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tricky1961

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HI guys my sons mate has blown the g/box in his 125 loncin its allso getting very smokey so i think its time to replace it, id just rering it but since 2nd n 3rd gIMG_0867[1].JPGear's are shot be cheaper n less time consumingto replace it i dont know the brand of the bike only its 125 loncin engined what other brand donks will fit in with out having to modify any thing and is this motor a china buit one allso where the cheapest place to get a flywheel puller and chain breaker cheers tricky plus its gota very nasty oil leak on the l/h side on the bottom of the maggy case any info much appreciated tricky
 
yeah they are made in china.


here's an electric start 125 Lifan, about $315 delivered
Lifan 125cc Kick Electric Start Manual Engine Motor PIT PRO Trail Dirt Quad Bike | eBay

is he still using the electric start ?

this is a kickstart only Lifan 125, $249 inc delivery
125cc Lifan Engine 4 Stroke Kick Start Manual Clutch Dirt Bike Pitbike Motorbike | eBay

420 Chain Breaker

what did you want the Flywheel Puller for ?

there is one for the electric start engines, and another for kickstart
the stator for the electric start engines is bolted to the ignition cover, in front of the sprocket, so comes off with the cover.
 
actuly i ment to asy magneto/flywheel puller to get the to the stator to replace it you can see where some one has all ready tryed putting something between the magneto/flywheel and the crank case to try n pop it of the crankshats n the crank has marks on the thread where they laid into it with a steel hammer at least the could have used a wooden block or copper headed hammer if they didnt want do do it properly n not damage the theads
 
yea i showed him the motors on ebay n he only needs the kick start motor but his mate is doin a straight swap for another bike in 3 times better condition than his but has a dud stator he thinks we are looking at it to ninght n i told him it could allso b a crook CDI unit n i got a couple new units n soon as we get it home il try one n see if that fixes it before we go changeing the stator thats about the only thing i dont have spare atm lol
 
if the CDI swap doesn't give it spark, and have a multimeter you can test the Stator

unplug the stator wiring where it joins into the main loom,
set the multimeter to 2000 Ohms,
the readings you need off the Source Coil are from the black wire w/red stripe and the green,
it needs to read close on 380 Ohms

then set the meter to 200 Ohms,
to test the small Pickup Coil on the outside of the Flywheel, test the blue w/white stripe wire and the green, it should read 130 Ohms


if either readings are higher, or you don't get a reading, then that could be the problem
make sure you get a good/clean contact on the terminals, and hold the test leads firmly against them
(i can give you the reading to check the Ignition coil too if you need them)




an Electric Start Engine uses a different Stator plate to a Kickstart Engine.
on the kickstart engines, you don't need to take the Flywheel off to change the Stator.
it bolts to the inside of the Igniton Cover.
so it's just a matter of taking the l/h side cover off the engine and the Stator will be inside that
 
thanks thats a big help il print it off n put it up on my work shop wall for further reference be great to get the coil readings as well il just have to dust of the old multi meter u guys rock
 
to check the ignition coil.
this tests the Primary Windings of the coil, set your meter to 200 Ohms, put one lead to the earth point/terminal on the coil
and the other lead to the + power terminal
you should get a reading around .7 or .8 Ohms


now set your meter to 20k (20,000) Ohms,
this tests the Seconary Windings, take the Spark Plug Cap off the end of the coil lead (the spark plug cap unscrews anticlockwise)
put one lead to the + power terminal,
and the other lead needs to go to the wire inside the end of the coil lead
you should get a reading somewhere around 3K Ohms


if you cant get a reading then try cleaning the terminals and earth points,
and if you get a dramatically higher reading than what is above, then it could mean the coil is faulty.
a winging inside it could have arced out on another
 
there are some exceptions to the readings i have posted above too.
all china coils are not made the same, or share the same specs.

in warmer weather you will get a slightly higher reading off a coil too, but it's only about 3% higher
the opposite happens in colder weather too.
 
hi i tested the stator today had to get a new multi meter as my old one 25 yrs old crapped its self jaycar sold me a realy good 1 n auto rangeing so i didnt have to set it only to the ohms setting
source coil readine was 365 ohms n on a 125 elec start that has a good stator in it n it runs got a reading of
625 retested it 3 times n got roughly the same reading on all readings
small coil reading was 113.9 and on the other bike it was 140 .2 n retested 3 times n got similar readingsIMG_0931[1].JPGIMG_0930[1].JPG are these readings ok for benig a bit low or the higher in the bike that go's allso any idea's on how to remove the phillips head screw on the statorthats been butchered cheers allso if you look at the pic of the windings the chord that wrapps around the copper winding its all comming off the winding its self is ok what would uyou recomend to do wit it cheers tricky
 
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if the readings you got off the running engine were close, and it does spark and run, it sounds ok.

the best way i have found to remove a butchered screw is to find a good centre punch with a thin pointed tip.
place the point in between the slots of the screwdriver slots, about 3mm in from the edge, then tap it into the head a little, then angle the punch so you can tap it with the hammer, in an anticlockwise (at the top) direction.

it should work
if it doesn't then you still have another 3x areas to try.
 
do you have an impact screwdriver?
you may be able to loosen it with a flat blade bit ?
 
yea took to go's to get the screw out but finaly got it luckly the bottom screw wasent buchered had an old rolling frame n put the eng in there to test it b4 i put it in the bike thats got the shagged oil rings n turned out 2nd n 3rd gears wernt the prob the motor has rubber bushes in the eng mounts n the oil that was dripping down fron the exhaust pipe where it meets the muffler,thats how bad its burning oil, had perished the bushings n when he was changeing gears the motor was kicking side ways n makeing it jump out of gear you could grab the head n wobble the motor around it was that bad, the motor fired up straight away n no smoke to be seen was going to put it in the other bike but my son sold it the buyer took it like it was smoking like a 2 stroke for $180 offered to change eng but he said he wants it to be a project with his son i had several good 125 barrels on my parts shelf n run a cyl hone through it n came up beautiful n he getting piston/ring kit of ebay he allready checked prices n not that expensive thanks for your help tricky
 

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