Here's a link to the CT kitLink

 

Remove the oil tank, line and bolt that holds the banjo fitting to the engine case. Replace the banjo fitting bolt with a new bolt of the same thread about 3/8" long using one of the two aluminum washers from the banjo fitting and your done. Don't forget to use premix now!

Click here for the link to the parts being sold by the guy on ebay. I purchased this set up and it does make a difference, as much as the CT set up, probably not, but you can have the head milled on your own by a machine shop for about $25 and come close to the same power output at the CT kit, plus it's pretty quiet and the price was right.

 

Hey all! Back from another good weekend at the track with the LT50. 3rd on Sunday! This gives her another 2nd palce series thophy! My Kid Rocks! So whats my point? Point is that this is NOT a first choice race machine but with all of these mods and the right rider... this little bike can podium consistantly in a local circut. I deffinalty do not have the fastest quad at the track. My daughters class includes 50cc-90cc bikes usually 6-8 on the gate all toghether. Even against these bigger bikes though, she is consistatly in the numbers. When practicing we work on riding skills more than top end speed. For instance... got a bigger bike behind you? block and hold your lane untill the next whoop section then, because of the short wheel base leave em in the dust because you can go alot faster than them through these sections. Coming up on a turn with heacy traffic? Freak them all out by finding that three foot wide lane in the middle and blow by them as they brake trying not to hit eachother. I say train the racer because when you step them up to a bigger bike they won't rely on a motor that might throw them off beacuse all they learned in the first years was how to go fast.

anyway all this to say... not the fastest bike FOR SURE but compared to its bigger competition WAY more agile. This is a great bike to introduce a child to racing on. Depending on the CT Clutch and how my porting comes out I may even leave her on it one more year.

P.S. anybody got $ for shocks? Mommy won't let me cut high dollars out for the works set up. Taking Donatins at.... [img]i/expressions/face-icon-small-smile.gif[/img]

 

Update on the porting of the 04 LT50... WOW what a differance! I mentioned on another thread that I had done this but hadn't seen the bike on the track. I ran a good 5 or 6 laps behind my daughter at the track last weekend and noticed a massive change in mid range and overall top end power and speed. In the mids I saw that the bike can now pull out of a corner at 3/4 revs and hit top end a lot quiker. I also saw that when she got on and stayed on the pipe this little thing really wanted to run. A god example... Her brother rides a KTM Pro JR and in most of the turns she would blow by him like he wasn't there. This was not the case before the porting. One big change is hill climbing. Our track is a big outdoor national style track with many elevation changes and some big jumps on a climb. This big used to sound like it was working to get up hill and I could see a lag as she would lay on the throttle while climbing. This sickness is gone. Completely. Very cool to see.

Anyway long story short. Overall proting time two hours. Overall time working on the bike about 6 hours. Not that big a deal to do and really produces a great result.

 

Who did the porting for you? Has the CT Clutch kit become available yet?

I have done everything up to this point so far....I have a wiseco piston that I am going to put in to hopefully help it rev a little quicker.

Any word on a smaller rear sprocket? I put slightly smaller snow hogs on so I lost a little top end..

The quad surprises other riders that aren't expecting much from a KFX50 [img]i/expressions/face-icon-small-smile.gif[/img]

Any info is much appreciated


Also---What premix ratio do you run? I run 927 at 32:1

Thanks for the update

 

Me too. This has been a really fun project to think through. I have had a few offers on it but I think I will have her race it next year. So for now I will hold on to it.

I did the porting. I had the cylinder off because I thought I had a piston ring problem. Which I did not have untill I tried to put the piston back into the cylinder and broke the top ring.

Now I am NOT an expert but I did enough research and asked enough questions of local experts that I felt comfortable trying this. So Here is what I did...

