I never had an issue not running one. I couldn't even tell after I removed it. I just cut/broke the chain and left all the assembly in there so my oil level on the dip stick stay'd correct.
Its good for 8-12whp depending on what kind of RPM your motor makes power at.
The rotating assembly isn't balenced with the "balence shafts" so removing the chain doesn't do anything to the balence of the motor, its just like removing power steering or an A/C compressor.
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86' snapper electric powered lawn mower.
95' F-350 crew-cab powerstroke 5-speed 21.63mpg
03' G35 6-speed coupe. Grey on black.
02' wranlger apex edition with EFI 5.0L 302 SBF. 5.5'' lift, custom 4-link 8.8 in the rear, high pinion D30 front with locker.
A wise man once said, " I didn't wash my hands b/c my D**K is cleaner then ANYTHING, in that bathroom"