GNR101 Posted December 19, 2009 Report Share Posted December 19, 2009 so no1 had tryed the VF3 and chariot reeds head to head? i would be intrested in the findings Quote Link to comment Share on other sites More sharing options...
PassionRE Posted December 26, 2009 Report Share Posted December 26, 2009 (edited) Not to add fuel to any fire, I thought it might interest viewers to learn a few cold hard facts about reed valves. If nothing else it might give a few of you ideas in how to tune a little extra power out of your machine, regardless of what reeds you are currently using. First I'll address a few statements made throughout this post: 1) "No one reed design will be best in every engine configuration"...this is a cold hard fact. With all the options available in cylinder porting, monoblocks, stroker cranks etc. this is definately the case. 2)" The mathematical formula doesn't exist in reed design"..... not true. Like any machine that operates within the laws of physics on planet earth, with given properties and characteristics of those said properties, its performance capability can be calculated on any engine configuration with amazing accuracy. For broad rpm range efficiency it becomes a little tricky, but for all out performance as in drag race engines, it's alot easier. Tools do exist for this design process, some commercially available, some privately held. Certainly not rocket science, but it might seem so if your trying to develop or tune reeds without the use of them. Unlike mechanical valves as in 4 strokes, a reed valve is a interactive valve with a direct relationship to the engine its mounted to. In addition to this, its performance will also be affected by the expansion chamber and tuned resonance of the intake manifold between the reed tip and carb entrance as well. Generally speaking, the better the pipe, the better the reed will perform unless its extremely undersized in cage area or reed lift area. Also, if the reed configuration's natural frequency is out of range, high or low, performance will be deminished. If a reed's natural frequency falls well below the engines natural frequency at rated peak HP rpm bottom end power at lower rpm ranges can actually be improved, but at the cost of high rpm reed stability resulting in power loss at high rpm and almost certain reed damage. If the reeds natural frequency is too far out of range on the high side, bottom end power will suffer as a result and if even higher yet, top end power as well. A reeds natural frequency is determined by reed compostion material, thickness and stiffness of this material, and clamped length of the reed. In reed design a few questions have to be answered upfront. 1) What is the expected performance of the engine design itself? 2) At what rpm is this engine going to produce this level? 3) what displacement and primary compression ratio are we using? 4) Is my carb big enough for this goal? OK...the reed valve itself....the 3 must haves to get there. 1) cage area...has to be big enough to flow the required amount of air to meet the performance level. 2) reed lift area.... this is the interactive process at its finest. Will these reeds open up enough to allow the required air requirements for my engine design? 3)...And better yet, will they be operating at a natural frequency that wont cause tuning problems? HUGE importance, this is what seperates a good reed from a bad one. Other variables exist as well, but these are the big ones. You can mess up your design in other areas and still meet your goals, mess these up and you'll never get there. A flow bench can be a good tool to use if you know the max values of lift area a engine is capable of producing. But even then you are just testing the cage and cfm capability at a given reed lift area. If you've based your lift area on the actual value your good to go as long as you know the natural frequency of the reed and it matches your engines peak rated HP rpm, if not, all bets are off...this goes back to the no one reed is best on all engines statement I reffered to earlier. ALL OUT HP CAPABILITY... a subject a few of you might be interested in. Pay particular attention to REED LIFT AREA and NATURAL FREQUENCY. Most reed cages themselves are capable of more than you need unless your trying to exceed 85RWHP...even the stock Yamaha cages can do this, although the reed choice itself is just mathematically disasterous. For you guys with big stroker motors, Cubs, etc. Youll need more than 4 entrance ports per reed valve to massage out the power your looking for unless you are going to totally redesign any reed valve I'm aware of currently being marketed. Im not familiar with Chariots lift area or natural frequency capabilitys, but will be more than happy to calculate it if anyone will send me a few specs. A side note, VF3's are capable of 120RWHP, maybe more depending on the pipe effects due to the pipe design itself and how it reacts to the given transfer duration.....Jim Edited December 26, 2009 by PassionRE Quote Link to comment Share on other sites More sharing options...
MikeNick Posted December 26, 2009 Author Report Share Posted December 26, 2009 DAMN!!! That was a very interesting post JIM....... Quote Link to comment Share on other sites More sharing options...
banshee332 Posted December 31, 2009 Report Share Posted December 31, 2009 (edited) Damn Jim very good info, glad to see you back on the forus Edited December 31, 2009 by banshee332 Quote Link to comment Share on other sites More sharing options...
rb0804 Posted January 4, 2010 Report Share Posted January 4, 2010 A side note, VF3's are capable of 120RWHP, maybe more depending on the pipe effects due to the pipe design itself and how it reacts to the given transfer duration.....Jim What about the VF2's? Quote Link to comment Share on other sites More sharing options...
cj350banshee Posted January 6, 2010 Report Share Posted January 6, 2010 Here we go again............... he used a oscillating flow bench designed by Fig Newton, model #356-niner007.. It flows 6 millions pixels per linear ft. But.. it didn't pass the Firehead Technical inspection... So its not Firehead compliant. "LMAO"!!!!! Quote Link to comment Share on other sites More sharing options...
