YFZ350kid

Did you get all of the chunks of waterpump gear out? Sounds like you have some plastic on the gears jamming it.

I've posted a couple times over the past 3 years that i was getting the banshee back together, well. Finally got the motor done, now just gotta get it back in frame and do some cleaning up and shee'll be done. I'll post pics this weekend when shee's running

No so much looking to save a bunch on jets, just wondered if it works because I have access to a lot of Holley jets for free... It's no biggie to buy the one I need. Just looking to find out some info.

a friend of mine who used to do jr. Dragster and is now a pro level drag racer told me about using a jet extension and holley jets as a cheep alternative to using mikuni 4/042 type jets. has anyone done this successfully? also what size range should i look for to equal around a 230-350 mikuni size? Thanks

I'm going to be doing a complete tear down and rebuild on my '97 Banshee. I'd like to replace the stock suspention with updated and better parts than stock but I'm not sure how price is going to work out for me at this time. my basic question is, on the frame, where are you all getting replacement bolts and hardware for all of the suspention and all associated parts? also, for those who have done a full frame refresh/rebuild, what extra parts did you change out/rebuild? Thanks for any info. for what its worth, Im in the Las Vegas, NV area.

I will be taking the cylinders into work tomorrow to clean them and measure them, but 85-90% of the crosshatch is still in em, so i shouldnt have too much of a problem... I'll update as i take the motor farther down, gonna have to split the cases on this build, now i just gotta remember to seal the damn things up correctly, and I'll deffinately do a leak down before final install this time. lessons learned!

and so begins the process... did a leak down test... left crank seal had a pinhole leak... and a couple very very small leaks around the case, guessing it was the case sealant i used... live and learn, just wish i learned more the first time... anyhow... heres a couple pictures, left cylinder has the hole in it. right spark plug (little rich but atleast safe) Left spark plug (bright white, little metal, not a good sign...) pulled off the coolhead, amazingly the domes are fine pistons out of the jugs

i dont think compression matters much... if i remember correctly the right cylinder had metal on the spark plug, i'm hoping the cylinders didnt get jacked up as i sent them to a machine shop for the last rebuild... i know my jetting is a bit off, but on the rich side of the spectrum... i had 310 mains and 30 pilots, plugs were dark when ever i checked them.

good call... ill build up somthing before i start the tear-down... i'm really hoping for somthing silly to be leaking like intake boots... i'd hate to split the cases again to replace a basically brand new seal... oh well, live and learn. i'll do my best to post pics and ask questions as my build progresses.

well, ive decided that as much as I'd like to spend the money sending out my motor to a pro for a rebuild, i think ill give it another go in house... im just tired of the 'ole girl sitting hurt in the garage. I havent torn down the motor yet as it blew about 2.5 years ago, i think it went lean again after a fresh build, only had 5-10 hours on the motor... anyway, are there any checks that I can do before tear down that i should try? hopefully it will just be a easy top end rebuild, but again any advice would be welcomed...

thanks for the info guys... I'll probabily start calling around to the guys at FAST, wildcard, HJR and others. thanks for the info everyone.

Hey everyone, I'm a Henderson, Nevada local and am looking for a reputable builder hopefully locally for my 1997 banshee... I've done top-ends before with varying success... but I currently dont have the time/space available to do a re-build/re-seal on my shee. shee's been sitting in storage for 3 years now with a blown piston and i'm getting the itch to have her runnin by this coming fall. is ATV Cycle Sports (steve abbot) still the recomended place in vegas or is there somewhere better? I've had mixed feelings on Atv cycle sports for quite a while. Just looking for some suggestions... im sure FAST is still king of the shee world. help a bro out to get my girl runnin. SHEE needs some LuVin

hmmm, that would make sense, but i dont think its the tank vent... oh well, my new (ya i went to the dark side) raptor 700 should keep my dune season alive... and ill get the shee back up when i get the time and money... still gonna pull the head today though, just to see whats up, im hoping for somthing stupid like a pinched o-ring, but im expecting the worst thanks for all the info and things to check for

well, to answer the race gas with 21cc domes is cheep insurance, atleast i thought, to help prevent detonation and possibly help the motor run a bit cooler... again, the 310 main for the carbs was jetted fat to try to keep it together... to those of you that are in the know, could over fueling cause a similar situation to going lean in a 2 stroke? i know in 4 strokes that it would only cause a rich miss if anything generally... thanks for all the ideas... im glad this forum had constructive things to day, i posted my issues on dumontduneriders.com and got ripped up by a couple folks on there...

0.046 and 0.044 are my squish results right after it was built i did a cylinder leakage test at 10 psi and the leakage gauge read 4-5% leakage, the last time the motor blew when i put a hole in a piston was due to a cracked intake boot, it leaned out the right side while running comp and boom, thats all shee wrote... my water pump was just changed to a pro design billet impeller and i had the guy in the radiator shop where i work go through and clean the tubes and straighten the fins for me, so im not thinking cooling system... would the crank seal take that long to show its not seated correctly, i mean it took 15 hours of running for it to go lean and i used propane to check for leaks before putting the covers back on and i got nothing around any seal or gasket... im gonna wait a while before i tear down again, i might pop the head off this weekend but im not too sure... ill keep you all informed as i go back inside the motor again thanks for all the replies and ideas

im sorry, i said my needle position wrong, im second from bottom, not top...

