185cc GILFAX MONSTER MOTOR

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I'm interest in the same project :D

I have a import motor that i don't know the brand but bore is (52.4mm) and stoke (57mm). My piston pin is 13mm. My Valve are 24mm for intake and 21mm for Exaust.

I try to figure out what you did to your head but can't :(
new head ??

You what is the thickness between the cylinder/sleeve and the stud ?

Can you give me a part number for the piston ?

thx in advance
VeGeT
 
The motor cam from vinco already done. dont know if youve seen there work or not. But im impressed. The intake port is d shaped with a straight shot through the guide to valve stem. im happy with it. i just need to deck it.
 
not talking crap, i have seen their work on their 150cc biuld... put it together and run it.. see what it does. if you want more i'll help.
 
VeGeT said:
I'm interest in the same project :D

I have a import motor that i don't know the brand but bore is (52.4mm) and stoke (57mm). My piston pin is 13mm. My Valve are 24mm for intake and 21mm for Exaust.

I try to figure out what you did to your head but can't :(
new head ??

You what is the thickness between the cylinder/sleeve and the stud ?

Can you give me a part number for the piston ?

thx in advance
VeGeT
Click to expand...



here is the diference between the two heads. the one on the right should be the head you have, it has 24/21mm valves..... the head on the left has 30.5/25mm valves.. in the bottom picture i also stuck a 29.85mm and a 25mm valve in there for better reference.. your looking at 4-5hp in valves alone.. i don't know if i'll show any more port pics, but the differences only gets worse.

Picture118.jpg


Picture120.jpg
 
i'm going to put up one picture of the port.... might want to save this as i will erase it tomorrow.... this is a bad mother f er..

Picture121.jpg
 
Now not saying mine is as good as that but damn close. obviouisly not as big as my intake valve is 27mm. But when i said a straight shot through the valve guide to the valve stem that is what i was talking about. looks very similar. but that is a purdy site.
 
Damn its nice when something is done right! And when you said you would help that is menaing what?
 
run it, if you want more.... send to me and i'll get it done.
 
I know your is custom. And the motor will be back apart next week to drop in the 134 kit. So i know you have to pay for nice shit so what kind of price range we looking at?
 
that can very. i do have a few heads, maybe we can do an exchange. that way i can get it done so much faster.. let me think
 
I dont think you have a head to fit mine. Mice is a big valve with chinese spaceing and the bigger rods. along with a 69mm tall cylinder. 54x54
 
This motor work well ?
Doesn't over heat ?
How many hour he have run ?

Where can i find a piston 60mm ?
 
RK you have any of your seats come loose?
 
Mack said:
RK you have any of your seats come loose?
Click to expand...

as long as you don't have to weld close to the seat area you sould be fine.. i haven't had any of the custom seats do anything bad or wrong. please remember that we change out the stock seats.
 
Yeah, just wondering on the quality of the alloy in these Lifan heads and its ability to retain seat rings in their place. I know some have had trouble with custom seats hammering loose. I don't know what material they used for the rings or if they were aware of the need to find seat material which will expand close to the rate of the head.
 
with the porting pics i see that you have left the intake valve guide alone, and ground the exhaust guide down flush, is this the right thing to do as im sure i have read elsewhere that it should be the opposite, keep the exhaust guide intact and grind the intake guide flush????
whats everybodies experiences and thoughts on the subject?
 
I know this is an old thread but heres my 2c
As far as valve guides go i always leave them alone and port around them, for the gain in grinding them flat i see more advantage in a head that will last . Cant see there being more than a fraction of a H/P difference but a lost of reliability loss
 
yes i know this is old but most relavant and also dont like making lots of new threads if its avoidable
anyway, the problem with grinding around them is that you cant get the right curve behind the guide, also if you look at all the good high hp motors they always grind them down on either the intake or exhaust or both???
so what does everybody else think?
 
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