Balancing

Bottom End (crankcases and crankshaft)
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restless
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Balancing

#1

Post by restless »

Hi at what point do you have to rebalance your fly wheels. Do you have to do it every time you change your cylinder bore size or can you weigh your new pistons against your old pistons and see if they are close to same weight or does every thing have to be bang on.
Thanks Bill
RUBONE
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Re: Balancing

#2

Post by RUBONE »

It all depends on what your use is. Maximum performance or basic cruising. Factory H-D pistons and associated parts were within a "range" of weight and stock flywheels are balanced for that range. Most factory engines work just fine as they came and were never re-balanced. High performance is a different path altogether.
58flh
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Re: Balancing

#3

Post by 58flh »

The Key word to what RUBONE said -(Hi-Performance is another matter!)--I have seen stock motors with 1-jug at .040 & the other at .060!--Theres no difference in running!--A lot of times The Dealers would olny fix ONE CYLINDER that was bad!--So one might be stock bore & the other Bored over.It don't make a difference on a STOCK ENGINE as THERE is olny 1-crankpin! & that = 1-throw on both rods.The motor don't even know its running 2-cyld.s!.I personally have always done both.But I ride with guys with old bikes & 4yrs. later its Top-End time & I find 2-different size bores!.The bike ran great & not one of us new it!.Until 30K later & it was time for a check-up.-There was nothing wrong with the motor !-It ran FINE!--But that kind of mileage on a pan ,is time for a look-see.New rollers on the lifters -Re-Ring or bore,etc.---I don't want to get to much off te topic--(Read FLYMASS & Balancing Factors in K-BASE for better understanding).Theres no doubt that quite a few guys here probably found different bore sizes at some point in rebuilding mills.It screwed my head-up when I found my first one--But DAD said its how its done & nothing wrong with it!--He also said if I tried it on my 66-BB Chevy It would blow parts as soon as it fired.I Learned the WHY EXPLAINED HERE on this great SITE!.It just shows you -you can never know everything.---Respectfully---RICHIE
mtnmn 1830
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Re: Balancing

#4

Post by mtnmn 1830 »

Hi Ray
good job on the reverse engineering & balancing. I understand it.

mtnmn 1830
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