bigger camshaft for yx 160cc

[GTS221]

hi im new to the forums so i dont know alot about these bikes yet my motor is a yx 160cc and i want to get a bigger cam for it where should i look also can somone answer these questions for me.
do these motors have a rev limiter at all
should i upgrade the cdi
should i get roller rockers
should i get better valve springs
whats the max compression i can run im not worried about the starter breaking
is it worth porting the head
is a bigger exhaust worth it
if i machine the head how do you tension the timing chain and get the timing right

 

[sean01]

hi, and welcome to miniriders...

ok... for a cam upgrade i would consider getting the decompression camshaft that DHZ sell, it will also protect your kick start gears and cases from breaking
DHZ Mini Moto - PITBIKE DE-COMP RACE CAM DHZ D25 Grind YX 150,160cc

yes these engines do have a rev limiter which is controlled by the CDI. upgrading your ignition to this unit will make a world of difference..but dont go crazy with advancing the timing to much..
DHZ Mini Moto - RACING OUTROTOR KIT, ADJUST TIMING, SEMI-DIGI CDI, HARNESS

the valve springs should be ok, but i would be measuring them just to be sure...i havent seen alot of shops advertising springs for the yx heads tho im pretty sure they are the same springs as the lifan 140's...(dont quote me on tht tho)

if you wanted a complete upgraded head with rollers, bigger valves and ports and also bigger cam then this one would be good, but you loose the feature of the decomp cam which is the most important part needed.
DHZ Mini Moto - TB 150 160 Race Head V2 Upgrade Kit - GPX-YX150-160

max compression is determined by what fuel is being used, if you going to use normal pump fuel then leave it the way it is for safety. if you wanted to bump it up just a smidgen then you could machine the head down 0.5mm or change the piston for a hi comp version and machine the top of it down a little.

port work and bigger exhaust is all ways a good choice but dont go overboard with them...

 

[sean01]

lol i forgot the most important upgrade for these engines....
ditch the standard carb and run one of these.....just doing this alone would make the world of difference to performance..
DHZ Mini Moto - OKO 28MM FlatSlide Carby Kit 1/8 Throttle 160cc

you probly dont need everything in the kit so you could ring through the order and just ask for the carb, air cleaner and manifold adapter..oh and dont forget to get a jetting kit for tuning it

 

[GTS221]

ok ill get the carby first then it sais mine has a MOLKT Carburetor not sure on size i spose there the shittest 1? is the 28mm going to be big enough once i do the cam and head upgrade? also the decomp cam does that have as good performance as a normal non decomp upgrade cam? do they even make it lumpier whats the specks if anybody knows

 

[sean01]

28mm is boarder line to big for standard 150's and anything smaller..

you have a 160 and it will be awesome

 

[GTS221]

is there any boar kit to make it like 65mm? also are the four valve heads worth it?

 

[sean01]

^^^^both questions have been answered in your other threads...

 

[GTS221]

yeah thanks i started them threads after i asked in here

 

[sean01]

all good...