1. Got out my Dremmel Tool
2. Began cleaning the inside of the exaust port untill it was cleaned but not altered
3. Intake, carb side... opened the round part of the port to match the opening on the intake tube. This was about 3-5 millimeters bigger overall. I carried this opening as evenly as I could to where the port becomes an oval and created the start of a good transition.
4. Intake, cylinder side... opened the oval down toward the bottom of the cylinder aprox 1.5 mill maybe even a little less I was nervous about ruining the cylinder so I ventured to be a little conservative. the rest of it I opend .5 to 1 mill overall. After I had made the transition good inside the port I used an 80 grit tip on the dremmel to rough up the inside of the port so gas will continue to atomize on its way in to the cylinder.
5. Exaust Port, pipe side... here again I started with the outside of the cylinder and worked my way in untill I had the start to a good transition to where the port becomes oval. I have the CT pipe so I opened the round part to match the opening to the pipe. I took out a huge amount of meat. Maybe 8 millimeters overall.
6. Exaust Port, cylinder side... I cut out the same amount of material as I did on the intake EXCEPT that I went up with the exaust opening instead of down. I polished the S#@T out of the inside of this port so that the exaust will leave the port as rapidly as possible.
7. Side Ports... I opened these both 1 millimeter at the entries and in untill they turn into the cylinder and left the cylinder side of these ports alone. I didn't and don't have a clear enough understanding of how they function so I figured I would leave well enough alone untill I learn more.
8. Cut all of my new gaskets to match the new opening sizes and put the whole thing back together.
9. I put a fresh plug in and will be pulling it on sunday afternoon to see if I need to jet up or down again. Currently I am using a .75 main jet. Wondering if I would be better of with an .80... figure that out sunday afternoon though.

Like I said before the result is a huge differance that is well worth the 2 or so hours I put into it.


Remember I am NOT an expert so if anyone else see's a flaw in the process or something that could have been done better. PLEASE speak up!

 

Sorry almost forgot. I use a swiss racing oil at 40:1, with a name I can't even pronounce, mixed in Trick 110 racing fuel. I am running the Trick because it takes away the dead spot this motor has at WOT. I discovered this while teasing a friend of mine about using race fuel. As a joke I used a tank and have never looked back.. The higher octaine has also really helped out this little motor.

 

I may switch to 40:1 to give it a little cleaner burn and I may try out the high octane fuel to see how it works....not like it burns it up too fast anyway

I sent the jug and head off to PR Racing in Ohio for their Port and Flow package......I am not brave enough to try to port myself....

I also will be installing a lighter stronger Wiseco piston as well

The "National" porting/perforamnce work is $245.......I was hesitant at first, but what the heck let's see what they can do with it


Keep you posted on the results.....


Maybe we can start a trend!! Most people here and at the races just laugh when I mention the quad my boy rides....

We'll show them!!!

If not...then I will pull out my 06 Honda 450R and beat them [img]i/expressions/face-icon-small-smile.gif[/img] LOL

 

Are you using the 2mill overbore piston? If so what does PR say about the overbore/ porting combo with an already milled head? Do they have a web site with a description of HP gains from this combo mod? If its good enough I may buy a new cylinder from Ronnies and try that.

BTW... ANYBODY laughing about your kid on a modified KFX is going to be saddly beaten if your kid is a good rider! Tonight we are going to the end of the year awards for our local circut and my 7 year old daughter is getting another second place season trophy to add to the one she earned for the summer series. In her class... 1 polaris 90 ridden by a 7 year old, 2 LT80's both ridden by 8 year olds, A heavily modified Polaris predator 50 ridden by a seven year old, a stock Polaris 50 and a stock lt50 ridden by 6 year olds. All these girls were at every race of the season. Along the way there were four or five other bikes in the mix. Proof is in the pudding?! Nope it's on the PODIUM!

 

Congrats on the great results your daughter earned on her KFX!!

If you guys ever decide to sell any of your KFX/LT 50 upgrades let me know! My 5yo son will be finding a brand new KFX next to the Christmas Tree in 2 weeks. I'm thinking that by next summer/fall he'll be ready for more power.