zagger Posted October 17, 2015 Share #26 Posted October 17, 2015 @zagger What are you using for intakes stacks? Each carb has a thin wall aluminum tube sticking straight upward with a pod type air filter on the end. Each tube connects to a carb using a short rubber sleeve with hose clamps. The intake filters aren't protected from rain, except when the bike is moving where the frame, electronics, etc. tend to keep water off them. I cover them with plastic cups if I have to park in the rain for more than a short time. My carbs are a little higher than normal because I have Vboost valves mounted under them (from a Vmax). zag Link to comment Share on other sites More sharing options...
Larry1963 Posted October 17, 2015 Share #27 Posted October 17, 2015 Funny how the law works, at times the obvious innocent are the ones in trouble. Link to comment Share on other sites More sharing options...
VerntureVet Posted October 17, 2015 Author Share #28 Posted October 17, 2015 You didn't have issues with the carbs tripping out? Every time I try to take off even just my Airbox cover my carbs trow fits. Link to comment Share on other sites More sharing options...
zagger Posted October 17, 2015 Share #29 Posted October 17, 2015 You didn't have issues with the carbs tripping out? Every time I try to take off even just my Airbox cover my carbs trow fits. It's been eight years, so I hope I'm remembering correctly: Each inlet has a machined plate (like a metal washer) with a 1 inch diameter hole to act as a flow restriction. I did calculations on the airflow restriction created by the stock airbox and then calculated what was needed to produce a similar restriction for each cylinder. It should also be possible to measure the pressure drop across the airbox inlet at various rpm's and recreate the same pressure drop with whatever you want to use as the air inlet/filter arrangement. Measured pressure drops are probably going to be more accurate than pencil and paper calculations. I also added Vboost valves (from a Vmax) and found that leaving these valves slightly open improves the engine performance a little bit - not a huge effect, but noticeable via my "seat of the pants dyno". Of course, since these valves allow a single cylinder to breathe through two carbs, they also affect the airflow through each carb and affect the pressure drop across the machined orifice. All this just to ditch the airbox! zag Link to comment Share on other sites More sharing options...
VerntureVet Posted October 17, 2015 Author Share #30 Posted October 17, 2015 Each inlet has a machined plate (like a metal washer) What I was trying to do was make a two 1.5in pipe inlets that stick out the side of the bike and point forward scooping air into a MUCH slimmer airbox that I made from copper plate. I used 2 of the round 2in filters on the inside of the box and then mounted that onto the new box I made. for the venturis I just used a copper 90s and pointed them all backwards where the air comes in. I spent the better part of 2 weeks with fans and a smoke streamer getting the flow right. Needless to say I was disappointed it made the carbs have fits. I never even thought to consider the restriction. Thanks Link to comment Share on other sites More sharing options...
zagger Posted October 17, 2015 Share #31 Posted October 17, 2015 (edited) VerntureVet, I pulled off one of the pod filters to show you the flow restrictor - basically a washer with a 1 inch hole. I guess my memory isn't completely shot. zag PS I'm giving up trying to figure out what is shown in your sig pic. Wanna give me a clue? Thanks. Edited October 17, 2015 by zagger Link to comment Share on other sites More sharing options...
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