ram air modifications

FREEMO · Post by **FREEMO** » Fri May 29, 2009 11:29 pm

hi ,everyone new on here ,have just bought a kris for the track,been stood awhile,it has some kind of ramair system fitted ,two bits of hoover pipe from front to front of airbox lid cut and no innards in it except a thin sliver of foam,have looked at mj,s information but need someone to explain in simple terms for an ageing racer like me to understand,as i was under the impression that ram air only worked on /in a closed airbox with still air if any one can shed some light, as iv,e got a good mind just to rip it out freemo.

JanBros · Post by **JanBros** » Fri May 29, 2009 11:50 pm

ram air can only work if the carb's float bowl has the same pressure as the airbox. so you can do 2 things : mount the carbs inside the airbox, or have some tubes that go from the airbox to the overflow-things on your carbs.
if neither off the 2 are present, than it won't work, it will even do more harm.

what will work is use the tubes from the front off the bike to the airbox to get cold air in it, rather than heated air from the engine/radiator. cold air contains more molecules oxygen than hot air. so make an extra opening in the box so it won't be pressurised and you can benefit from the cold air.

and my opinion : it's pretty useless to put all that effort and energy in creating a ram-airbox. below 100km/h there is absolutly no gain, and real gain can olny be achieved above 200km/h, speeds we will hardly get on our KR's.

FREEMO · Post by **FREEMO** » Sat May 30, 2009 12:15 am

thanks jan bros that helps alot can understand that info no prob,judging by what you have said i think i will rip it out anyway ,thanks again regards mark freemo.

the-elf · Post by **the-elf** » Sun May 31, 2009 2:22 pm

As Jan said, It sounds like you have a cold air feed, rather than an Ram air. If its Ram air then the rear inlets will be blocked to seal the box and the pipes from the carbs will have been feed back into the airbox to equalise the pressure between the box and the carbs.

Doing a full ramair box isn't that hard, and it does benifit the KR as a standard airbox is really too small. Most people try to enlarge them and atleast feed a supply of cold air into it.