Power band question

[mmz77]

Just got a quick question. I was wondering if the older bikes that didn't have power valves would still have a power band like the newer two strokes that do. I am just curious.

P.S. Scared the crap out of me today when I hit the power band from a patch of grass to dirt and the front wheel shot up :boss: . I guess I have to get used to this lol.

 

[76GMC1500]

Yes, the power band just the range at which the ports and expansion chamber operate most efficiently at. A power valve broadens the power band. Power valves can actually tame the hit.

 

[rmc_olderthandirt]

Yes, older bike have a power band, and without the powervalve it would be a narrower band.

Rod

 

[84cr125]

ya the older bikes do have a powernd. i should know, cuz i have one. Once she hits, she hits hard and fast.

Ive got one of Hondas first Power Valves, they called it the ATAC.(Automatic Torque Amplification Chamber). it was built to help the woes in the bottom end and also help the transition throughout the rpm range without harming the top end power.

 

[keip82]

which is better with or without power vavle

 

[mmz77]

I would say with...

 

[76GMC1500]

Definately with. It lets you run more aggresive porting for more peak horsepower, but still have a broad and useable power band. Power valves also tame the hit down to give you better control.

 

[MikeT]

Very good answers guys. I can't add anything else.