Sym Jet Basix / Eurox Problems

Forget headlights and all that other stuff.

PEDRO IS NOT FIXED !!!

riding down a major city road 40mph limit so i was riding at 40mph when all of a sudden, NOTHING, no lights no engine nothing it died on me like right there and then. scramble to get into a safe lane and pull over then mount the kerbside pathway. stop switch off ignition switch back on give pedro a kick and puff puff puff , the kickstart was very loose like there was no piston in the cylinder type feeling. so i start walking and pushing this POXY scooter along, 15 mins i waited before someone stopped traffic to let me cross the road pushing this darn scooter.

so its been like 40 mins huffing and puffing and i walked about 1/2 a mile at most ( i just cant do this any more not good for my heart) and i am so angry with myself forking out the £144 quid to get it fixed and its just Not been fixed, yeah it runs but i mean just bombing out whenever it likes is just not on anymore. so there i am real angry ( kinda swearing at it and smoking from my ears n nose like a dragon) i yurn it on and give it one amighty kick , LIFE OMFG ITS ALIVE, yeah alive but with a variator rattle , i just made it home, broke a few rules riding along a cycle pathway to cut out all the major roads ( i mean bikes just not safe to ride i think when its like that) with a top speed of 15mph again, yeah i went super slow so i did not overheat it or throw the piston or anything out.

Had enough of Samyang bikes for now and means no halloween ride out either, i cant trust pedro to even make it let alone just cut out when it likes. worse thing is i do not have the money to buy a new scooter either, i have thrown so much into pedro and its bloody problems i am left in the black.

so what makes a bike just drop out , ie no lights or anything, going from running smooth as anything to totaly dead in a matter of nanoseconds ? Blown out top end - mild heat sieze - crank compression loss - magneto ( im running an ac feed mag and cdi ) ?

 

Going to run pedro out staturday night to the meeting, with the intention of it hopefully cutting out that way i can get it onto the back of a lorry and home. once its home i can decamp the front fairings and the rear/side fairings to get to the major wire loom junctions and connection.

from their it will be a pull each connector apart check its seating repinch the spade connectors and treat with swarfega duck oil. sand and remount both frame and engine grounds to make sure there is a perfect joint and again treat with duck oil . i think its a 100% poor connection on the stator side to the cdi/regulator-rectifier so i will be starting there first.

one major pain is the cdi is housed in the tail of the bike and the reg-rect up under the front fairing. i am maybe looking to move the cdi upfront with the rest of the electricals keeping it in a more easy area to get to. ( seat bucket - front tank fairing left-right-rear panels - battery and cover needs removing just to get to the starter relay and cdi ) so yeah having that starter relay and cdi up under the front fairing will make electrical problems more easy to get to and replace.

Once the problem has been found and put right PEDRO IS BEING SOLD and i am moving to fourstrokers ( trying to get enough pennys up to buy a honda grom - honda cub 90 - honda innovis/wave)

 

SO 2nd september bike went in for a full rear clutch, thats a new rear pully and clutch - springs and contra spring. naraku belt and naraku rollers. speedo reading was 12150 km.
Today speedo reading is 13148km., thats 600 miles on this new clutch / rollers and belt and its a derestricted 50cc , not no high end tuner job.

now i am riding along when all of a sudden bike just starts to bog down, i pull over wait a few seconds and it runs off perfect. 1/3rd a mile later it does the same thing, i pull over wait few seconds , rev her up and all is good.
i now go out on a long ride, its been raining here so i though its just a bit of damp and the 3 days sitting not being run.
Pull up to first set of lights and bike is acting funny, even on idle the bike is pullying forwards, you can feel the motor and clutch engaged. ride goes ok so i return home the long way through the windy countryroads.

Go to PULL UP outside my home and the bike just stops dead, like someone took the key out, i am like WTF jump off and go to roll the bike to its ground security fixing but it will not move, i try rolling it forwards and its very hard. IT FEELS LIKE A CLUTCHED BIKE STILL IN GEAR , you know that as you push it you hear the motor turning over and feel the compression cycles as you strain to push it while in gear still. vairator casing is lovely and cool not overheating, cylinder is coolish as one would expect with an AC motor

SO guys heres the question Why is my bike doing this, clutch springs gone ? Contra spring gone ? whole clutch rear pully shot through ?
keep in mind this is not even 2 months old and brand new off the shelf unit thats cost me £80 to buy and another £50 to have it fitted, ( yes in know i could have got a full stage 6 107mm clutch and bell for the same price i was a stupid idiot not to ).

Anyone had this happen or heard of this happening and what was the outcome - full clutch replacement - clutch springs replaced ?

