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dude its fake it dosent look like a real GPX could be but i dont think so...
 
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GPX basically is a jailing, pretty much the same engine...The good thing about this motor is if you go big bore later on, you have a longer stroke then the lifan engines, and with the crank in the jailing/gpx you can fit a offset pin which will increase the stroke even more (lifan cranks can't be fitted with an offset pin) you could brink the stroke up to 68mm if you wanted.so longer stroke and big bore (57x57 for nice square engine) would be sweet..but they have the small valve head..not the big valve like the lifan head..so that's a downfall..but other then that. great engine
 
if you look at the pitster pro engines and then look at the ebay one you will know what i mean, thers no brand on the crankcase
 
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A gpx is just the same as a jialing, it's just badged diffrently buy the manufacters. you can't buy a "gpx" engine as far as i am aware..because they only came in bikes such as motovert, pitster pro etc..however it is EXACTLY the same as a jailing, just badged diffrent..if you look at motovert site, it says that their engines are JAILING
 
so you think i shod buy one of these insted of a lifan 125cc the grey one the good 1????
 
get a 140 if ya gunna get a new engine... only thing is it might be a bit to quick for the MXB's frame lmao
 
nah if i do buy a 140 it shod b rite.. but id stil lrather taht jialing/gpx engine if it beat a 138cc pitpro n demolished a pitpro 110cc then id ratehr that
 
it is just a 125cc its not that much different to a lifan.
 
I have spoken to the guy that is selling these motors !!! he has listed 1 before and the one thats there now !! The last one sold for $212.50.. The guy said that if this one doesn't sell for a good price he wont be putting anymore on ebay !!! He offered me one for $350 + delivery ($40) !!!

He said He guarantees these are Genuine GPX/Jailing motors which are the same thing !!...

He said that the name had to be removed as part of the condition of him buying the engines from his supplier as he is not permitted to advertise the name. !!!!

I would buy a GPX/JAILING motor over lifan or any of the other motors any day !!! These motors are far more reliable as the internals are far stronger !!! There are also kits available for them that make them a square motor 57x57 which makes it a 145cc motor !!! and if you like the big valve head it will bolt straight one !!!

I think you can even get a head kit which will take it up to 168cc !!!

but yeah I will be bidding on this same motor dude so you'll have a bidding war on ya hands right at the end !! HEHEHE...
 
You'll find that those motors are GT Jialings so they've ground the GT letters off to hide that fact . What a load of crap that they've had to grind GPX or Mojo off the side as part of a deal when the heading for the listing says - GPX 125cc Engine Thumpstar, Motovert mini dirtbike 50 - Ha Ha Ha !

IF they are hiding something , it can ONLY be that they are GT engines as I said above . Also , everyone raves on about how good the Jialings are BUT they forget to mention that they only run a pissy little 13 mm piston pin !!!!! Basically a 50 to 90 cc sized piston pin ! Honda runs 14 mm pins in the CRF 100 and CRF 80's . Why - because they need to be 14 or bigger to handle the load reliably ! A small pin might last in stock 8HP Jialings but start working them and see how long they last !

I say that the Jialings being better than Lifan story is a BS "myth" . IF they are so good - then why isn't everyone selling them instead of Lifan engines ! Why hasn't Jialing got onto the massive engine sales bandwagon in OZ to take a piece of the pie !

Where are all the gearboxes and engine spare parts listed on ebay for everyone to repair their "unreliable" Lifan engines with ??????? I see Lifan parts with hardly any bidders selling for crumbs - if all the BS was true - the parts would get flocked by desperate bidders wanting to repair their stuffed Lifan motor .

IF something is no good - it won't sell - word of mouth would kill its' sales off very quickly !!!!!!!
 
you could be right pb performance but i doubt wat that guy was saying is true as if they would have to take the name off the engine whats the difference with people selling lifan motors or ducar motors they dont take the names off.
 
The reason you don't see JAILING/GPX motors very often is because they normally sell for around $550us+ each !!! and not $250-$300aus like the lifan motors do !! This is why I questioned the guy about them being genuine GPX motors and how he managers to sell them so cheap !!! He said they are genuine and he wouldn't normally sell them that cheap and this is why he said if this one doesn't sell high enough he wont be selling anymore of them on ebay !!!

So with the lifan motors being so cheap what's the point in fixing one !! just buy a new one !!! I'm not dissing the lifan motors they are a great motor but I would buy a GPX/Jailing motor over one and its my right to do so !!

He only offered me the deal for $350 because I was hassling him hard about them and I missed the end of the auction so I hassled him again for his best price !!!

There's a guy in the states selling the Jailing motors at the moment for $285us and he is getting hassled hard buy the other resellers for selling them so cheap !! because they cant compete !! his reply is to bad I buy in bulk and can provide the low buy price !!! but he did say that once the current stock he has is gone, he will be selling them for the normal price !!!

either way, each to there own and buy what you like !!!
 
