Counter balencer removal?

I was wondering if anyone has completely removed their counter balencer from their 400/426. I've got the knock again and I think it's that darn key again on my 00/426. Would there be a wear issue on the bearings/piston? It would obviously vibrate more. Couldn't be worse than my old cr500 though.

Any comments or thoughts would be helpful.



As a very general rule, 4 strokes vibrate more than 2 strokes of similar displacement (without counterbalancers). In addition 4 stroke vibration is affected by the engine firing every other stroke, changing the vibration pattern.

Removing a counterbalancer will result in severe vibration, as the crankshaft is balanced diffrently in a counterbalanced engine. If you plan to remove the counterbalancer have the crankshaft balanced to somwhere around a 50% to 54% balance factor. It is likely nowhere near that now.

As for the vibration level, it will likely be worse than the CR500, even if the crank is properly balanced.


Thanks for your .02 Scott,

Yea, I thought it would probably be a bad idea, but it's a pain worring about when the next key is going to wear out and trying to decide if that knock in the engine is a bearing or that rotten c/b key again.


Are you saying you want to run w/out the CB?

Prior arguments notwithstanding you should realize that the CB shaft drives the water pump, so we are talking major engineering hurdle...

Otherwise to remove the CB you need to remove the nut holding the gear from the clutch side, then remove the flywheel and it slides out on that side.

Oh, I almost forgot to mention:


Thank you.

My '00 has many races and many many practices on it and the engine has never given me a hint of trouble and it is still very quiet mechanically. Did I just happen to get a "good one"? Or, did Yamaha fix the counter balancer before I got mine? I keep waiting to hear that tattletale knocking noise but it's still very smooth and quiet. The only trouble I've ever had was the clutch grabbiness that was cured with a Hinson basket and acquiring the habit of holding in my clutch lever for about 20 seconds before engaging 1st gear. After dialing in the carb, the bike has been perfect.

Yeah, bin laden's mother drank the milk from a camel bitten by a flea that once sucked blood from a rabid sand rat!!! ALLAH SUCKS!

[This message has been edited by Boit (edited September 13, 2001).]

Hi Hick and Boit.

I soppose if I had been thinking when I posted the question I wouldn't have asked. I forgot about the water pump. Duh? And, I agree. A very big stick!

Boit, if you have an 01 my understanding is that Yamaha fixed the problem by going to a spline instead of a keyway. My friend rides his 00 twice as much as I do and he hasn't had the problem yet. Maybe I need to ride with earplugs.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now