J-Madd Posted January 29, 2010 Report Share Posted January 29, 2010 Lets just posts the fastest radar runs with each set of carbs. I have a 4mill stroker/stock cyl, on stock carbs running nice, I swapped out to 35 PWK's and didnt gain a .1mph. Stayed at exactly the same mph. I then tried a set of 39's and guess what same shiet. The only difference is that with the big carbs I can only run for 1/3 of the time due to gas consumption. All tests were done in a 1/4 mile That's probably because your still reaching the same max RPM with either set of carbs. Surely your e.t.would be better with the bigger ones, assuming they are jetted correctly. Quote Link to comment Share on other sites More sharing options...
camatv Posted January 30, 2010 Author Report Share Posted January 30, 2010 yea wow. if you just change carbs and you already are reaching the nominal rpm limit of the bike the TOP SPEED will most likely be the same. you need to judge the bike by ACCELERATION i HATE it when people ask me how FAST my bike goes anymore i tell them it does 190 mph.. 35mm AIR STRYKERS will give a much better response to lower throttle signals than the 34mm pj's.. i would chose them over the 34 pj's on any trail bike.. cubs with stock carbs are a LOT of fun. people will see that you have stockers on it and think oh i heard that a cub wont run with stock carbs then you can spank them ( if your shizzle's tuned right..) and see the disbelief kinda like if/ when you whop cubs with stock cylinder 350's.. NOW if your carb's are a lil rich and you go STABBING them full throttle. no throttle. you will probably see issue's with the response of the motor. if your trail bike seems BOGGY with larger carbs PLEASE experiment with needle positions and slow jets. i bet its a lil to rich.. you miht just suprise yourself.. rember if you can cause your bike to go into a lean rev with the air screw's your really close to correct on the slow jets.. to me i just see to much emphasis on MAIN JETS and ohh my bike has a bog/hang/studder/poopie section in it and nobody can figure it out or they just live with it. dont be afraid to play with your carbs slow jet/ needle position, idle air screw.. plus you get that set right and the main jet will be much easier to get right.. Quote Link to comment Share on other sites More sharing options...
RagunCajun Posted January 30, 2010 Report Share Posted January 30, 2010 I Asked who did my port work. Then I went from there with my carb selection. Wouldn't a general rule be when in doubt ask your engine porter? Quote Link to comment Share on other sites More sharing options...
camatv Posted January 30, 2010 Author Report Share Posted January 30, 2010 yes and no there is even debate between engine builders as to what carb to use. sometimes its a matter of guessing!! you say i want an MX port/ head/ carb set up now if you asked me i'd say then dont waste your time on a banshee for mx racing.. (i can set one up BUT overall you'd be wayy better off with some other type of bike) now most peopel would get pissed if you say that to them but i am known for being brutally honest even if it means loosing a certain "job" there's things i just wont do.. on the other hand what carbs would work well for : MX riding: need strong acceleration and very very broad power and very low to no pipe "hit"..? trail riding: i'd say fire roads? tight trails? long windy trails rocky technical trails? dune riding: again.. put put trails, goofing trails? tree shooters, hill climbers? play dragger? drag racing: asphault? rider, jockey, frame weight, fuel used, sand, dirt, asphault, hill racing? would all these conditions need a different motor type? wouldnt all these conditions almost describe about 90% of the average riding you might do with your banshee over a years period or so? Quote Link to comment Share on other sites More sharing options...
R.Hunt1 Posted February 24, 2010 Report Share Posted February 24, 2010 first off this is a great thread anyway i am starting a project and i have decided that i an going to use a banshee engine for my power plant i have owend many quads and i just fell in love with the power i had with my 01 banshee i did not build it but it ran beautifully just to sum it up (fmf gnarly&power core, vforce2, k&n) not a whole lot in the engine i put a lot in the suspension but that does not matter with this build anyway i loved it the bike ran so good i mean seated 1 kick starts every time no matter the temp (95deg or 10deg) and would just idle all day if i wanted i never lost a race with it granted i knew when i saw a realy built bike thta was out of my league so why bother sorry to ramble on i need low end for gncc type riding i know the gnarly pipes are good but not sure what elae like i hear 2n1 carb setup? things like that ya know gearing, tires, porting, CARBS, pipes, reeds, just any usfull info sorry if this is the wrong thread for this post i have just been reading through the post and people have had somje good input Thank!!!!!!!!!!!!!!!!!!!!!!!!!! Quote Link to comment Share on other sites More sharing options...
