YX 140 engine mods

[bend1202]

i was wondering what the best mods to the yx 140 are. i've heard head work is where you will get most of the power. are there big bores for these motors? and what is the most HP you can get out of these 140's, and still be reliable??

thanks.

[Precision50]

i was wondering what the best mods to the yx 140 are. i've heard head work is where you will get most of the power. are there big bores for these motors? and what is the most HP you can get out of these 140's, and still be reliable??

thanks.

this question has been asked a few times recently check the search option....?

[HACKMUNCH]

can go 146cc or even 153cc if you find a good machinest. cam will get you another few hp, z40,tb300 takegawa r20, porting and so on, they can make 15hp all day.

[ThumperMx365]

Which of the cams mentioned give the 140 motors the Same type of power just more of it. I am looking at getting a cam but want one that doesnt change the power(IE more low end but takes away from mid and top and vise verus) but just adds more of the same type of power the 140 already has.

[HACKMUNCH]

TRAILBIKES honda race cam, think it's the tb300 on their site. has 230 duration and 6.88mm lift.

[Precision50]

TRAILBIKES honda race cam, think it's the tb300 on their site. has 230 duration and 6.88mm lift.

Not listed on the site as a TB300.....?

[T Bolt USA]

you need the tbwo300 cam and tbwo414 32t sprocket

we like this set up in gpx140cc motors

[bend1202]

so would this work?http://www.hondatrailbikes.com/catalog/product_info.php?products_id=866

and would i need anything else to make this install go smoothly? and what kind of HP gain would i be looking at?

thanks.

[rotax harry]

im lookin at one on ebay right now....

has a lightin stator...heck yeah!!

so....it should fit right in my mad max correct?

what is the engine length so i can make some measurements before i buy....

[Precision50]

im lookin at one on ebay right now....

has a lightin stator...heck yeah!!

so....it should fit right in my mad max correct?

what is the engine length so i can make some measurements before i buy....

all these motors (Lifan, Jialing (GPX), Yx and Zongshen) are all CRf50 based Case motors and will fit into any bike that has a Horizontal CRf50 based motor in it.

things that maybe needed:

Pipe, Wider foot peg bracket (most aftermarket work) different skid plate (when going from CRf to Yx) Longer or shorter fuel lines and longer throttle cables (usually) and possible that a bracket may need to be made (pipe hanger)

[rotax harry]

its a extended 50 frame

[SLAyER]

I just got done putting my yx140 together today and it rips. Got the head ported by AHP along with a tb300 cam and 32t cam sprocket. Also went with a thinner metal head gasket.