ADVANTAGES BALANCING THE CRANK/FLYWHEEL ASSEMBLY ON THE BIG INCH MOTORS

[sacbluescat]

We are in the process of putting my partners Rev Performance Monster 114 " together and I am very curious to see if it is going to be much smoother then my 114" stroker build . I might be regretting not balancing my crank / flywheel assembly when I put my 114" stroker build together. I do get a "Potty mouth" load of vibration out of it , also believe their might be some other advantages , such as engine longevity and a faster revving motor ??

[Ohio HD]

I can't think of any draw backs to balancing the crank, it can only be a positive for the motor. It may help thinks live longer in there, and may also add a little to the upper end HP. I would balance it. If for no other reason, as you stated, it may be a smoother ride.

[Hillside Motorcycle]

No way, could those wheels be even close to being balanced for that large bore pistons.
Scott

[prodrag1320]

BTW,balancing wont help with reving any faster

[88fxstc]

My bagger has balanced crack and it is surprisingly smooth for it's size...131. It's as smooth or smoother than it was at 110/.

[noliners]

Dark horse prepped S/S crank in my 131.  152 Hp/ 156 Tq  15,000 miles. Best 800 bucks spent!

[FLTRI]

My '03 117 build with balanced flywheels is smoother than it was as a stock 88".
Just my experience,
Bob

[RevFastEddy]

Size doesnt really matter much in smoothness. It is the % balanced used. Anywhere from 50% to 60% balance....  one will be smoothest at low rpms (2000) and the other will be smoothest at high rpms (6000)...  So if it is smooth off idle it is a mirror shaker at 6000 and if it runs like greased B*tch at wot than the off idle will be a shaker... cant have it both ways unless you get a B motor and the counter balancers  smooth out most of the differences in vibration. Not a cure but a good bandage

[88fxstc]

Size doesnt really matter much in smoothness. It is the % balanced used. Anywhere from 50% to 60% balance....  one will be smoothest at low rpms (2000) and the other will be smoothest at high rpms (6000)...  So if it is smooth off idle it is a mirror shaker at 6000 and if it runs like greased B*tch at wot than the off idle will be a shaker... cant have it both ways unless you get a B motor and the counter balancers  smooth out most of the differences in vibration. Not a cure but a good bandage

Not saying your wrong, you probably know more bout the technical end of this stuff than me, I'm not even sure what they mean by 60% balance factor, but, my motor is just smooth throughout the RPM range . It don't rattle fillings at idle or shake the mirrors unreasonably at high RPM's. And I know what a shaker can feel like, my evo softail, chit , I don't even bother with the mirrors on the highway, I turn my head and look when I'm on that bike.

[black]

 them b moters are nice scott has some nice ones out there 

[N-gin]

If your getting a lot of vibration you might want to look at your tune.
I have noticed with mine that if its out of tune it will vibrate my wrists numb. My engine is balanced too. Change the tune and it is smooth as a Honda.
I V-tuned for the longest time . It wasn't till I took it to a shop to get the exhaust sniffer tune. Wayyyy smoother. Then I tuned using the wide band sensors from Twin Tech,  now I don't know how it can get any better..
Balance all you want of the tune is not right it will vibrate.

[locker55]

If your getting a lot of vibration you might want to look at your tune.
I have noticed with mine that if its out of tune it will vibrate my wrists numb. My engine is balanced too. Change the tune and it is smooth as a Honda.
I V-tuned for the longest time . It wasn't till I took it to a shop to get the exhaust sniffer tune. Wayyyy smoother. Then I tuned using the wide band sensors from Twin Tech,  now I don't know how it can get any better..
Balance all you want of the tune is not right it will vibrate.

N-gin , We will see how smooth.... Date and time is set for Bob to tune this Wednesday at high noon.
Sacbluescat will trailer it to Hayward from Sacramento because it has a 95" build tuned on it now.
We will be finishing the build tomarrow.
All I can say is don't touch the top end without doing the bottom.