 

Bike came back from the mech with a free no labour check.

the rear clutch and pulley assembly we got came direct from stockist, and when fitted they did not check the clutch nut was torqued tight.
so over those miles its been running the nut had slacked off so much it was not secured and the pully spring jammed it into the clutch bell locking the bell to the clutch and hence why it stopped and stalled out like it has shot a spring or main shoe failure.

they appologized said there was no cost and also made sure it would not happen again, its been torqued down and threadlocked into place

 

What about the fine threads that are on the clutch shaft? Have they been damaged at all?
I would think more than likely they are due to the forces that are at play in normal use.

 

threads were fine , think the stock spring kinda saved them a bit, but thats gonna get changed out same as the clutch springs. going blue clutch springs and a 1.5k contra spring or a 2.k contra spring to go with the new Trek pipe.

just need to choose between a polini overdrive or a malossi multivar .
also got told the sym jet runs the same pully as a speedfight, the speedy carrys a 129mm rear pully so i was thinking if i have space i the rear covers maybe a pug pully would become a poor mans rear overdrive setup ( think my stock is 114mm ) so i would have a higher low range and maybe a little extra top end with a slightly longer belt .

just gotta try to control this rpm peak hp band and try get ontop of this over revving ( not good for my stock crank ) .

 

So now Pedro the sym jet Basix 2006 model is some what running sweet , well when the exhaust has not blown itself a huge great sink hole in it , there are some other areas that need to be covered.

first off here are some pictures of the new Tecnigas Trek in chrome from Adrenaline pedstop ( props for a fast delivery service ), as usual our Sport pipes are restricted, usually in one or two places, a cone in the manifold end and/or a cone in the rear tail pipe of the silencer/ muffler.
i already had the dremmel tool out ready with a carbide cutting/grinding bit fitted. and was shocked to find the Trek came WITHOUT RESTRICTIONS , now thats unusual for an EU legal exhaust system, so it wonders if the pipes been detuned via new methods, ie backpressure - acoustic wave forms. anyways here they are as attachments . and yes its shiney ( not for long lol).

well next up is the variator tuning, i need to get the scooter to around 8000-9000 rpm where the engine produces its max HP , in stock form the sym jet has 3.4kw thats around 4.5 hp mechanical horse power and produces this at around 7000 rpm. thats before you tinker with it and derestriction. once derestricted your HP shoots up depending on the exhaust you fit and the other tinkering done, i would be happy with around 5hp a half a horsepower, but i need to get the variator tuned to hold around 8000-9000 rpm so its always in that sweet spot where its producing its max power output.

on the cards next is a variator upgrade, removing the stock variator for a more newer branded one, this will have more aggressive ramps and ramp angles allowing the new variator to hold the engines rpm better, and coupled with that some new roller weights , going to be swapping out to either three 5g rollers and 3 6 gram roller or three 5g rollers and three 5.5g rollers this should mean the engine revs a lot higher at pulling away so much that its in the peak area the engine produces its maximum hp.

so now i have to decide what i fit up the front will it be a polini or a malossi variator, or could i mix the two and have a Polossi lol

 

Sourcing some extra things

Naraku 17.5 carb ( fits the sym jet manifold thats got a funny like inlet manifold coupling ) what your opinions , as i am looking to grab a 70cc kit when i find one.

Polini HS variator ? again whats ones ideas on these, they do not come with a uprated contrast spring, is it worth going for this and a seperate contrast spring, or should i grab a malossi multivar ?

 

ARGHHHHH !!!!! (Explicit words ) Pedro !!!!

went out for a ride, all was good then it started to happen. rolled of the throttle at a traffic light junction, ( its prime time stacks of traffic behind me) , lights change and i roll onto the throttle , burrr.rrrrrr burrrr .rrrrrrr huff huff bu.rrr .rrr .......... it stops and im left holding up a long tailback.

i drag bike off road and push it about quart a mile to the local morrisons supermart/garage and give the scoot half an hour to cool off ( do not be stupid and grab the exhaust manifold think its gonna be cool'ish, lesson learn major burnt(skind gone very shiney like gloss paint).
Start scoot up and give it a few twangs on the throttle , it revs up like it should, so i kit back up gloves hat button up roll off the center stand and roll onto throttle. burrrrr . rrrrr .rrrr huf huf burr. rrrrrrr ....... it dies again . i start a 6 mile push home ( its gonna take a long time or the old ticker will give up but i need to get scoot home to many thefts of bikes in area to leave it roadside).

