ryskie22

anybody got any ideas someone has to have ran into this?

my pistons and domes are perfect been running the silencers for two seasons and the silencers are not clogged the perferated tube is spotless like you burned it out with a propane torch but it is longer and the same size in diameter as the cpis.

ok i have a 421 cub on gas with 39 pwks 160 main and 52 pilots with dek in the middle position, cpis with cascade silencers. the problem is that the motor on the the topend wiill nose over and have a slight miss to it, i have checked all electrical from a known good bike(actually switched everything on it one at a time) now have also tried jetting it down and up with same results so for some weird reson i decided to try me cpi selincers bingo that fixed the problem! i am confused as to why it seems that there is being too much heat being held in the pipe the cascade silencers are bone dry no oil residue at all my cpis are dripping oil. i have taken them apart and found no obstructions just very disscolored packing and burn holes in the front of the packing. when i just cruise around with the cascades on it feels like my head pipes are on fire againts my knees! but with the cpis not so. its geting the spark plug so hot its cracking at the Spark Plug ceramic Insulator and is fine with the cpis. now i know that a lot off people run these type of silencers and i would like too as well if i can figure out what is wrong with them. oh also just let everybody know how my pipes are getting my stinger tubes have full leangth heat sleeves on them and they have burnded through them and into my plastic!

anybody got any ideas?

yes i am replacing the stinger tube also do too the cascade silencers are longer and yes it felt great too have my motor back to normal and being able to race again. just need to figure out why, maybee there is a fix were i can still run the cascade silencers.

well got some intersting news for you guys and gals went to winchester bay oregon and still have this flutter nosing over problem butt i brought my cpi silencers with me this time and put them back on from cascade silencers and bike ran great,pulled like crazy for 3 hours out on a ride, reinstalled the cascade silencers and wamo back to the problem now the question is why? any input would be apreciated. oh yea i have checked them for any issues inside the silencers none were found!

well got a 421 cub on 110 race fuel with a topend flutter not a hard miss that cause's the bike to fall off on power,it use to be a intermitant problem now i can make it happen all the time, i have tried changing stator,flywheel,cdi,plugs,coil,plug caps,jetting up and down 5 sizes as well as the needle position up and down and with a differnt needle completly.have taken wiring harness completly apart and checked it over very carefully,sanded frame to bare metal were ground is and even added more grounds in the front.tried smalller gap on plugs and got the pulsar at 0.15 at the flywheel. any help would be apreciated banshee hq has never let me down these guys on here no there stuff , so thanks in advance! here are my mods 421 cub 68 miill bore v-force 3 reeds pro design intakes 18cc domes (cascade) small bore inframe cpi with cascade siencers dynatech igntion on position 3 39 pwk main jet 160 pilot 52 dek needle in the third clip air mixture at 1.5 turns dual pingal valve br8es plugs at 0.26 gap turbo blue 110 fuel 4milll long rod with tz bearing hotrods straight cut gears hinson basket direct drive 3 heavy 3 light springs toomey radiator with temp gauge

thanks for all the replies, sounds like i need to make some runs and check my egts real close and go from there. i might re dyno with the 39s at the end of the year, i will no then were my jetting will wnd up. just was going to ride it one last time before winter realy gets here to see if there will be any other issues before the dyno, gotta get the kinks worked out!

funny you say that 35s and 39s dont differ much on jetting on the same motor, i had 35s before with the same jets and it seemed you had to rev it hard before you launched or it would bog, only when the sand was heavier and it would not like to roll on the throttle very well it would sputter out the pipes and the more throttle you gave it the worse it got,now you could always clutch it and it would be gone. never tried to figure out if it was lean or rich? only ran them a season and put 39s on her,so i may still have that same problem? my 35s i think were good on main jet,i warmed her up at the beach on a 80 degree day and put two new plugs in her and made a pass up to 5th gear and shut her down,pulled the plugs cut them and had just a hair over a 2 millimeter brown ring. thanks for the info

do you think 160 main might be to lean?

need some help here guys got a 421 cub on gas with 39 keihin pwks, trying to get a starting point for jetting.I ride at sealeval to 500 feet at the coast,got a 160 main and a 52 pilot now what do you think! I did search a little before i posted and it seems everybody has 35s.

yea no grooves it is a pro design, have tried that too!

