I have been reading threads and getting advise off the forums here for a while now. I've did all the minor destricting mods like remove intake and exhaust restrictors and took out the piggyback pilot jet and had the head milled to .045 as well as changed the plug to a 5. My question is, with this setup where should I position the needle clip? Thanks

soon to come-k&n filter, rejetting, and a pipe (maybe CTs pipe) haven't yet desided, any other suggestions?

 

i read that this guy put his circlip all the way up
I will be doing the same in a couple weeks,how did your
quad do performance wise after you did your head
and pulled out the intake pipe spcer, I also
went with the pro circuit 304 pipe it fit perfect
it picked up the lower and upper end, go to
Fri june 10 2005 that where your info is. do you
know about the gearing and where I can get a rear spocket
i went up three teeth on the front before i started my mods
thanks

 

Patriotsprockets.com should have some sprockets to choose from.

I had an 05 KFX50 with all of the mods and it was quite a big difference for sure, but no matter how much you put into the atv it will never be as good of an investment as buying something like a DRR DRX50.

I speak from first hand experience....The LT50/KFX50 is a great bike for a child that is small, but it's shortfalls make it very abusive when it comes to the suspension. It is $600-$700 for a Works set up to help minimze the harshness

Wheel spacers combined with Carlisle Snow Hogs really made it a lot more stable though...

We used the CT Racing exhaust (great people and great product) and intake set up.....I believe that we had the needle clip 1-2 spots lower on the needle (more fuel in) along with the National port and head work from PR Racing(very happy with their work) in OH.....Run the BPR7HS plug for the increased compression. The main jet I believe was a 67.5 after all the mods....Uni Filter model number I believe is a UP-4125ST (Universal Pod type 1 1/4" opening) mounted on the CT Racing intake adaptor(it comes with a K&N style, but I prefer foam)

The gearing was +3 on the front and stock rear sprocket....Great top end, but not much bottom to speak of...

CT racing Kit $375
Head Work $75
Port Work $275
Spacers $75
Sno Hog/Douglas Wheels $225
Sprockets/Chain $75
Wiseco Piston Kit $100
Time and Effort (too much to list)


For all of the money invested I could have almost had a DRR DRX50 ($1,899 at Kool Kidz)which is "many" times the bike....

Just sharing my first hand experience and advice.....I was given the same advice and didn't listen....Well thousands of dollars later I have a DRX50 and have nothing but positive things to say about it.

Keep in mind that many tracks will not allow most of these mods w/o putting your atv into a modded class and then it is just dangerous to have the KFX/LT out there....(if racing was ever your intention)

Good luck with your quad and please feel free email me for any mod info on your quad.....I was determined to make ours go fast...I succeeded, just not very cost effective in the long run

As long as the kids have fun and are safe, it is worth any cost and/or effort. IMO

 

I mite get the port and polish done later
but i am taking .045 off the head and jetting it
i'm going to run a 5 plug and i'm going with
a 70 main jet i was talking to a guy at the race
track and he said to go with the stock frt spoc
and go up 3 or 4 to make up the low end
you sound like your pretty good with this 50 quad
so in your opinion how my idea sound. I will be putting the
k-n filter kit from ct. my son is done racing this quad this year
he wants to move to a dirt bike next year so i don't want drx 50
even know it's a bad little fiddy Thanks

 

also what about my pipe i was told that to is a great pipe

 

The Pro Circuit pipe should be perform similar to the CT pipe I'm sure...


I searched through some of my old posts and found that that the main jet with all of the mods is either 75 or 77.5.

Once you let more air in the quad will run lean with a 70 (depending on elevation)...

That 5 rated plug will be way too hot for the engine....I strongly recomend the 7 rated plug for the higher compression you created with milling the head.....

If you go up on the rear sprocket you will gain low end, but the end may be work too hard all of the time.....That is why I changed the front sprocket.....to keep the engine from revving out so much....

I also blocked off the the oil injector (going into the cylinder-carb plug or fitting) and ran premix at 32 to 1 using a premium oil (Motul 800) This helped a lot.....

You should be good with your plans.....Just try to work with the jetting and the right temp rated spark plug or you will need to buy that dirtbike even sooner than expected.....Heat and and lean mixtures will equal a large yellow/green paper weight.

Trial and error will be the true test for what you are looking for, but please heed the spark plug and jetting advice....You owuld be better to error on the safe side in my opinion. (check other posts and you probably find that almost all of them use the 7 rated plug)

Good luck and keep me posted on your progress

 

how did you cut out the oil injection , I will go with the #7 plug
what about the drilling holes in the back of the airbox
what is the diff in ct head and shaving .045 also where can
I get a high compression piston for the shaved head
the main you said go with a 75 where can i get those
and what does ct have for there jetting kit

 

jetrus.com has a great selection of jets

Milling the head gave you high compression so the stock piston is fine....Wiseco has a std size replacement kit that is a little lighter than stock

The oil injector is blocked off by putting a rubber cap on the fitting that comes out of the side case (opposite pull starter) and is connected by a rubber hose to the cylinder.....putting a plug on the part that goes into the cylinder as well...A carb vaccum type plug will work.....If you take the cylinder to a machine shop they can put a plug into the cylinder, but it is not absolutley neccessary.

Main jet testing---I put the a big enugh jet to have it cut out on the top end and backed it down 1 size (75 should be a good start)

The CT intake kit is a metal tube that mounts to the carb and allows you to mount a universal pod type filter or the K&N style the kit comes with.

If I remember correctly I move the clip 1-2 notches down on the carb needle to allow more fuel on the bottom end

 

what can be done to a stock lt50 as far as ajustments that can be done to get more bottom end ?

 

There are 2 restrictors (exhaust and intake) plus a piggy back jet in the carb.

Remove all 3 and it should help you w/o any major mods or spending any money.....


Exhaust Restrictor- In between the cylinder and the exhaust pipe (looks like a washer)

Intake Restrictor- In the arm between the carb and cylinder(Thick washer with a slit in it-this may be able to be removed w/ a large flat head screwdriver or may need to be heated up w/a torch first)

Piggy Back jet- Not the big main jet....Right next to the main jet there are 2 jets that are stacked on top of each other.....remove the small one(the one that can be seen- not the one that is under it)