125-200cc Flywheel weight

Got the 2nd ride in on my 12 cr 150. The suspension is an amazing set up for the woods and my weight. I like the power of the motor, but coming off a wr 300, I think that I would like a little more low end. Would a flywheel weight be what I need or can I just change the gearing. If I need a flywheel weight, what size? I am just trying to get this fun bike closer to perfect!

Try 13/52 gearing. I prefer the WR ignition but some like the CR ignition. Go to a 36mm Lectron Carb also.

I know what you mean. As I've just gone to cr ignition from a wr . I think a flywheel weight would be worthwhile.
12 oz or slightly less
I think I'd rather try the 165 first then the wr ignition may be the way to go to smooth it out

There must be something wrong with your bike I have a 2008 CR 125 now a 165 and it is almost imposable to stall.Works great in tight single track.I just raced and finished King of the Motos and I beleive there is no tighter single track out there ,no problem with the stock CR flywheel For KOM I ran 12/52 but for everything else I run 13/52 I have also run 14/52 for some of the faster stuff 13/52 is the best all around
Why weight down the crank it is hard enought for the little bike to pull and now with a weight it will be harder

Ajax/John he wasn't stalling just looking for a little more low end. I think your and Vinduro 13/52 suggestion will help him. I also like Vinduro's suggestion on the Lectron carb. I had the FMF Fatty on my 125 and 144 and it also helped low end. Now if you really want more power skip all the other steps and jump up to the WB165 kit with FMF 200 Fatty (KTM) pipe and metering carb. Then you will then have all the power low-top you will need.

I know that I can go with the 165, but I pretty well blew out the budget going with the 12. It already has the fmf pipe. I do not have an extra $1000, so I was looking for something a little more budget friendly right now. I did not have any problems with the stalling. I would just like a little more pull off the bottom. I was hoping it would make me a better rider compared to the 300 that you can be lazy on. Maybe I just need to ride it more and not be such a puss!

The WR ignition does feel better right at bottom and a bit more over-rev. Weaker mid.
Something that is free and worth trying is moving the bolt on the linkage to the top of the slot to ensure power valves are closing well. This does reduce the top end a bit though from my experience as they do not open as fully.
Also worth testing it the other way as well to see more top end
If you are lucky enough to have Walt do his thing on the power valves it will help too .
I have 52 rear because it was a wr 125 bog machine but now Im not sure it needs it - it does run out of legs very quick and would prefer to go back to 50
One more thing thats free - dont forget to use the clutch - your clutch is your friend
sounds like you may need to adjust to riding it

even as a 125 racing wide open desert I ran 13/52 The bike will not pull a 50 Cheap way to go gear it down

if you want more low-end "power"? : more compression, more pipe, PV timing alteration, porting work, smaller carb,. E- all of the above.

flywheel mass adds inertia, gives it more traction, in the purest sense of the word, may or may not slow the spool-up down. does not add power. it can increase traction.

lower gearing gives it more snap/faster roll-on.

Thanks duke, I think you helped me. I seemed to be loosing traction coming out of corne and up hills, when I got on the trottle. It had plenty of power for me. I just do not want to loose any of the top end.

oh totally go up a couple/few ounces or so if possible for the east coast. when you increase the flywheel mass, spool her up and slip the clutch it glues the back wheel to the ground. slipping the clutch with a lil more spooled up flyhweel mass = supple suspension action (no chain torque lock-out) and wicked good drive. mreeeeeeep! my '09 WR125 outa the box would smoke any 125 moto racer i came across. my wingman has a yz125 last gen, its fast, my 09 WR125 could smoke it, and it didnt even have the cool ignition like the CR does. it also hooked up pretty dang good if i fed it clutch. a couple/few ounces will take away nothing from the top on a well tuned engine. once the intial moment of intertia or whatever its called is overcome and it has the right gearing it's snaps just fine and explodes outa corners better in deep crap cuz again, it has more spinning mass- that = traction. it lugs like a sewing machine too. the only drawback is if you really add a big bunch of flywheel weight is it'll take a milisecond more to come off idle when ya whack it. and its a 125 who rides it there id say a nice compromise would be someaht less than my WR's had it had a lot and didnt have that CR snap/bark thing that sounds so cool, but it hauled balls, and after i got a pipe from Donny down the street it was c-ya mreeeep mreeep! oh crap here i go missing Trigger again thanks alot guys... ...

So whould you say 12oz for east coast ? They run from 6-12 two oz at a time.Was going from put-put to spin. Want to slow that down just a tad.

Does anyone know the weight of the fww on the wr compared to the. I want to go a little heavier, but not the 12 oz. Maybe the wr weight or a little more.

The WR is more than 12oz

I put a 13oz on my cr165 and can barely feel it. Also have a 9oz on my yz250 and its almost unnoticeable.
More is better imo

The wr flywheel is .4kg heavier than cr - 1 lb in old ...