lightened flywheel

[jimmyjam400ex]

anyone hav a lightened flywheel im thinking about doin this and i wanna hear some opinions on it i ride trails fields and back dirt roads and i would like it to rev a little quicker and be a little snappier

[bherriman]

This is just my opinion but go with something like a sparks advance key ( +3 or +6 degree) this will do the trick to improving your throttle response and help it be " snappier". Maybe its just me but I wouldn't trust a lightened flywheel

[PaRedneckRiders]

Ok well i was also thinking about shaving my flywheel but decided not 2

Its not gona make it any faster, if anything it would be slower

I will rev quicker and that could be nice, this was the hole reason i considered doing it

But with less reotating mass inside the motor it will have more of a tendancy to stall if your laying on the throttle and come into a hard turn and let off the gas

So it has both its pros and cons

U would be better off with just an advanced timing key

[Thumpin440ex]

Does this key really make a diff in the performance of the bike, forgive the thread jack. I have heard about this but have not read into it. So the key changes what timing? the cam timing or the ignition timing?? And will it allow the engine to still pull hard and the same all the way to redline??

John

[BamBam21]

I've lightened my flywheel a considerable amount and I've had not one problem stalling or any other CON's, it revs a whole lot faster and SEEMS faster.

BB

[BamBam21]

oh yea, the sparks key advances ignition timing.

[jimmyjam400ex]

how much did you lighten yours and what kind of riding do you do
i dont see how taking out 6-8 oz could make it stall so easy if like 16 oz is takin out for the kickstart conversion and it is suppposed to run awsome after that i just dont have the money for the conversion but i would like it to rev more like an xr i rode one the other day and wow wat a difference in the motor and it was completely stock i want mine to rev a lil more like that

[BamBam21]

I dont remember what I took off of it, but I think it was about 16-18 oz off the flywheel itself, This was not including the starter gear/clutch assembly. You cant take that much off if you're keeping the electric start, probably more like 10-12 oz. I ride on mostly trails and pits, hill climbing, nothing crazy.

BB

[jimmyjam400ex]

i think i should be ok taking off like 7 oz i dont wanna take away too much momentum if u use urs for hillclimbs and trails nd it is still fine i should b ok if not i am only using my spare flywheel so i can always put the stock one back on

[brewster426]

less rotating weight=more power..to an extent.

[BamBam21]

Originally posted by brewster426
less rotating weight=more power..to an extent.

Actually you may gain a little HP, the advantage is the engine will accelerate quicker, I build V8 racing engines for a living and we have lightened rotating assemblies a considerable amount and see very little hp diff.

Thanks BB

[brewster426]

it only makes sense that a lighter rotating assembly makes more horsepower. its the same as putting a heavy tire on instead of a lighter tire (or wheel). with something that only makes small power over something that makes a lot more power the lighter flywheel has got to be the ticket to free hp. there is a thread about a guy taking like 2 pounds off the flyweel that made 40% more power on the dyno. but i raced gokarts for about 6 years and i know that if you put the smaller 3hp flywheel on a 5hp design block (the 3 hp fw is a WHOLE lot smaller makes a significant amount more hp on the dyno, but you have to be careful putting the shaved flywheel on it because at high rpms in will come apart, hense the billet flywheel wthat will not come apart. i dont mean to be a smart *****, correct me if im wrong

[jimmyjam400ex]

i think im gonna give it a try it the flywheels hold together when they r lightened for the kickstart conversion the should be fine with about 8 oz of of it i am really excited to see how it works i just need to call some machine shops to see what kind of prices and how far itll set me back

[brewster426]

balancing it i think would be the tricky part

[jimmyjam400ex]

im planin on takin it to a really good machinst around here named louis who is supposed to be one of the best guys around here and no one can touch the quality of his work and from what ive heard this should be a fairly simple job for him