4stroker

thanx for the input jim that is a little high isnt it! the highest i got it to rev with Toomey T5s on it was 10,200 rpm. that was with 185psi compression. (16/42 gearing) like i said i want to buy shearers but im worried about having less bottom and mid than i do now... i like the idea of the PT high revs having more hit down low and mid than the toomeys but im worried about them not working real well at high revs when my exhaust duration is going to be 210 degrees! Jim do you think the PT high revs will be better suited than the toomeys im currently running? thanx, mark. P.S i have machined the housing of the PV pully a little and made a custom plate that is alot thinner than the standard yamaha one and the toomeys fit fine so everything else should too..

clearing the PVs are not a problem i have a found a way to get all types of pipes to fit not sure why everyone doesnt do it!

what exactly have you had to do to get it dialled in... pm if you like! this thing we are running the top end doesnt last more than a few hours (if that) we are running way rich jetting (39mm keihins, eek needles on the 2nd highest clip, 180 main jets) and it still nipped up the right side doing a plug chop on a fresh top end it is running 3.5 thou bore clearance, and an 8mm squish with 32thou clearance. we are thinking of increasing bore clearance to 4.5 thou and squish clearance to 45 thou... what do you run the port openings is just something we noticed while having it apart and thought it may contribute to finicky jetting requirements what does your t rex motors rev to. this one revved to 10200 when it died... also do you cut the window on the pistons to match the intake ports. coz on this particular motor the piston skirt covers up half of the outside intake ports.. if you know what i mean..

hey man havent had a chance to play around with it yet coz ive got the motor torn down after i thought i had nipped it up i whipped the engine out of the frame and got the head off and turns out everything is a ok (still gonna have the machine shop guy take a look at the bore) anyways im putting the standard top end back on it for now to go flat track racing, as i want a fairly standard and reliable bike for starting out on. in the mean time im gonna decide on what pipes to get for the RZ top end, and also build a complete new wiring harness from scratch with all the zeeltronic components. i figure by the time i get it all runnin ill be ready for more power at the track! i was thinking of ordering a set of shearer small bore pipes but im not sure if ill like em, im thinkin Paul turner high revs would be a better all round pipe, but im guessin there not really designed for these high exhaust durations either... or are they...

i just threw a degree wheel on my rz motor and measured some port timings it seems that the exhaust duration is 210 degrees, the front transfers (exhaust end) are 130 degrees, and the rear transfers (intake end) are 120 degrees what pipes should i get i want a pipe to take advantage of this big port timing but i also want as broad a powerband as possible (hence why i am using the ypvs cylinders) keep in mind i have the zeeltronic programmable PV controller and can tell my PVs to open and close whenever and however i want! thanks, mark

this engine is used for flat track and oval track speedway, short and long circuit have no interest whatsoever in a non pv cub also want to learn something and sort this thing out rather than giving up and going with something else... thanx everyone else for your input will give k&t a ring today and see if they can help

yeah its a 7mm stroke, 72mm bore Trex. was purchased from DASA about 3 years ago and assembled here in australia. it seems that the transfers and even the exhaust port are partially covered by the piston at BDC. its almost like the cylinder is meant for a 10mm crank, however at TDC the piston is flush with the deck.... who is a reputable source we can talk to about this particular style of motor (TREX)? we rang DASA but they werent much help, they were very vague and pretty much said "yeah thats how it should be" we are having reliabilty issues with this engine and things like this arent instilling much confidence in us to gt it sorted! can anyone point us in the direction of a "t rex guru"? any help much appreciated! thanks, mark

you could try that however when i tried it i cracked the basket due to the nature of how you have to attach it this is what i did (prolly wrong but anyway..) 1.ground down the end of the four pins (rivets) holding the basket on the gear 2. knocked em out of there with a punch 3. made up four new rivets on the lathe 4. slotted them all in and tried to "rivet" them on by punching the end of them to get them to mushroom out over the plate on the back of the gear i was very careful and used a small drift on the other side of the rivet but even still i cracked the basket im not sure how a billet basket attachs (mines on order) but im sure this procedure would work because it would be much harder to crack the billet basket, compared to the stock cast one file the grooved basket you have and run that until you haved saved enough pennys for a billet!

