lifan 140 vs YX 140

[DvDRip]

I took the clutch covers off a yx140 and a lifan 140 side by side yesterday, YX140 had much stronger clutch basket and longer springs, I don't know how to test the springs but they seem allot heavier than the lifan ones. The shift star seemed to be a much better design with less room for error. the YX kickstart gears were much thicker and stronger looking. YX 140 had a lightened oil slinger but ran a stock flywheel, I don't know if this a good thing or not but would help if you wanted to fit an ORK, the yx stator is absolute rubbish compared to the lifan one and that's about the only thing that the lifan had that was better than the YX.

Lifan runs the oil cooler from the crankcase close to the oil pump while the YX runs the lines form the head. The lifan should be getting allot more oil pressure and can run much less restrictive lines without the need for bango bolts, but then it has to pump the oil 3x further to the cooler. Cooling the head is more important than the crankcase but the lines on the head feed get in the way sometimes and can get very annoying.
So I'm undecided which cooling system I like more.

If I ever buy another 140 it'll be a YX for sure and just get an ORK to sort the stator issue. The YX is stuffed (my fault) so I chucked the better clutch in the lifan and might borrow the lightened oil slinger too, just not sure if it'd be worth it, but if I get an ORK for it I'll be swapping out for the YX slinger for sure.

hopefully one day I'll be able to split the cases on both side by side and see the rest of the internals but the Lifan doesn't need the cases split so stuff that.

 

[creole]

Nice.
1p55fmj right?

i noticed where the oil cooler banjo bolts into, if you look into the holes on the head, the holes dont line up %100, so the oil just pools up in that section of the cam cover.
For some reason oil leaked (pissed) out the gasket, it may have been poor surfacing or gasket? but ive sealed it up and is ok now after 10hours riding. All the yx140's are like this too. Not sure if its a flaw or they are meant to be like that?

also how does the oil flow up the oil cooler? i thoguht the oil slinger was just arms on the flywheel that throws oil around the crank? or is there a proper oil pump? Oil obviosuly got to the head and was enough to constantly flow out the leak of my motor!

yeah the yx stators dont have accessories like the lifan.

Does the lifan140 have a ORK/IRK? cos compared to the YX's they seem to rev like they have an Ork/irk

 

[DvDRip]

nah lifan 140 comes stock with a heavy flywheel and full power generating stator.
The YX140's came stock with IRK's but then they realized IRK's are rubbish and replaced them with heavy flywheels just like the lifan and s#!thouse stators, that's why they have a lightened slinger as stock.

they have an oil pump to the right underneath the oil slinger, I think the oil is pumped up through the head studs and galleries, if you take off the oil cooler mount bracket you can see the studs leading off to the oil cooler feed. and I agree the YX oil feed setup is very restrictive.

 

[sean01]

I took the clutch covers off a yx140 and a lifan 140 side by side yesterday, YX140 had much stronger clutch basket and longer springs, I don't know how to test the springs but they seem allot heavier than the lifan ones. The shift star seemed to be a much better design with less room for error. the YX kickstart gears were much thicker and stronger looking. YX 140 had a lightened oil slinger but ran a stock flywheel, I don't know if this a good thing or not but would help if you wanted to fit an ORK, the yx stator is absolute rubbish compared to the lifan one and that's about the only thing that the lifan had that was better than the YX.

Lifan runs the oil cooler from the crankcase close to the oil pump while the YX runs the lines form the head. The lifan should be getting allot more oil pressure and can run much less restrictive lines without the need for bango bolts, but then it has to pump the oil 3x further to the cooler. Cooling the head is more important than the crankcase but the lines on the head feed get in the way sometimes and can get very annoying.
So I'm undecided which cooling system I like more.

If I ever buy another 140 it'll be a YX for sure and just get an ORK to sort the stator issue. The YX is stuffed (my fault) so I chucked the better clutch in the lifan and might borrow the lightened oil slinger too, just not sure if it'd be worth it, but if I get an ORK for it I'll be swapping out for the YX slinger for sure.

hopefully one day I'll be able to split the cases on both side by side and see the rest of the internals but the Lifan doesn't need the cases split so stuff that.

^^^^^this is the reason i prefer a yx over a lifan. (you might have seen in threads where i say this)
the yx seems to have alot of upgraded (so to speak) parts inside it.

as for the oil cooling. it is said that cooling from the head doesnt allow enough cooling because the cooler's return line is going back into the head thus heating up again...

what i havent tried but i may one day, is feed the cooler from the head and return it back to the clutch cover. this of course would need a lifan clutch cover and i havent seen if they are compatible...i also havent looked into whether it would hurt the engine as a result of not having oil come back in to the head.

i am in the middle of a yx140 build. it is only a tame build and most of it used from parts left over from other engines i have....
yx140 cases and bottom end, yx150dt-5 crank(60.5mm stroke), boring the yx 140 bore to 58mm(seems the most it will go, and has a thicker sleeve in it than the 150's)
this will give me 159cc. it will also have the daytona style clutch cover and no oil slinger....and yes the clutch cover has provision for the oil cooler.

another thing i have considered but havent totally looked in to it to see if its do-able is running 2 oil coolers.... one feed from the head and returned to the clutch cover and the other feed from the clutch cover and returned to the head...
this would give cooler oil to both top and bottom of the engine.....

now lifans....hmmm im not even going to go there because i cant stand them...
i have seen 10 lifan 140's to 1 yx 140 fail...snapped cranks broken cases, broke kick start gears...yeah i dont need to go on, youve all heard it before.....

oh also i believe the yx 140 has a close ratio box...or at least different ratio's

and also you can buy IRK plates to add weight to them

 

[themountain]

i have seen 10 lifan 140's to 1 yx 140 fail...snapped cranks broken cases, broke kick start gears...yeah i dont need to go on, youve all heard it before.....[/B]
oh also i believe the yx 140 has a close ratio box...or at least different ratio's
and also you can buy IRK plates to add weight to them

well , my friend, I have eeeeeexactly the contrary opinion about the engines...yx140..better head design(no doubt) weak electrics, same crappy gear box....lifan140 useless cam...rest is pretty much par on every other chink engine(ducar,chaytona,piranha,etc)...my 153cc hold up two seasons without even touching the interiors(besides clutchplates)...can`t ask for more from a cheapa&& race engine I think.

 

[sean01]

well, i spose when searching on here looking for lifan 140 and yx 140 youd clearly see majority of the threads are related to lifan 140's breaking or needing repairs... very few about the yx 140 breaking and when there is its odd problem..

im not saying every lifan 140 is rubbish, sht i know of one that is about 2.5yrs old and the only problem it has had was the starter gears smashing...its still going today and with only 1 change of rings...but rattly as...

im looking at the ratio of dead lifan 140's to yx 140's....

 

[beccsptyltd]

Well ive gotta say my 140 YX has been going strong for just on a year now and have had no mechanical problems with the internals.. No unusual noises or anything!

she'd have around 100 - 120 hours on her now and yeah only ever changed oil and general maintenance on the good old 140YX