Let’s talk crank balancing

tried finding a better pic, no luck...

the only engine design that can be fairly well balanced for all speeds with only one piston.
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the piston follows a true sinusoidal curve. unlike conrods/crankshafts.
these do become perfectly balanced in a 90 degree v twin layout.

balancing is a joke.
 
tried finding a better pic, no luck...

the only engine design that can be fairly well balanced for all speeds with only one piston.
marlonb2.gif


the piston follows a true sinusoidal curve. unlike conrods/crankshafts.
these do become perfectly balanced in a 90 degree v twin layout.

balancing is a joke.

Another of my passions live steam engines. At one time I use to have about 180 now I only have about 70. LOL My youtube videos.
https://www.youtube.com/user/Jeff46u/videos
 
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I am going to post some videos and links about balancing. I am not saying the way they do it is correct or not correct just want to get some input. All so on some of the videos read the below comments.
Thanks
Jeff

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I do not see how you can get an accurate rotating and recuperating weight with out disassembling the crank?

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a single cylinder engine with a conventional crankshaft-connecting rod cannot be balanced. It can only have the balance factor adjusted to minimise vibration in the most desired operational rpm range.
 
a single cylinder engine with a conventional crankshaft-connecting rod cannot be balanced. It can only have the balance factor adjusted to minimise vibration in the most desired operational rpm range.


I disagree you can do a very good balancing job if you disable the crank. No a Harley is not a single cylinder but uses a male and female rod with only one cowmen crank pin and I balance them all the tine.l Been doing it for 40 plus years. To do these cranks I will have to machine mandrels for it.

What do you thing balancing is? It is moving weight around or removing or adding to cut down on vibration.
 
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This is on an earlier HD crank after all the weighting and figuring is done. Yes, it has removable shafts for the PTO and pinion but the later wheels have them made into the flywheel. But they do make mandrels for these wheels as well. These are what I am going to have to make as well as a adjustable bob weight. Like I said HD uses a cowmen crank pin with male and female rods.

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You can balance the flywheel all you like, but when the single cylinder reciprocating components are attached, the engine cannot operate as a balanced assembly.

You can have your opinion, but you are still wrong.

A 45 degree Harley Davidson configuration cannot be properly balanced, unless the V-angle is opened up to 90 degrees.
Honda did a lot of research into closing up the V-angle for it's premier 4-stroke motorcycle racing engine, to give an acceptable level of vibration, but 72 degrees is the tightest V-angle possible before balance becomes unacceptable, and a balance shaft is required.
 
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You can balance the flywheel all you like, but when the single cylinder reciprocating components are attached, the engine cannot operate as a balanced assembly.

You can have your opinion, but you are still wrong.

How many cranks have you balanced? Have not done any bicyclist cranks YET but have done hundreds of HD cranks. The reciprocating weight is figure in to the bob weight!!!!!!!!!!!!!! Show me a lot about your knowledge as you do not have a clue. Only one way I to know for sure and that is do it myself! Prove me wrong since you think you know so much!!!!!!!!!!!!!!!!
 
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