Now that sounds like a fueling problem or a lean mix problem, cant be lean as im running super heavy on oil and have just had the carb rebuild and set back up again (£144 quid labour work), but its annoying me so much so i stop about 1000yrds down the road shove bike on center stand and drag out the very crude tool kit , its gotta flat ended screwdriver so maybe just maybe it fits the carb.

i run finger over the mixture needle port and its not even flush, its kinda wound in with around three thread lines showing. so i wind it out a full quarter turn, kick bike over and pin throttle a good few times , in hope it runs out lean and starts to stall out ... but nothing happens bike over revs and i shut scoot down. so for a good measure i add another 1/8th turn out to the mixture screw and pack away, kit up and try to make my way home.
You guessed it im home but i am very wary of riding scoot in this condition. I do not want to spend another 140 quid on three hour carb setup labour charges , but i cannot just drop in any old carb. there are no aftermarket third party inlet manifolds for the sym jet basix.
heres an attachment of what i have to work with manifold wise. and heres a naraku 17.5mm carb that fits that manifold , but keep in mind thats a 12-14mm restricted manifold and the carb is 17.5mm.

if i am semi seizing a larger carb would deliver a more fuel charge cooling effect that the little pokey 12-14mm carb , but the larger carb is running a 90main and 35pilot . onto a manifold that is 14mm ID. that manifold as it sits is how its installed on bike the manifold carb join keeps the carb sitting beside the wheel hugger/mudguard and inline with the stock airbox. any changes me drastic re-conifguring of the airbox using flexi tube , and puts the carb in the way of possible water spray from the rear wheel / dirt flap / drip guard

So question is What Do I Do ? fit the carb and hope it works or try and find something i can re-pattern the mounting holes to fit the basix crank case manifold port and go with a decent known branded carb. ?

 

Here's an idea.
Grab a piece of 6mm aluminium plate.
Mark and drill the four bolt holes and larger centre hole.
Use any rubber mounted carb manifold with 2 bolt fitting and fit that to the new ali plate, making sure the 2 bolts do not protrude through the plate thereby making it not fit flush with the block.
Select any rubber mounted carb you like, fit a twin sponge, open, road type air filter ( found at AD REN A Lin), re-jet to suit.

 

looking at fitting say a seedfight 100cc manifold (they look the same pattern holes as syms) and should be ok for around 20mm id.
then im thinking either that naraku carb or something around the same price but bigger . its shorter than that sym jet one so should give better throttle response to

Airbox i was going to vent mod it , add some extra holes and vinyl wrap the outer cover, so short testing i can cut out and fold in the vinyl making more flow where needed saves running an open filter and the worry of water ingress ( sym jet gets a lotta water spray from the rear wheel even with a mud skirt and a rear hugger fitted ). also while at it enlarge the rubber hose hole from airbox to the carb and fit a larger ID hose so theres a good flow and drag out the restriction hose inside the box itself ( i think i would be better off with a larger carb and bigger jetting 17.5mm comes with a 90 main 35 pilot )

the scoot was fine for like 4-5 mile and i rode fairly hard some of the way, but that total drop out on power really seems like its just to lean. i gave the mixture screw a good 1/4 to half turn out , but did NOT have it re-set when they stuck the new trek pipe on ( so its 100% to do with the new pipe install , so yeah maybe its now running even more leaner, pipe is meant to be a bit better on hp than the tt )

if the speedy manifold dont work i will try grab some 6mm plate scrap, oh and i lost top end speed max now is 40mph from 47 with the vince fitted ... so its gotta be a gear up or a multivar fitted. but bottom end preformance doubled , 0-30 swift as hell 30-40 swift to then im at max rpm and it just dont go no futher , downhill 47 but its ragging like hell ( still staggered 6g and 8g rollers)

 

i found this thread where a member goes and makes a sym jet custom manifold

so yep next on cars is to fashion a base plate over the reed cage and then some way of mounting a more modern flanged rubber manifold so i can hold non flanged aftermarket carbs.

tried looking for a set of main jets for my sym carb and its like smashing face on a hot expansion chamber. the manual does not state the length of jet or the screw size, and i found jets in 5mm and 6mm size and 6mm long or 7mm long

 

Gave up making a manifold. new plan of action

purchased a naraku 17.5mm carb with the funny looking flange thats a direct bolt onto the restricted manifold on the sym.
going to then dremmel the inlet area that 14mm out to around 18mm ID with a scooping flow to 14mm somewhat compressing the fuel/air flow as it travels down into the reed block.

going to see how if that changes anything first, if so i may then remove manifold and open up the exit where it flows into the reed cage a little. as the sym jet manifold is just a hawking long pipe with 2x funny angled bends i am unable to find a reaming tool to bore out the manifolds ID along the tube. but going from 17mm to a flat edged 14mm flange is not a great idea hence the re-working of the flange area on the manifold inlet side.

