Atomik Prox X to Lifan 138CC Swap

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lerroy

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Hey guys

did a search couldnt quite find what i waned know

i have pro X 125CC ducar engine just wanted to up power and replace my worn engine i saw the lifan 138CC engine on ebay was thinking can i swap and put it in the pro x ?
if so how much work is involved ??

thanks guys any help wouldbe appreciated
 
i got a prox and i got a lifan 140 in the post and u need to grind the frame a lil so the clucth arm fits in.
 
thanks for the quick reply

how much griding is it close ? cool so its doable

well i think its probably a better option then getting another ducar..
 
Dont pay attention to Quick-ProX, He probably put the engine in up side down hence grinding the frame. The 138cc is actually 127cc and you will not feel much difference between that and your current engine apart from the fact that the 127cc is any gear start ( n1234 )
 
right so not really worth the upgrade cost prob best just working with the engine i have then....

thanks for info
 
Actually, you would feel much better acceleration even though it's only 2cc because the lifan has a better head (even though their both big valves) the lian has better ports..AND the lifan does not have the clutch on the crank, it has a oil sling on the crank instead..it's much lighter hense better acceleration..but the 140cc is a genuine 140cc motor (55.5 x 59)
 
isnt it a 140 cubic centermeters or somthin
 
it's actually 127cc, don't believe what the chinese say..lol it uses the standard 120cc monster engine bottom end with the 55.5mm crank, with a 54mm bore up bringing it to 127cc and not 138cc like they claim...th enew 140cc has a 55.5mm bore and 59mm stroke making it 141cc
 
hmmm so if i go the 140cc then ...have to look into it
 
to get the better motor you need to get a motor with rear pull clutch. The way we fit them is to actually grind the engine mount off completely and weld in a new mount that is in the correct position. We have done this to about 3 bikes now and it then will take a 138 or 140cc engine and we prefer the 138 kit as the power is higher in the rev range and less wheel spin issues. But the 138 kit is actually only a 130cc kit. In saying that we have a 138 kitted lifan that out guns the 140cc and is more fun to ride than the 140 bikes weve done. When the hop parts become easier to get then the 140's will be the way to go. I have some pics if you PM me
 
hmmm well wheelspin aint big issue :) would rather have more bottom then topend

so your saying 138 and 140 both need grinding to fit clutch in??

ill send pm cheers
 
i just fit a lifan 140 in my agb29 prox i just bent the clucth arm up and its fine. bending is easyer then grinding
 
is the motovert big bore outlaw a true 140cc then, on a barcode on the box it even says 149cc so yer i dunno.
 
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