need opinions about flywheel wieghts

i am thinking about getting a zipty bolt on fly wheel for my 99 yz400 and just wanted to know how it performs once u get it on, and how hard it is to install. :) any advice would be apreciated

If you do a search on this forum for 'Flywheel Weight' you'll find lot's of info. By the time you get back as far a April 2002 you'll be bored. This topic seems to come up several times each month and the information is mostly repetative.

Here's a website to checkout:


i installed a bolt on 12oz weight on my 426, and its xellent. i ride my bike now 15/50 gearing no problem and the bike never stalls (and if it is its the rider fault)....

just get it...

get the ty davis one - it comes as a kit including everything u just need drill and electricity.....

i dont have much trouble with stalling untill i get to a long steep hill and its hard to hold a steady rpm. i also herd that a flywheel will increase the engine braking? wich is someyhing i havent yet learned to deal very well with yet, only have ridden the bike twice. also how does it effect how fast it revs i like the acceleration but its proness to stall scares me when attempting large hills i curently run 14 49t gearing and would like a higher top speed as i ride in the ls vegas area i checked out the search and did find some info but i need more help. 99yz400 only engine mod white bros muffler any other mods would also be appreciated :)

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