well its a 421 cub and i have water or condensation in the trany oil after one weekend and have replaced the water pump seal and bearing and the o-ring on the pipe and still no change, dam thing still does it, what my qestion is that can a high pressure cap on the radiator cause to much pressure and push it buy the water pump seal? i have a 22 psi cap. i havent tried swithcing it to a stock pressue cap yet but that is next i guess.

thanks guys broke them down today and sanded the wheels and bead sealed them, dont think they are going to spin now!

i will break them down this weekend and see what i find and clean the beads and rims and seat them with brake clean,as awr stated. thanks for the info. has anyone tried bead sealer? the black goo in the metal can?

my mods are 421 cub on gas with a 6 inch swinger and 10 paddle superlight extremes. the problem is that i am spinning the wheels in the tires and it will dart left or right very agressive to the point i half to let off,(it doesnt do it everytime it is launched), i run the tires around 3 to 6 psi depending on how heavy the sand is, i know that it is a very agressive setup for launching. just wondering with this setup if i need to run the tires that low? i didnt air them up yet to see if they still spun. i went from 60 horse to 95 and road it this last weekend for the first time and discoverd this problem,sure love the power though,cub motors for the dunes is very fun.

the temp today was only 55 degrees f but mostly just ride at the beach in the summer were it is like 70+

i rode the bike today and im thinking it is lean but want some other opions on this, what i have is 421 cheetta cub on gas kicking compression is 190 and cpi pipes, boysen reeds,2-35mm pwks with a 52 pilot and 160 main and stock needle what ever they come with and it is in the middle clip. the elevation is sea leval to 500 feet. what do you guys think?

thanks guys for the replies, i bought some cpi s tonight and will try the t4 s and the cpi s on the dyno to see what the difference is, it will be interesting. plan on dynoing this thing in the next 2 to 3 weeks, i will post what happens.

am just wondering if anyone has ever tried t4 pipes or no any thing about them, they look just like a cpi but smaller, i have tried them on the dyno with my old setup and then tried cpi s and there was no peak horsepower difference, just reved to 10000 instead of falling of at 9000 wich is what the t4 s did. my old setup was a 350 bored .060 with 19 domes in a coolhead and boysen reeds and 33 pwks,at 6 degrees timing, and it ripped but always didnt seem like it would rev out, you had to shift it quikly. so now i have a 421 cub with boysen reeds and 35 pwks and 18cc big bore domes in the cool head with t4s. havent rode it just trying to figure out if cpi s on this setup would make more peak hosepower or just rev out more than the t4 s, nobody seems to no about the t4 s,any input would be appreciated

just to let you guys no my compression is 188 psi at 654 feet above sea level, is that to high for you guys on 110 octane?

QUOTE (C&B @ Mar 16 2009, 06:10 PM) <{POST_SNAPBACK}> Holy shit man! way too much comp for what ya got goin. Put some 21s in that thing i just want to know about the pipes if cpi s will make more peak hp than the t4 s or just rev higher, compression isnt my queston guys, thanks for the concern though.

my compression is 200 to 205 and its on gas,they are just 4 mill cheetta cub cylinders with no port or clean up on the ports

am just wondering if anyone has ever tried t4 pipes or no any thing about them, they look just like a cpi but smaller, i have tried them on the dyno with my old setup and then tried cpi s and there was no peak horsepower difference, just reved to 10000 instead of falling of at 9000 wich is what the t4 s did. my old setup was a 350 bored .060 with 19 domes in a coolhead and boysen reeds and 33 pwks,at 6 degrees timing, and it ripped but always didnt seem like it would rev out, you had to shift it quikly. so now i have a 421 cub with boysen reeds and 35 pwks and 18cc big bore domes in the cool head with t4s. havent rode it just trying to figure out if cpi s on this setup would make more peak hosepower or just rev out more than the t4 s, nobody seems to no about the t4 s,any input would be appreciated

yes you are very right i was going insane myself until i calmed down with my freind wiskey and stared at the the two case halfs and then it hit me the dam keyway. hey my fix was a .o15 thick big block chevy valve spring shim with some yamabond on the gear side placed inbetween the crank gear and the water pump drive gear to cover up the keyway, also put some yamabond on the keyway, it seem to work really good with that shim inbetween like that.