question about ram air ducts

[flickster]

I have a 97 xx that I bought last summer. This bike hasn't run right even before I bought it. A little history on it: It idles fine, i can rev it while sitting in the driveway fine. I can run it in first gear to redline fine. Only when a lot of air starts getting into the airbox does it start sputtering and pausing.

I've put another set of carbs on it, replace the spark plugs, tested as much of the electrical as I could, all produced the same results

I've cleaned the carbs, even tried a dynojet jetkit.

The bike is stock other than the yoshi full exhaust.

So, I was looking at the diagrams on bikebandit and seen on the 98 xx there are ram ducts that connect from the airbox to the front of the bike where the screens are.

My 97 does not have these air ducts. I cut carboard and put under the airbox inlets to kill the forced air from getting into the airbox and the bike runs great like that.

I guess the main question is: does this bike suppose to have ram ducts ??

If so, does anyone have any for sale, I need both the left and right.

Thanks guys for any help

[XXTi]

I don't believe the carb'ed XX's had ram air to the airbox. The ducts go to the oil cooler IIRC.

[blackhawkxx]

Only FI bikes have ram air. I don't understand, if your bike runs better with the flow of air blocked off, why would you want to ram air into the air box by putting in air ducts?

[sykotek-xx]

Weird problem. Perhaps you are missing some of the ductwork on your 97, and it is causing some weird turbulence that is starving the airbox at speed.

On the 97-98, the front ducts force air through the oil cooler. They should have nothing to do with induction or your airbox. On 99 and up, they are a sealed ram air system that go directly to the airbox.

[typicalmale1978]

I have a '97 as well, and there are in fact two (not ram air) ducts, running from the air box a little past the sides of the frame and tucked under the side panels on the fairings. I guess the part I don't understand about your problem is the fact that with the fairing on the bike air could not go directly into the airbox even without the ducts. If your bike is naked as is mine, then yes you will have to create two air diverters of some sort for the bike to run properly. I used a piece of sheetmetal from Lowes to make mine and painted them black and you can't even tell they are there. Hope that helps ya some.

[flickster]

thanks for all the replies.

the reason i say the forced air is causing problems is this: I can be riding down the interstate at 80mph and the bike will be running really bad, cutting out, spitting, no power. I can tuck in behind a transfer truck and immediatly the bike gains a lot of power and will run just like it should. I assume the truck is blocking that forced air from getting into the airbox.

Right now, air can get into the airbox from where the radiators are located. there is a lot of air coming through that area at high speeds. Whereas the ram ducts would restrict some of that huge amount of air flow.

Here again, these are just my opinions, i'm no expert (thats why i'm here :icon_wall: )

I'm banging my head against the wall trying to figure this problem out. The honda shop says the carbs need cleaning and the plugs need changing ( they want $400 - $500 for that job) but i've done that very carefully.

oh well, keep the ideas comin, i sure do appreciate it.

flickster

[typicalmale1978]

Well it sounds like you have done enough experimenting to have pinpointed the problem. Just make a couple air deflectors out of something more durable then cardboard -lol- and save yourself $500.