Lifan Stator onto a YX ?

[DvDRip]

All the stators on ebay say suits 125-140 lifan, there's none for YX140. It looks pretty much the same but I just wanna double check with you guys if it's compatible
cheers

 

[SnItChY]

yup plug and play

 

[marty125]

can you put the lifan 150 outer rotor kit on yx 140's?

 

[headsmess]

yeah, just make sure the stator coils are the same... unless its a complete kit with the flywheel included or youll fry your cdi unit if you use the wrong flywheel with the wrong stator...

 

[DvDRip]

ok thanks guys
one stator has 2 coils and one has 5, is the one with 5 able to run lights and the other not?
and where would I buy and outer rotor kit? I don't see any on ebay

 

[Cactus Jack]

Which outer rotor kit are you referring to ? ... East50's , DHZ and 4322g on ebay sell Lifan 150 ORK's for around $85 + postage ...

 

[DvDRip]

my question about running lights was just standard stators, I'm comparing this

with this

just wondering if they are both capable of running lights?

I didn't know lifan 150 stator/flywheel was an outer rotor kit thanks for that, do you have experience with ORK's are they as crap as IRK's, I do lots of trail riding so don't wanna be stalling all the time and lacking torque

 

[DvDRip]

k thanks mate, I'll stick with the stock flywheel then,
I've taken it up some pretty big hills and yea it could use a bit more low down but I'm a bit intimidated by the whole cams/springs/ports modding stuff, but yea it's still good enough to anywhere I've tried so far

 

[headsmess]

the first one runs lights, and also makes a fair bit more current. ie, the headlight runs way brighter, using five coils. The taped coil is for ignition

the second one, as long as it has that "red copper" coil on the bottom, will run lights, but i found it cant keep up with my headlight, so basically useless....

they use different flywheels. i dont think kdf sells the complete kit. just the stator plate.

i used my "kdf" style flywheel on the dhz/pitster pro stator. ran, barely, wouldnt rev. then nothing. put the dhz flywheel for it on, still wouldnt run. tried a different cdi, ran. used the other flywheel again, wouldnt run... change back again... same deal...two cdis fried in the name of knowledge

the ORK with a larger mass will tend to hold the revs better maybe not rev so quick "no load" as an irk...

 

[DvDRip]

good thing you mentioned that headsmess, I would have assumed any standard flywheel goes on any standard stator

 

[DvDRip]

I was talking to mso and they sell a stator & flywheel for 125/138cc, they said it will not work on a 140. this is the same stator that's in my bro's 125 that I'm gonna try on my bike. does anyone know if this is a bad idea? I'll soon find out if fits like you guys say but I don't wanna damage anything. MSO mainly deals with 140 bikes so I guess they would know ?

 

[beccsptyltd]

id also be interested as to wether a 125cc ducar stator/fly wheel would fit straight onto a YX 140cc... Anyone?

 

[Cactus Jack]

I'd heed MSO's advice ! ... A 125 has a shorter stroke and lighter piston so fitting a flywheel off one to to a 140 could cause unforseen problems as far as balance and vibration absorption goes ...

There were a heap of people breaking cranks in the US and even though they said that it happened with a stock flywheel , in most cases they neglected to state that they had either fitted any old flywheel to their engine (YX150) , OR had altered the compression ratio with a high dome piston ... OR fitted a racing cam and revved the engine high and held it there (as in motard racing) ...

Anyone involved in racing should know that you never race a bone stock motor without having it precision balanced or balance checked within the intended rev range first ... It's also well known fact that it's not too bright an idea to simply swap out flywheels from engine to engine ... especially with an engine that's going to be thrashed ...