on a trex motor, should the transfers and intakes be completely uncovered at BDC

i would like to here from experienced builders/porters on what they would do to a t rex motor to make it last in extended WOT applications, like Oval track speedway or desert racing. it seems this motor runs extremely hot and can not handle max rpm for very long. the specs on the particular motor im talking about are: 7mil stroker, 72mm bore trex. it has rossier engineering stamped all over it so im guessing it was ported by them v force 2 reeds, 39mm keihin carbs. 178 main jets, eek needles on 2nd clip from the top. 185psi compression. how much bore clearance should we run on this motor also the window on the bottom of the pistons covers half of the outside two intake ports, should we open the skirt up to unblock this also what sort of ignition curve should we run any help greatly appreciated

the movement is normal the clutches are put together with cushions on either side of those four pins that hold it together. i have taken a few apart now, and there is room in there for movement (radially) i would file the fingers down on the grooved basket for now and run that. if you dont like the way clutch works, then buy a new basket, but try it first, i have filed baskets before and been happy with the clutch action. one tip though is dont mix and match the drive gears for extended periods of time. if you have the crank gear to suit the spare basket you have swap it with the one on your crank.

i sure did im going to have to talk to my engine porter about the powervalve curve, maybe he will have an idea on the best ignition curve to run as well with the PV controller i can grind the exhaust ports higher and tell the valves to open higher, while still closing in standard position for lower revs, or even lower than stock if i want its gonna be fun!

my buddy just nipped up the right side on his trex what are these pistons out of? (72mm) are they a sea doo part or something? thanks, mark.

i have just ordered the programmable cdi and programmable power valve controller for my rz shee from zeeltronic www.zeeltronic.com does anyone know how i might go about finding a suitable ignition curve to use as a base map to start with? anyone created any of their own curves, wether it be for vortex, dyna tek etc etc... thanks, mark.

ive never heard of torch works before, you say they are good snopczynski? has anyone else used them? do they hold more water than a stock radiator? thanks, mark

any sort of grease? high temp bearing grease or something would be the go yeah?

should i coat the crank seals with anything before installation? also should i run a bead of 3 bond around the outside of them to seal against the cases or just leave it? thanks, mark

can anyone tell me the dimensions of the clutch push rod in a banshee please?? i need to make one. thanks, mark

i have been emailing borut (zeeltronic) quite a bit lately as im buying the PV controller off him he is a really switched on guy and is great for replying to emails and what not. his prices are real reasonable too. UPDATE i fried my clutch again, i didnt have enough slack in the system. i am a dumb fuck. splitting the cases again tonight to fix it... also broke the clutch basket gettin it off... soooooooo i have ordered a hinson basket and tryin to find a pancake here in australia, need to get my act together though, my race is in 6 days....

so this is something i can do myself then? it doesnt need to be balanced or anything?

when you buy a hinson or any other brand basket, does it come with new fasteners to attach it to the gear? how do you get the original basket off, and how does the new one attach?

i would like to hear from people who have FZR1000 fibres in their clutch i recently installed a new clutch with stock banshee steels and FZR1000 fibres, and 6 heavy duty springs sinced then i have fried 2 sets of actuator/rod/ball/adjuster assemblies. the second time i had just put it together and rode it for about 1 minute (no joke) about to split my cases again to fix it. i adjusted the clutch exactly as the book says to. are these fibres too thick and causing these problems? or do i just need more freeplay in the system than the book says? please help!!

yeah man hurry up! what does it need to run?>

i am not sure what the go is with the PV motor. i need to spend some time and test it, hopefully its just the control box, if so i am going to buy a zeeltronic programmable controller. if its the motor, i will have to scour the wreckers for an R1 exup motor. at the moment i have removed the motor and controller and locked the PVs in the open position. its alot of fun but a little uncontrollable. it will be fine though for the race i am doing next weekend. after that i will sort the pvs out properly did you know that if you use zeeltronics cdi and pv controller, you can use the standard banshee stator and flywheel? pretty cool huh! maybe i will build that 4mm Rz after all....

when the clutch is engaged (ie driving) do you want the adjuster done up so that there is no slack between the actuator, rod, ball and adjuster? because when it is driving, arent these all spinning? and if there all touching, wont they weld? i know that the only decent way to fix this is to buy a pancake bearing, but im trying to get this running for a race next weekend and a pancake wont get to me in time. thanks, mark