it looks like a speedfight uses the same type of reed cage. if you look at a sym jet basix/eurox reed cage then look at a speedfight/speedake reedcage they have a funny looking shape to the outer edging of the cage. and the spacing holes look to be the same to. BUT its an expensive risk grabbing a doppler race manifold and reed cage for a speedy/speedake only to find out it will not fit then i am stuck.

body work is also getting some loving to, as folks may know it got rattle can sprayed in black by a young lad, a very poor spray job and not even sealed over so every wash the paint starts to flake away. i am fixing that problem with Vinyl car body wrapping in a sweet chrome Orange.

also may have chance to grab a new scoot (a speedy 3 125cc stolen recovered) but the chap wants to see Pedro finish before he wants to do a straight swap ( really like pedro and i would like a 125 but im torn between pedro and a fourstroker let alone a stolen recovered )

 

with all the problems your having , and the money its costing you, it might be time to think new bike

 

i thought about a new bike, but i just will not make back what pedro has cost me , and with its ongoing problem at the mo i just cannot pass it on to some young lad like this knowing it will break down and leave them stranded. ( but i am looking at trying to source a poorly Aerox or the likes cheap as a replacement )

i been doing some digging about to.

1999 -2003 sym released the sym jet 50cc, a 49cc scooter running a carb to cylinder setup, the basic X look with headlamps that resembled the italjet formula. in this yeah span they also released the sym jet 100cc but it stopped at 2003 with no more 100cc models being produced. ( model 1) Non EU models came stock with a 17.5mm carb , EU models came fitted with a 12mm carb

2003 -2007 sym changed the cosmetic look of the jet 50cc and went with teardrop styled lamps they also came out with a second motor in the T5c range, this engine had a carb to crankcase setup and they renamed the scooter the jet eurox. they also came out with the sym red devil the only difference here between the devil and the eurox was the devil had 10 inch wheels. all other models has 12 inch wheels. ( model 2 ) again non EU models shipped with 17.5mm carbs where EU models came with 12mm carbs.

2007 to present day , sym then released the sym jet sport X , a total revamp on the jet 50 and jet eurox, its lines were more angular and so the whole body panel set changed and would not swap over to the more younger model versions but the motor stayed some what the same a t5c motor but with changes . these came the same as above EU version 12mm - non EU 17.5mm carbs

Now pedro has model 1 and model 2 looks. it has model one body set and a model 2 second edition motor fitted, with 12 inch rims the loom is a model 1 with a single front lamp output ( where model 2 has a dual lamp bulb setup ).
i have found that the peugeot speedake and the honda dio 50cc range also look to be using the same type of manifold bolt pattern but cannot be 100% sure on this. the reed cages look very very alike to the sym jet 50cc and the jet eurox 50cc.

i even when and trawled around some overseas sites, and have noted that some asian riders have dropped in 4t GY6 motors as a replacement for the 2t T5C motor ( looks like they are making up modded engine hangers to do this ), i also trawled to see if a honda Dio verti motor could be fitted to the sym jet 50 - eurox but could not find any documentation ( a dio powered sym would be great more easy to source parts for dio motors than the odd ball T5c motor sym produced ).

Anyways i am just waiting on mr postman to arrive with the new naraku 17.5mm dello carb , a short ride today with very very short WOT and i came back home to a very hot bike , you could smell the motor was overheating so i am hopeful the new carb will help this overheat problem / lean wot with a larger jetting up and that bit extra fuel in the cylinder , even with the uk weather being mildy cold the motors taking a bashing with this hot running more dense air would make the scoot run more rich but this is not the case here.
bike shop has upped its labour costs to £48 an hour so i have set a maximum 2hr labour on getting pedro re-jetted ( its a shame they do not have a dyno it would be half the time if we could dyno pedro to rejet it)

 

good luck but in my experience its time to stand back and take stock of you spending
cut your losses get a new bike
its taken me 30 years to learn this so I don't expect you to take any notice of me for a good few years yet

 

I have the bike shop looking out for a new bike if they have one come in , gave them my max spending for a bike. they are trying to flog me an aprilla mojito 125cc , but i kind of turned it down at £675 and i am not a retro style liker

i know im flogging a dead horse but i am smitten with the jet , i want a new bike but i do and do not want to sell the jet.

 

get a new bike and get about with out any more problems, mothball the jet and work on it as and when you can afford it

 

think i will but , i have to save up and that means the jet still needs to be done so i can get about on it.

 

theres o per cent interest deals on a few bikes at the moment