Quoted from Planetminis.com

the lifan 140cc are selling for around $350-$450 in the states and on ebay. they all come with an oil cooler. the only reason that mine didnt is because the seller ran out of stock of the 125s so he shipped me a 140 for the same price. his 125cc had an optional oil cooler which i chose not to purchase from him because i was able to find them cheaper elswhere.
Click to expand...

So that is around $425-$525us, for a Lifan 140cc. Usa don't have a high demand for china parts. Thats why they go so cheap down here in Aus.
 
For the last time, a gpx is the same as a jailing motor..

About the 13mm piston pin being unreliable, i have a stroker crank running 13mm pin, and it has held up for a while with me running my 149cc setup with my inner rotor and lightened oil sling, it's fine..maybe even more reliable because there is more meat around the outside of the conrod !!

The thing i'm saying is, basically you can bring a jailing crank to 59mm (spacer needed) 59.5mm (spacer needed) 60.5mm (no spacer needed) and if youre crazy enough 61.5mm (spacer needed) and 63mm (spacer needed)

So, that solves any modding for stroker cranks...cheaper then buying a new stroker crank or a jaling crank for your lifan (yes i understand the new 140cc lifan's have a 59mm crank, but they also have a longer cylinder and diffrent type piston..pistons canno't/not readily available at this moment)

Next thing, the jailing and lifan gearboxes are pretty much the same. The reason why people say "lifan gear boxes are crap compared to jailing!" is because of the shiftstar on the lifan's..ever since the lifan start in gear engines were brought out, the shift star had 1 tooth twoo steep, hense making the detent arm rising too high, and then taking longer to drop down to catch the gear, so it skips that gear (hense false neutruals from 3rd - 2nd)
That can be easy fixed, grind the shift star down or buy a new aftermarket shift star

3rd and final thing, the lifan engines have a big valve head (27/23) as opposed to the small valve heads on the jailing/gpx's (23/20) HOW SMALL HUH?! anyway..you can big bore the jailing engines standard, but unless youre running a big valve head, it's not wise to run it on pump fuel..so that said the conclusion is

Edit! one last thing, off the top of my head, the jailing has a 5 plate clutch, as opposed to the 4plate clutch in the 120cc/125cc lifan engines (the new 140cc engine has a 5 plate clutch) which should be less prone to slipping

-jailing has the stroker crank
-lifan has the big valve head
-same basic gear box, lifan shift star can be fixed easily
-Jailing has a 5 plate clutch rather then 4 plate like the 120 and 125cc lifan motors
 
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motoluver said:
Quoted from Planetminis.com



So that is around $425-$525us, for a Lifan 140cc. Usa don't have a high demand for china parts. Thats why they go so cheap down here in Aus.
Click to expand...

They go cheap in OZ because we are closer to China on the globe than the US is so shipping to here is cheaper ! I know personally because I've bought items from China that cost $5.00 registered post whereas the same item from the US cost me nearly $25 for registered post .

I've enquired many times with different sellers in the US about shipping an engine to here and they ALWAYS want $400 to $500 US just for postage alone - whether used or new !

The main reason why sellers and vendors want people to think that Jialings are better is because there is less money in it for them to sell Lifan 140's - they'd rather sell you a GPX Jialing that you have to toss the top end of away and flog you off a big bore kit , cam , and a big valve head . The end result is a GPX 141/146 hybrid that costs over $1000 US + and is no faster than a 140 with a cam and a bit of extra work .

Check out the dyno charts on this link - it has silenced all the GPX advocates - they have no answer - the thread stopped cold - the Lifan 140 makes more power and is a HELL of a lot cheaper to build :


Lifan 140 Dyno - Planet Minis Forum
 
Then there's the guy who went the GPX Jialing 140 with Lifan big valve head route - ported and cammed with a 26 mm carb and big pipe but was disappointed with his 13 HP result ! NOTE that he said the stock Jialing 125 produced 6.7 rwhp - whereas the other guy said his dyno showed that a Lifan 120 BVH engine produced 8.7 rwhp .

He learnt the hard way what drag , nascar , speedway , and formula 1 racers have known for decades - that a tall cylindered , long rod motor makes more overall torque , HP and revs than a short cylinder , short rod motor does !

The tall iron cylinder and longer rod in the Lifan 140 are there for a VERY good reason ! Do some web searches to find out what they do ! I've read Bill Jenkins' race engine books and they go into extreme detail about it all - they found it all out thru extensive and exhaustive dyno tests !

Another guy on Planet Minis said his GPX Jialing made MORE power with a bone stock Lifan big valve head and stock Lifan cam on it than it did with thE GPX head and a Crower G2 cam fitted !


140 GPX lifan big valve dyno - Planet Minis Forum
 
I dont know if I had to choose between a brand new lifan 140cc motor and Jailing 125 for the same price id go the jailing. Ive got a mate that imports and distributes his own bikes and races and his bikes have only been spec'd with the lifan motor because the number 140 sells more bikes and the motor is slightly cheaper. He reckons the jailing is the way to go.
 
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