Lately, I have been thinking about different weighs to save weight. Although I think I might have an idea, I wanted to come here, to the true experts of the industry, and get your opinions. Additionally, I am not sure whether or not this has been done before, but if it has, please excuse my ignorance. Anyways, allow me to get to the question.... sorry for the rambling... What if we removed the balancer shaft and all associated gears and materials? I understand that if this was done then the engine would vibrate like crazy... but why not just balance the crank to compensate? It appears to my untrained mind... that this would cut down on the rotating mass of the engine and not only deccrease the weight but increase the horsepower of the engine as well... Maybe I am crazy and maybe this has already been done before. I just thought I would throw the idea out to you guys and get your opinions....

And, before someone says that I should go to the gym if I want to save weight... let me just say, I do go to the gym and I am 5'8" 150 pounds soaking wet.

I understand some motorcrosser do it.

it would work but i would thimk the reliability would be less because you would turn the motor in to a race on sunday type. some motors need the rotating mass and without it you might not be able to compensate for bearings and improperly casted cases.the crank is not a problem , also i think only 2-stroke motocrossers use this tactic because they have way less rotating mass anyway.

I don't know if it would work.

I'm sure I would be better off just saying "NO" to chilidogs and cheese fries for lunch. (you can actually feel your heart slow down when you eat)

Race

that weight helps in traction, or you'll spin your tire everywhere...plus it gets rid of a crap load of engine breaking...If you want more snap and less weight you can reduce that weight of the flywheel and balancer, but I think you should look elsewhere for lighter weight. By the way go to the gym...haha, just playing. Keep us informed if you get other good ideas

At 13,500 RPM you'd vibrate every bolt on that bike out. Not to mention the aforementioned traction issues. And the YZF's flywheel is so light as it is, if you think it's easy to stall now, WOW would it be bad then. If you ever lugged it that thing would buck like crazy. Not a good idea. Take Tim Ferry's route and get rid of 5th gear if you're gonna pull something out of the cases.

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This is something I would like to do but instead of 5th I'd like to get rid of first. First on my 250F is just there to piss me off on the track. Wonder what the chances are of Yamaha sending me an experimental 4 sp so I can test it for them??? All I need are the gears, I can put them in.

heres acouple of ideas to save weight that i have found that it works but sometimes its a little expensive.

Titanium screw kit- takes every screw out of your bike and replaces it with a titanium screw.
Lighter exhaust- duh
Lighter flywheel- duh
Change engine and clutch covers- carbon fiber is the lightest
Lighter swingarm- $$$
and others that i can't think of right now.

some of these mods are very costly and probly aren't worth all the $$$ but if you really want a light bike i suggest these mods.

Take off rear disc guard, take off rear caliper guard, take of plastic fork protector guides, take off cheesy plastic countershaft sprocket cover and just leave the aluminum case saver on. Oh yeah,the bolts that hold on the rear caliper guard will be needed to hold the aluminum casesaver on. These are shorter than the stupid phillips head screws that hold the plastic cover on. Taking these parts off won't take off that much poundage, but remember ounces eventually add up to lbs.