qboronyrican Posted February 26, 2010 Report Share Posted February 26, 2010 When I first built my 4 mil cub motor, all I had were stock carbs and T5 pipes. I wanted to run the motor, but I didn't have bigger carbs and better pipes or the money to buy them... It ran like crap. Absolute crap. Quite a few people told me it was because of such small carbs and trail/dune exhaust. It ended up being a bad air leak at the base gasket, a bad flywheel AND the deck surface of a brand new cylinder had a little dip causing water to seep in. Once I got that fixed, it flat out ripped with stock carbs and T5 pipes. Even made 84 HP and change on a dyno. (Within a month I had 35's on gas and inframe RDZ/Shearer, but that's not the point) My point is...will smaller carbs and more restrictive pipes work on a larger engine? Yes. Safe to say anyone could tell you you're not going to get the most HP out of that setup...but they will absolutely work, hands down. how did you find out the flywheel was bad?...my shee doesnt seem to run as good as ive heard it should....maybe i should look into these problem Quote Link to comment Share on other sites More sharing options...
boneyardbanshee. Posted February 26, 2010 Report Share Posted February 26, 2010 This is what I know, if you run Paul Turner Mids stay with stock carbs. I tried them with 30mm OKO's and never got them to work together. Just too much carb for the rpm range. Stock carbs back on and they work great now. Quote Link to comment Share on other sites More sharing options...
gusto Posted November 29, 2017 Report Share Posted November 29, 2017 Bump! on a 421 serval ported, how much hp will be held back running 28pwk compared to 35pwk? riding is mostly open road Quote Link to comment Share on other sites More sharing options...
ginger Posted November 29, 2017 Report Share Posted November 29, 2017 1 minute ago, gusto said: Bump! on a 421 serval ported, how much hp will be held back running 28pwk compared to 35pwk? riding is mostly open road in my mind it depends on what type of riding you are doing and where you want the power. Quote Link to comment Share on other sites More sharing options...
gusto Posted November 29, 2017 Report Share Posted November 29, 2017 What I want to know is what is the difference in hp total, and is there a difference on bottom end? I’m sure I would see a top end increase but maybe not.... like I said riding is open road, no tight trails Quote Link to comment Share on other sites More sharing options...
ginger Posted November 29, 2017 Report Share Posted November 29, 2017 it will gain you some on the top end, but hurt your bottom end pretty good. i would say 33's before 35. unless you are duning Quote Link to comment Share on other sites More sharing options...
gusto Posted November 29, 2017 Report Share Posted November 29, 2017 I would like to see a dyno and see if there is an actual change on the bottom. I have read conflicting reports Quote Link to comment Share on other sites More sharing options...
Ayesully810 Posted December 3, 2017 Report Share Posted December 3, 2017 Bump! on a 421 serval ported, how much hp will be held back running 28pwk compared to 35pwk? riding is mostly open roadI lost 10 hp going from race fuel and 35s to pump gas and stock carbs. My guess is 6 of it was from the carbs. U will have more bottom end for sure. Sent from my LGMS210 using Tapatalk Quote Link to comment Share on other sites More sharing options...
gusto Posted December 3, 2017 Report Share Posted December 3, 2017 Damn that’s alot Quote Link to comment Share on other sites More sharing options...
Ayesully810 Posted December 3, 2017 Report Share Posted December 3, 2017 Damn that’s alotHonestly it didnt feel like it though. Top end didnt feel different it was more of the punch on the bottom end from the drop 180 psi to 150. Dont be afraid to run smaller carbs.Sent from my LGMS210 using Tapatalk Quote Link to comment Share on other sites More sharing options...
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