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Mellowing the powerband (calming the beast)?

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Just picked up a 1996 WR 250 (same engine as a 94' YZ). Well it has a pretty abrubt mid-rane punch. Runs strong and clean so jetting seems in the ballpark. I plan on adding a 13oz flywheel weight. I came across the G2 throttle tamer and wonder if its worth the $. What else can smooth the powerband? Reeds possibly? Any thoughts, tips or advice would be great. Thanks.

Edited by keenxxx

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Just picked up a 1996 WR 250 (same engine as a 94' YZ). Well it has a pretty abrubt mid-rane punch. Runs strong and clean so jetting seems in the ballpark. I plan on adding a 13oz flywheel weight. I came across the G2 throttle tamer and wonder if its worth the $. What else can smooth the powerband? Reeds possibly? Any thoughts, tips or advice would be great. Thanks.

Power blades help. It beefs up the bottom so the hit is not as noticable. Much smoother power band.

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I found the G2 very useful for my woodsified KTM SX.  However, before you throw all these bolt on parts at your bike, a less expensive and simpler alternative might be to have Gorr or Pro Circuit (or another reputable tuner) port your cylinder for the powerband you want.

Edited by rpt50

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You could run taller gearing (smaller rear sprocket) to stretch out the gear ratios to make the power delivery not so 'peaky'

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Jetting. You could try going one clip richer on the needle position, and if that's too blubbery, try a leaner main. So you get more docile roll on torque but keep the same top end power. An experiment.

Fresh muffler packing also smooths it out a bit and makes response more consistent to throttle usage.

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Adjusting your ignition timing will help "Calm the beast", or wake it up, depending on which you prefer!!!

I spoke with a fellow WR owner and he did adjust his timing. I'll have to check the Yamaha owners manual for spec's and procedures.

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This is the first 2 stroke I have owned since 1990. In the past I just rode my bikes I never had the $ or thought to modify a power band. I'd like to get the most bang from my buck. A fww, throttle tune, pipe etc. is going to add up quick. Thoughts as to which should be the first most beneficial bolt on mod? I will probably do the free stuff jetting/ timing as well Thanks.

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Eric Gorr's book mentions using the 4 ball governor in that year motor vs the 5 ball. Install part # 20 and throw out the extra ball

 

I have the same motor and am planing on doing this mod. There is less of a power band "hit" with the later year YZ's

 

GOVERNOR.png

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This is the first 2 stroke I have owned since 1990. In the past I just rode my bikes I never had the $ or thought to modify a power band. I'd like to get the most bang from my buck. A fww, throttle tune, pipe etc. is going to add up quick. Thoughts as to which should be the first most beneficial bolt on mod? I will probably do the free stuff jetting/ timing as well Thanks.

Eric Gorr porting is $225 for a 250, for whatever powerband you want (any color too, ha!), which is not much more than a G2 throttle cam ($90) and FWW ($105).  Of course, neither of the latter is actually going to redistribute power in the rpm range--it is just going to make the hit easier to manage.  The FWW does have the nice benefit or reducing stalls, if that is a concern for you.  A gnarly pipe will redistribute power, but the cost (new) is pretty comparable to porting as well. 

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Eric Gorr's book mentions using the 4 ball governor in that year motor vs the 5 ball. Install part # 20 and throw out the extra ball

 

I have the same motor and am planing on doing this mod. There is less of a power band "hit" with the later year YZ's

 

GOVERNOR.png

Interesting must keep the exhaust valve closed longer? Can this part be replaced w/ o removing the case cover?

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Eric Gorr porting is $225 for a 250, for whatever powerband you want (any color too, ha!), which is not much more than a G2 throttle cam ($90) and FWW ($105).  Of course, neither of the latter is actually going to redistribute power in the rpm range--it is just going to make the hit easier to manage.  The FWW does have the nice benefit or reducing stalls, if that is a concern for you.  A gnarly pipe will redistribute power, but the cost (new) is pretty comparable to porting as well.

Porting sounds key but I'd rather try to keep from a major tear down. The fww seems beneficial anyway . Not quite sold on throttle tube just seems like I may not have enough power @ times w/o rolling my wrist.

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I would imagine the Fly Wheel weight and gearing would be the easiest ways to tame the power band hit. The Fly Wheel Weight will also help prevent stalling which a lot of guys like for woods riding.

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Milling heads down a little can also help with the low end grunt. I milled .025 off my yz head and ran a race gas mix just because. You can also buy a spare used head for cheap off ebay, that way u can go back to stock easy or experiment more.

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