balance shaft removal

[jdm92_accorn]

has anyone removed their balance shafts or took the belt off? is there any excess vibration at higher rpms?

[90goldcoupe]

Supposedly the added vibration shortens the oil pump's life.

[d112crzy]

Never had a problem on my engines with the belt being removed. Didn't really notice any extra vibrations either.

[Losiracer2]

I took off my balance shaft belt when doing my Head Gasket. I don't really notice any vibrations at all in the higher RPMs. There is a bit more harshness when idling but that's to be expected. My car is quicker to rev and gets slightly better mileage, maybe 1-2mpg. It really isn't necessary since our engines are balance pretty well from the factory. My guess is that since old granny's buy it instead of young guys, they put that in there.

But taking off the balance shaft belts means 8lbs less of rotating mass, thus less parasitic drag on the engine. Plus, you don't run the risk of walking out your balance shaft seal in front, which, if happens could cause catastrophic engine damage via loss of oil pressure.

[93twodoorLX]

i tend to think that honda engineers are smarter then me. so if they think my engine needs a balance shafts...thats good enough for me. but hey in some cases they do over engineer some things soo i might be wrong. but removing something called a "balance shaft" just doesnt sound right to me.

-sean

[Shadow1]

i tend to think that honda engineers are smarter then me. so if they think my engine needs a balance shafts...thats good enough for me. but hey in some cases they do over engineer some things soo i might be wrong. but removing something called a "balance shaft" just doesnt sound right to me.

-sean

your right tho. but ive taken the balance shaft belt off of both my cars and about to be the 3rd one also. with the 2 it actually rev freer and faster. pick up off the line was much better too. didnt notice any extra vibrations tho. gained a few HP from it too.

[accord2nr81]

no problems here...

[F22Turbo702]

Motor definetly revs quicker with the belt removed. Haven't had any issues. No real noticeable change in vibration.

No balance shafts FTW!

-Kyle

[Night Wolf]

hmmm I might have to do this...

[johnl]

It really isn't necessary since our engines are balance pretty well from the factory.

It doesn't matter how good the primary balance is, it's the secondary imbalances that the balance shaft counteracts. Secondary imbalances are inherant in all straight 4 engines, no amount of crank / flywheel balancing or reciprocating mass equalisation will get rid of it, no matter how well this may be done.

Only by introducing equal but opposite imbalances with a 'balance shaft' (IP Mitsubishi, to whom all other engine manufacurers using this technology pay a fee) can the vibrations caused by secondary imbalance be cancelled out, or at least reduced.

On smaller straight 4s up to about 2Ls the secondary imbalances (and thus vibrations) are not all that great, but the bigger the capacity (typically over 2L) the greater they become. V8s also suffer secondary imbalance, though far less so than a straight 4 (maybe some V8 secondary imbalances 'cancel out' other secondary imbalaces to some degree?).

AFAIK only straight 6 and V12 engines have perfect secondary balance, which is why they tend to be such smooth motors. Even with smaller straight 4s, most manufacturers are likely to use relatively softer engine mounts to mask the secondary imbalance vibration.

Interesting to hear that deleting the BS belt on Accord motors only results in a small increase in vibration (then they are only about 200cc over 2L), but it may depend on just how soft or hard the engine mounts are...

I used to own a Lotus 7 style sports car (not actually a Lotus), fitted with an 1800cc Fiat twin cam mounted in fairly hard non stock mounts (made from spring shackle bushes), and this car definitely vibrated more than most people would want to put up with.

[Losiracer2]

It doesn't matter how good the primary balance is, it's the secondary imbalances that the balance shaft counteracts. Secondary imbalances are inherant in all straight 4 engines, no amount of crank / flywheel balancing or reciprocating mass equalisation will get rid of it, no matter how well this may be done.

Only by introducing equal but opposite imbalances with a 'balance shaft' (IP Mitsubishi, to whom all other engine manufacurers using this technology pay a fee) can the vibrations caused by secondary imbalance be cancelled out, or at least reduced.

On smaller straight 4s up to about 2Ls the secondary imbalances (and thus vibrations) are not all that great, but the bigger the capacity (typically over 2L) the greater they become. V8s also suffer secondary imbalance, though far less so than a straight 4 (maybe some V8 secondary imbalances 'cancel out' other secondary imbalaces to some degree?).

AFAIK only straight 6 and V12 engines have perfect secondary balance, which is why they tend to be such smooth motors. Even with smaller straight 4s, most manufacturers are likely to use relatively softer engine mounts to mask the secondary imbalance vibration.

Interesting to hear that deleting the BS belt on Accord motors only results in a small increase in vibration (then they are only about 200cc over 2L), but it may depend on just how soft or hard the engine mounts are...

I used to own a Lotus 7 style sports car (not actually a Lotus), fitted with an 1800cc Fiat twin cam mounted in fairly hard non stock mounts (made from spring shackle bushes), and this car definitely vibrated more than most people would want to put up with.

yeah i swear, the vibrations are minimal to none. I can't even feel it in my engine anymore, I guess I got used to it. But at WOT, my engine has no vibration whatsoever. I used to feel it through my accel. pedal slightly, but that has changed, remember, I put in a FRESHLY rebuilt cyl. head w/ a 3 angle valve job and new valve stem seals, so that probably needed some time to break in properly.

But after that time has passed, I truly don't notice any vibrations or shuddering, and I even have an ES front Poly mount installed. Steering wheel is shake free, even when A/C is on. My car is an auto as well.

It feels as though there is more torque right in the beginning and throttle response is improved also. Owequitit had his balance shaft belt removed for 10s of thousands of miles before he got his H22 and didn't experience any problems whatsoever.

Its a totally FREE mod, which is a plus. All you'd have to do is remove your upper and lower timing cover, untension the balanceshaft belt and slip it off. You might need to retension your timing belt since the balance shaft and timing belts are connected on one axis as far as tensioning goes. But removal of this belt has no effect on any of the other rotating components. The only thing that changes is the two balance pullies, front and back are no longer being spun, which results in more usable power from what I can feel.

[wed3k]

or just cut that bitch off. ive done timing belt jobs on multiple toyotas and they dont run balance shafts.

[bjaccord]

I've ran my motors three ways, with the shafts working, without the belt and then with the shafts completely removed, and I've never noticed any kind of difference in vibration.
I run solid mounts with delta cams so it inherently has some vibration anyway, but any changes with the balance shafts has never made it any worse.

L8r

[johnl]

My Lotus 7 lookalike had less noticable vibration at higher than lower rpm.

Most karts have single cylinder engines with abysmal balance, and can vibrate your body organs in a most unpleasant manner at low rpm (say on formation laps), but smooth out a lot at higher rpm (and kart engines do rev, mine did 16,000+rpm, and some do as high as 20,000rpm).

[WilliamW]

Now what's involved in everyones removal. Is it just the belt with leaving the actual shaft in? No DIY's and I'd like to know more.

Oh, and johnl, I've had a 1976 Fiat 124 Spyder 5 speed with a 1800cc DOHC engine (if this is the same engine your talking about) and it WAS pretty rough around the edges lol.