Lightened flywheel...good for me?

[Glamis400ex]

Would a lightened flywheel do me better in the sand dunes or make things worse for climbing etc??? Just curious because really, there's nothing wrong with your engine spinning a tad faster right??

Mods to my 400ex are in my sig,

Thanks.

Glamis

[MarkyNark]

There will be some different opinions, but I've had good luck with mine. Basically, the lightened flywheel will allow it to rev quicker, but the flip side of that is that it wont maintain low RPM revs as easy - you'll have to do that more with the throttle. If you dont, it will simply kill the motor. Thats the theory, its its been pretty true for me.

Its really not much of a disadvantage, one that can easily be taken care of with a higher compression piston, which will gain you more torque and horsepower. Of course with that option, you'll have to increase your octane.

Marky

I have one on my quad, good for mx but sucky for trails. and I have to be way quicker shifting because the gears fly by.

[Glamis400ex]

OK, well I do have a hi comp 11:1 piston (416) and I do mix 110 VP with 91 gas which gives me around 100+- octane.

So, what will the experience be like? Will it take off quicker or what? I'm not sure I understand what it will feel like. Possible like a 2 stroke? Do you actually go thru the gears faster?

Glamis

do you have a rev box?
because if not then it is a must for a liteined flywheel.

it is nothing like a 2 smoke.

but with my litened flywheel the quad revs so fast that the only way that I can really keep up with shifting is if I just rev the piss out of it in every gear.

it is hard to explain. Loads of power as long as your on the gas, but if you let of it shure can stall in a hurry. it is like the engine has less mass to it. letting it change rpms a lot faster. so it can rev up faster or rev doun to stall faster, if that makes any scence.

[Glamis400ex]

I do have a WB rev box, but I choose not to use it. I like the feel of the stocker with my mods.

So if it revs quicker, you get into the meat of the powerband faster? You can stab the throttle and not have any hesitation, say, if you're in 4th, but NEED to be in 3rd?

The reason I'm asking is because I saw a few on Ebay. One was used and had 7 oz. taken off and then there is a new TC with 8 oz. taken off.

How hard is it to change the wheel? Do I need any special tools?

Sorry for all the dumb questions.

Glamis

it is really imposible to explain... but ppl do it so it must be good.. lol


you will need a puller to get the flywheel off. and a good one too.

how much are thoes used flywheels going for? I bought a stock one with a cupple gears for 40$.

[Glamis400ex]

The used on w/ 7 oz. off was $60 and the new TC w/ 8 oz. off is $100.

Glamis

[cals400ex]

i have one lightened by gt thunder and my bike was quicker when dragging with the stock one on.

[Rico]

I've had one on mine for 5 years now and have no complaints. They work great if you know how to ride hard but if you poke around on the trails you won't like it.

I don't have problems stalling my bike either. Keep the revs up and learn to feather the clutch and you'll be a speed demon.

[cals400ex]

i say if the price is right go ahead and get one. one thing i want you to do though is keep your stock one and find a buddy with a bike that is about the same speed as yours. this is what i did. i have a buddy that i would drag race on a weekly basis. we would go on pavement so traction wasn't as issue. we raced multiple times before and after in installed the flywheel. i was simply slower with the lightened one on. i didn't have any stalling issues with mine either. i took the lightened on off and put the stock one back on. i was back to beating my buddy every time again. not sure what the problem was but i did not have good luck. in fact, it was horrible luck. i just love to spend money to make my bike slower. :eek:

i would be curious in your results if you can find another bike that runs very similar to yours.

[Rico]

Originally posted by cals400ex
i say if the price is right go ahead and get one. one thing i want you to do though is keep your stock one and find a buddy with a bike that is about the same speed as yours. this is what i did. i have a buddy that i would drag race on a weekly basis. we would go on pavement so traction wasn't as issue. we raced multiple times before and after in installed the flywheel. i was simply slower with the lightened one on. i didn't have any stalling issues with mine either. i took the lightened on off and put the stock one back on. i was back to beating my buddy every time again. not sure what the problem was but i did not have good luck. in fact, it was horrible luck. i just love to spend money to make my bike slower. :eek:

i would be curious in your results if you can find another bike that runs very similar to yours.

Were you slower topped out in 5th or from the very start???

[cals400ex]

i was not slower in 1st gear, well not anything that i could notice anyways. i noticed it in 2nd gear a little. near the upper rpm band in 2nd i could notice. then it got a little worse as i went through the higher gears. from 2nd-4th gear, i noticed around a 3 bike length loss when dragging. i did notice that the bike did not want to rev quite as high. it wasn't very noticable but i could tell. if i was in the dirt or on a track i probably wouldn't be able to tell. but since we race on pavement a lot, i could get shift points down pretty well. it just didn't want to rev as high. i would try to keep it revving and it wouldn't go. i then tried shifting a little earlier and that still didn't help me when dragging. i would say the instant throttle response at LOW rpms was probably better but i really didn't care how it performed at low rpms. i had laz lighten my flywheel and i know he doesn't take off as much as other builders. but still that shouldn't matter. he told me he recommended a stock weight flywheel but i went ahead and got one lightened to try it out. thank goodness i kept my stock one though. to tell you the truth, from the seat of the pants there wasn't much difference at all. i was shocked because i didn't think i lost that much until i raced my buddy. it felt like i was around 1 bike length slower but it was hard to tell unless i was on pavement where everything was smooth and i could clearly feel the powerband. maybe i should have sent the flywheel to trailtech to get it balanced. maybe it wasn't perfectly balanced. but at that time i had enough with it because i bought another flywheel and then paid $50 to get it lightened so i didn't want to spend more on it.