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stoozo

Banned Wanker of the Century
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So it looks like my 125 lifan is going to be in the bike for a while as I get other motors sorted out. A new smaller flywheel is already on the cards. What else can I do to get it running a little faster without being to crazy spending a ton of money? Links would also be nice as I just got the new comp and don't have any book marks any more...plus I suck and finding the best value stuff on eBay :thumbdown:

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bin it and buy this lol

NEW GPX 125cc Race Engine High Comp Piston Race CAM | eBay

for the amount you will spend trying to make your engine perform like the gpx, you really might as well just buy one.
a good light weight outer rotor kit has to be between 70 to 100 bucks, then you have to find h/d valve springs, cam hi comp piston blah blah blah im sure you get the drift.

sell all the engines you have bar the z160, and get the gpx!!!!!!! it seriously outperforms the lifan 150's anyway's so why bother fixing that dinosaur lol
 
if you are deadset on getting something out of that engine, you could check the clearance between valves and piston, and take a mm or so off the head. i dont no if thats possible like with cars, but that would give yopu a higher compression ratio and a bit more go...... i struggled to find any cams on ebay, only h/d valve springs, but ooracing may have something to suit your need.
 
Yeah I dont have the money for a GPX :thumbdown: one day maybe!

I think I just found a race cam on t-bolt for the lifans. Dunno I think craig might have somethign that will fit, remember he has 2 other parts 150s that both had cracked RH crankcases too...So not sure but this is it anyway! There is a possibility the outer rotor will fit from the 150 lifan :D

iirc it has a big valve head in the 125, but also a chance the cam fits from the 150 too :thumbup:

Hmmm wonder if anyone has done this before...trying to fit a bunch of 150 lifan parts to a 125 lifan...

TB Race Cam Kit for Big Valve Heads - Pit Bikes - Parts by Brand - SDG Parts - TBW9004 - TBolt USA, LLC
 
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that one is for yx engines, not sure if they are different or not? they are in america to so that would be a hundred bucks by the time it got here...im pretty sure 10 to 12 hp is your limit on those engines due to the clutch setup anyway......... you could grab a cheap performance coil and cdi ( the cdi's can be hit and miss on quality tho)

Performance Racing CDI Unit Coil GY6 125cc 150cc PIT Quad Dirt Bike ATV Buggy | eBay

and a splitfire lead

Foxico Splitfire Twin Core Racing Ignition Coil Lead 50cc 350cc ATV Dirt Bike | eBay

that, a oko24mm and maybe this gpx stator if it will fit, but you would still need the cdi which is around 45 bucks i think

NEW Outer Rotor Stator Magneto Seals GPX 125cc 160cc | eBay

i really dont see why you feel the need to persist with that 150, if so many have cracked there as well, then its very unlikely simply fitting a new case will fix the issue. they must have a design flaw in the casting, and their power output really isnt that impressive for their cubic capacity imo. maybe the couple i rode were duds i dunno....
 
that cam isn't long enough

stoozo already has an adjustable rotor kit on the 150 Lifan, so straight swap
 
then there is the use for that lifan ;) can you deck the head by 1mm on the 125's craig? or would he be better off with a hi top piston for it?
 
i really dont see why you feel the need to persist with that 150, if so many have cracked there as well, then its very unlikely simply fitting a new case will fix the issue. they must have a design flaw in the casting, and their power output really isnt that impressive for their cubic capacity imo. maybe the couple i rode were duds i dunno....

My thoughts exactly, I think I've pretty much decided it not really worth fixing as I'll always just be waiting for it to start slipping gears again. Pretty sure thats why 150 lifans are almost in non existence now!! That said the yx150s look almost identical :/ so thats off the menu also.

stoozo already has an adjustable rotor kit on the 150 Lifan, so straight swap

Woo hoo :thumbup: Do I need those electrics or will that swap too?

then there is the use for that lifan ;) can you deck the head by 1mm on the 125's craig? or would he be better off with a hi top piston for it?

That would be interesting to find out, that alloy machining place we dropped through the other day surely would do that for like $20-$30....if they do a v6 head for $65 :thumbup:

Would that work possibly Craig?
 
thats a much better deal :)

on another topic could i convert the 70cc to run one of those rotor kits? i no i would lose the electric tart but its just a thought...... sorry to hi jack ya thread already stu ;)
 
yeah, i'm 99% sure you can

i have a 110 here i took the flywheel off, then the electric start adapter plate, and then you can bolt whatever stator on.
but that engine is buried atm.
i'll let you know for sure before you are ready to get stuck into yours.
 
you need to measure your piston pin size first, just to make sure you order the right one.

adding a 54mm bore to your engine would make it a 127cc instead of a 119/120cc too
but then you need a different piston again
 
$20 if i can find it in my boxes of parts

Hmmm ill have a look tbolt look like they have some 54mm high comp pistons...although I'm thinking it might not be worth doing to much to an engine that old...but I suppose I do have the other one for parts minus 3rd gear obviously! Think I might just go the high comp piston if its a straight fit...

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it is a Barrel/Cylinder not a head

4Stroke_Cylinder_Block.jpg
 
Yeah it seems to be a bit harder to find hi-comp pistons in 54mm :/ having a look now and not much luck!

Might be more trouble than its worth kind of thing...
 
standard 54mm piston would till give you a little more torque.... i reckon the stator of your 150, the 54mm bore with a standard piston, head work h/d valve springs and the 24mm oko would be a noticeable improvement for a quite cheap outlay, the valve springs on ebay were only 10 bucks plus 10 postage i think, a piston and rings wouldnt be to much either......
 
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