE if applied though a greater part , could impart less concentrated strain
than another through a smaller component .

For Example . :lol: a load ACROSS the webb below the crankpin has about 1 / 3 the material
as that load considered Along the Web . :shock: If it Were .

The point being theres some feardully complex patterns of load & its distribution & path / paths ,
than simple rotational eccentricity of mass .

http://mh-mechanicalengineering.blogspo ... hafts.html

and thats not the half of it . :twisted:

Note ; usually the 750 race class Dunstall info refers to a 7500 rpm redline . Being front line raceing machines Circa 1970 , the maintanance / replacement schedule would have been acceptable then , when winning .

Here theyre claiming peak power at 7000 , presumeably with the ' Dunstall ' Head , Full Hemi big ( intake ) valve . Comparable if not the same ? as the Norvil / Thruxton Race Shop P. R. / F 750 cylinder head . :?

I totally fail to see how this thread is putting anything too bed Alan, just the same ole same ole to me....

...balance on a standard road bike works......with the isolastics...rigid mount (it not a Commando anymore) so something else....race bike do something else to suit the motor you built...one size actually does not suit all....oh what a surprise!

Use whatever factor works on your Seeley.....

Prtty sure I have had my crank balanced at too high a factor, because I did it too early in the bike build....solution...build it anyway and test...adjust to suit...if necessary....