camatv Posted January 7, 2010 Report Share Posted January 7, 2010 (edited) the ole blaster cage trick thats and OLD one for sure. i have a set of boyesen's v-3's, FMF's and the stockers with port work and boyesen 2 stage reeds. the boyesens if they are like the ones i have and used in the past fit in the stock boots they would take a lot of work to match a larger carb but i think they create a lot of velocity through them but also restrict flow on larger ported engines.. BUT there are also a lot of other issues with them that i think hurts them. if i could find a set of reeds that can extended down to the edges of the cage i think i could fix one of the issues.. i really like the stockers with modded cages and boyesen 2 stage reeds.. between those and the v-3's i cannot "feel" a difference in my lil 350 engines i did put a set of v-3's i sold in a relatively stock bike and it did make a HUGE difference in the way it ran. i was really impressed. in my cheetas i have been using the cr250 reed cages with a lil twist on the type of petals. i have more of a flow on the bottom petals than the top i thinks its helping direct more of the shot down the boost ports and intot he bottom of the jugg.. FIREHOUSE i'd love to hear of your testing of differnt reeds in the 4 mill 65/68mm motors that you didnt really get into. . i dont have any official test equipment just good ole put it in, tune it, race it testing.. i'm thinking of dooing some "testing" with the cages i have now i also have a set of stockers i am going to set up with the carbon single boyesen petals available and see how they feel i have a lil gunie pig banshee that a pretty basic bike t-5's mild porting pwm carbs, head, stuff like that i'm going to swap out all the reeds and see which one seems to run the best then i am going to try and "fix" the boyesen's and see how that goes.. i will say this. chariot is good about "fixing" problems that they encounter. like the bigger nuts deals on their one piece heads with removeable domes. and also the fact they they were willing to desing a high hp banshee head due to some other issue's they had. i respect them for that. it shows a lot to be willing to improve a product and help "fix" problems.. they make some neat stuff for the cheeta's. didnt know they made anything for the tri-z's.. thats a nice tri-z by the way. I got a chance to reseal the engine in one of those just the other day that motor i feel has a LOT of potential. i think its a better design than the honda's 250r if the z had as much aftermarket development behind it as the ole 250r does i think it might be a lot better off. the crank is nicely balanced and light with out a balancer in the engine, to rob HP the clutch basket is big and nicely built and there are weight savings in the motor that yamaha is famos for all over the place. wish they would have put some of that "tech" into the banshee when they could have. Edited January 7, 2010 by camatv Quote Link to comment Share on other sites More sharing options...
chillls Posted February 2, 2011 Report Share Posted February 2, 2011 WOW! this is some good reading. Quote Link to comment Share on other sites More sharing options...
duramaxsmoke Posted January 2, 2012 Report Share Posted January 2, 2012 whats the price difference between the 2 for the power difference Quote Link to comment Share on other sites More sharing options...
sycoticbanshee00 Posted March 28, 2014 Report Share Posted March 28, 2014 The revival! So I'm currently running these chariot reed cages on my stock cylinder 4 mill. Would it be better to upgrade to the vforce 4? Quote Link to comment Share on other sites More sharing options...
WINDYCITYJOHN400 Posted March 28, 2014 Report Share Posted March 28, 2014 In that long post CAMATV made, he referenced that the modded reeds felt the same as his V3's. 4's have clearly tested better than not only standard 3's, but even better than modded 3's. So YES......4's will be an upgrade. When you do, depending on your current tune, you should go up one size on your pilot. Quote Link to comment Share on other sites More sharing options...
shanYE west Posted March 28, 2014 Report Share Posted March 28, 2014 the better question is.. is it worth it.. Depending on his motor configuration, he might see minimal.. if any gain. I could understand if he was coming from stock cages/reeds the gains would be there to justify the $200. But not knowing his motor setup and riding style.. the $200 could be better spent elsewhere. 1 Quote Link to comment Share on other sites More sharing options...
sycoticbanshee00 Posted March 30, 2014 Report Share Posted March 30, 2014 My setup is pretty much your dune ported 4mm on stock carbs, shearer sb. I weigh over 250 and I mostly drag race and occasionally dune also. Just wondering if these vf4 will actually make my bike that much faster that it will change the outcome of a race? I like these chariot cages, they work. Quote Link to comment Share on other sites More sharing options...
sprinklerman Posted March 30, 2014 Report Share Posted March 30, 2014 My setup is pretty much your dune ported 4mm on stock carbs, shearer sb. I weigh over 250 and I mostly drag race and occasionally dune also. Just wondering if these vf4 will actually make my bike that much faster that it will change the outcome of a race? I like these chariot cages, they work.No. chariot to V4's won't make enough power to win a race you would have lost due to HP...All things equal of course. Sent from a van down by the river Quote Link to comment Share on other sites More sharing options...
sycoticbanshee00 Posted March 30, 2014 Report Share Posted March 30, 2014 (edited) Ahhh ok. I'll just keep my chariots and spend my money elsewhere. Edited March 30, 2014 by sycoticbanshee00 Quote Link to comment Share on other sites More sharing options...
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