With Chev engines , you can't run a 350 (4" bore x 3.48" stroke) flywheel or harmonic balancer if you increase the stroke to 3.750" to build a 383 (4" bore x 3.750" stroke) ... the pistons and rods weigh the same as a 350's but their inertia has altered requiring both an off set balanced flywheel and harmonic balancer ... (externally balanced OR have the crank rebalanced using mallory metal slugs) ... It's also well known that stock engines are balanced to suit stock sedate daily usage ... IF you are going to change flywheels ... at least use one off an engine that has a similar bore x stroke ... There'd be a very sound engineering reason why Lifan used a different type of flywheel on their longer stroked 140's as opposed to their smaller bore x stroke engines ... and since they are using their ORK on the 150's which have a similar bore x stroke to their 140's ... they'd most likely work without encountering the unknown factor ... BTW ... Notice that Lifan steered clear of IRK's on their 150's and they have turned out to be super reliable , yet YX150/160's have encountered all sorts of problems running them ? ... ie broken cranks , clutches , slingers ...

 

[DvDRip]

ah k thanks cactus, I just wanna swap it temporarily to see if it runs properly with a different stator, not gonna ride it

 

[Cactus Jack]

It'll most likely start and run ... but a longer stroked motor can't handle as much timing advance as a shorter stroke motor so the 125 stators timing will be too advanced for a 140 ... especially since their compression is higher ... too much advance = shattered pistons , broken cranks , clutch baskets , kick starter gears , cases , bearings ... What happens is the crank gets flexed to hell when the piston has to compress expanding gas on the upstroke and that causes the ends of the crank arms to "orbit" with the flywheel and slinger on them ... effectively putting even the most precision balanced engine out of balance and that in turn makes certain people "THINK" that the crank broke due to the flywheels weight ... instead of rotating bending fatigue created by excessive crank flex ... most of the other damage is due to cranking speed detonation aka "kick back" ...

Stock flywheels are only pressed out and simply don't run true ... I would NOT use any flywheel for high rev use that doesn't have drilled balancing dimples on it ... Even Lifan 150 rotors run out ... BUT everyone I've got has been selectively balanced from the factory ... and the drilled dimples are in different places on each separate flywheel ... Loncin 120's also have the drilled dimples and YX finally has them on their latest 160 ORK ... But the YX factory still stuffed up with the timing advance tabs ... they were all over the place and the pulse pickup was fixed ... Lifan on the other hand made their ORK ignition fully adjustable ... obviously knowing beforehand that each engine would have different timing advance requirements depending on the fuel quality , jetting , rider weight , air temperature etc ...

 

[headsmess]

yeah, ill admit... i put the 125 stator and flywheel onto my 140 and it ran like shit(the gold type flywheel) it ran, but not too well...ignition advance, im guessing... jst...hmmm.... idk, sounded slightly wrong. but im definite on flywheel/stator plate combos, it fries the cdi...i even went to the trouble of frying my third cdi unit to be 100% sure about that...

i dont care, i just got a new stator from kdf sports, and the stock flywheels(black variety) back on, so it should be all good now...yet to put it back in a frame for the final test...

so, yeah, theyll fit, but note everything cactus said, theres balancing issues, and ignition issues to be wary of... like making sure the pickup coil clears the magnet on the flywheel for starters...can make a mess if youy overlook that bit...


just run it till it lets go and wear safety goggles

 

[Cactus Jack]

Does anyone really think any engine is so precision made that you can chop and change flywheels with a fixed / non adjustable pickup analogue ignition system and trust it to be right without checking with a timing light ? ... Come on ... the thought is ludicrous ... sheer fantasy ...

An over advanced engine will be sluggish and all the parts are getting strained fighting against themselves until something can't hack it anymore and Kabanga ... The damage can be as subtle as the engine blowing smoke in a very short period of time , blowing oil out of the breathers , kick back , jerking under load or when hot or with certain fuels ... Advancing the ignition actually causes an engine to run hotter ... and even IF the engine performs better (accelerates more rapidly) with higher static advance ... you are still stuffing it up at higher rpm ...

 

[DvDRip]

I bought the kdf style stator with flywheel tonight gonna put it on tomorrow and bike bloody better work or it's gonna meet the bin.
anyone want my old stator?