i was thinking that is possible, but not very likely, i checked and doubble checked everything, i havent done a preliminary tear down yet to see how bad the damage is, im just trying to see what all everyone would check in the same situation... the odd thing is that when i push over the kick start with my hand it has equal force on both sides... i gotta get my compression tester from work and i can see what it is on both sides... im honestly looking into getting a 700R for somthing to ride thats reliable as the last 3 times ive had this one out its ended up the same, tow back and take 6 months saving up and ordering parts to repair, researching everything, then finally putting it back together as carefully as possible... the thing is as far as the carb float getting stuck im not thinking its very likely with all new components and absolutely no symptoms sooner... i'd have expected a problem within the first hour of riding not 4 hours into it... or even while doing the heat cycles...

dang banshee has me confused... ok, from the top, got this 1997 banshee last year after my 89 blew up... my 89 was a pile, and i got this 97 as a trade + 1500 cash... anyway, this 97 has fmf sst pipes and power core 2 silencers, 21 cc domes in a pro design cool head, bored .030 over, stock carbs with tors removed, +4 timing. 310 mains, 2nd clip from top of 6 grooves on both needles, carbs were just rebuilt and cleaned very well. and a k&n airfilter in the box with outerwear over the filter element, no lid on airbox, new intake boots and boysen carbon reeds... i live in Las Vegas and the banshee is for use at Dumont Dunes 99% of the time... oh, im running 100 octane fuel with 40:1 fuel/oil ratio, ams oil for my oil well, i rebuilt the motor to include a new hot rods crank, all new seals, new pistons, new domes, o-ring kit for cool head, pro design water pump impeller and multiple other little things for the clutch and transmission... get it all together and started it up, fired up fine, did 10 hours of heat cycleing and re checked torque on every bolt on the motor... no problems... head out to dumont dunes yesterday morning for some test and tune style riding, just gettin in ready for the season, no major long pulls at WOT and only running 30-45 min untill a nice 20-30 min cooldown with the wind cooling down the motor... after about 4 to 5 hours of ride time just running around a small bowl on the back side of the dunes it started bogging really bad, well not having any good tow vehicle i had to get up out of the bowl before i could shut it down... get pulled back to camp, pull the spark plugs and the right side showed a bit rich still and the left had aluminum build up on it... so needless to say, blew a piston... now this is the opposite piston as what went out the last time so something changed from the last problem. any ideas would be wonderful to have, Thanks

thanks for the ideas, after closer inspection of the left carb, the float valve (needle/seat) has a small ring around it preventing a good seal... im waiting on the parts now but if i run it for about a minute with the fuel off once the level drops a bit in the bowl it cleans up and the plugs are the same color... now i just have to somehow keep myself occupied away from the banshee till the last couple parts come in.

I got the banshee back together today and kicked it up, started 2nd kick... no worries there... but after about 20 min of running the left cylinder was still smoking much much more than the right... shut it down, pull the plugs, right cylinder is a dark brown as expected my jetting was a bit rich, but the left was wet and white... carbs were just cleaned and checked over. any ideas guys? 25 pilots, 310 mains, 3rd clip from top, fmf fatties/power core 2's and k&N filter w/ no lid, timing at +5 at first I figured it was a bit of assembly lube from the build, but i think it would have burned off within 20 minutes... thanks

HAHAHAHAHAHAHA gettin a good laugh off of that one! well, my parts guy aint callin me back so I guess ill go ahead and file it down myself... or maybe ill wait till next weekend... i just want to get it going, dumont season kicks off in 2 weeks... and i aint ready yet

hahaha, true that... but I'm just going to the safe side... if there is a flaw in the machining of the piston at the wrist pin, then it makes me wonder if there is a flaw in the rest of the piston...

I know Wiseco pistons are awesome and they are what ive used for years but I was wondering how many people have had faulty pistons out of the box? I'm finally getting back to the banshee project after a month or so of waiting on parts and the weather to cool off, and now I go to install the pistons and one of them has a burr in the hole where the wrist pin goes. so I cant proceed with install until I get this problem solved, i've sent an e-mail to wiseco already and am awaiting a response. anyone have a similar problem with their pistons before?

if your backfiring on decel and when you let off the throttle to shift then check the pilot jet, good chance you need to go up a size or 2. for the popping down low when its cold, let it warm up first... from my past experience with an 05 yfz that i used to have, the cam mod made the bottom seem lacking and sluggish, but it let the motor breathe better up high in the revs making it feel a bit more like a 2 stroke. my 05 used to backfire on decel once in a while, but it was never an issue. but if it does it constantly as i said before, bump up you pilot jet.

well, as i posted a couple of weeks ago, I had the banshee running... after a total of 7 hours of heat cycles and about and hour of run time checking jetting I went out to Dumont Dunes to have some fun. got there, let the motor warm up, did a fast pass, swapped plugs, did a 1-6 run, checked plug color again, just a tad rich but not horrible, go ride for 2 hours then call it a night. go out in the morning start it up/warm up, go ride about 30 minutes, making an easy pass up comp hill and the right piston explodes in the cylinder... hit the kill switch and coast down the hill, get towed back to camp and pull the plugs, right side is melted and metal all over it, left side is perfect white... moral of the story is, when you do a rebuild, make sure to buy new intakes if they may be questionable, the left side had a crack in it that I didnt see when I was re-assembling it and didnt show itself untill running around the dunes for a couple of hours... I havent taken anything apart on it, but the right side has 0 compression, but the left still feels fine, everything will be torn down once I have the money to start rebuilding again... looks like I wont be able to do it for $300 this time. anyway, thanks for reading all this crap, I'm still a little pissed about the whole situation.