flywheel balancing

[charvey]

Hi all,
I am looking to get a flywheel balanced I live near Stanford Lincs., and am looking for somebody in the near area to do the job for me, have been told about T and L Engineering near Bedford, has anybody used them they seem to know what they are doing and talk about 60% balance factor for an Ariel I am not racing or anything just a standard bike 39 500cc. Regards Clive.
Just got a new piston from Allen the singles man and its really nice and shiny just the job thanks.

[will_curry]

T & L certainly know what they are doing and have balanced several A10 and A65 cranks
for friends of mine but with these it's as much about balancing one journal to the other.
I'm not sure whether the effect would be as noticeable with a single but it's made
an appreciable difference to my friends' twins.

[david.anderson]

Do not use a 60% balance factor unless you want the fillings shaken out of your mouth. Ariel used 65% in all their singles, but anywhere from 65% to 67% will be good for the road.
David

[nevhunter]

Vertical twins need to be dynamically balanced because of their width. 65% is the FACTOR for Ariel and Rudge singles. Norton singles use more. Nev

[MGriffin]

Balance Factor is an interesting area.
From my persepective though, I will refrain from entirely subscribing to an Ariel “default” or “recommended” 0.65 BF given that:
a. information provided in Phil Irving’s book recommends to, “adopt the concept that in all cases, it is ideal to get an engine to run smooth in the speed range at which it is intended to operate for the majority of its life”,
b. I have found numerous cases of manufacturer’s singles with varying BFs by design, and
c. my 28 Model A 557cc engine left the factory with a BF of 0.53.

That said, my VH currently has a calculated and intentional BF of 0.65 and is very smooth at 65 to 70mph but regarding the 28, I dont anticipate to operate it at anything much greater than 50mph, so…..I anticipate it will likely peform acceptably well with the now intentional BF of 0.60. This considers the use of original internal components such as an OEM piston and pin and the original rod and flywheels but an expected rise in useable rpm from a mild improvement in tune.
My take anyway.