Freestyle 300 SX build FINISHED!

SUPERJET-113

GASKETS FOR CHAMP BRAP!
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We all are anxiously awaiting you to ride it and give the results! Good job on that long hard build. Thats a hell of a lot of work! It looks great man!
Have fun on your maiden voyage!
 
Im anxiously awaiting the end of the motor break in. Its going to be so hard not to beat on it and see whats really in there. I hope I can get 10 gallons through it tomorrow.
 
HAHA according to JetManiac I need to put at least 5 gallons at 20:1 no more than 1/2 throttle. Then on my 2nd 5 gallons at 40:1 no more than 3/4 throttle, change the plugs and then go ride it. (its going to be a long day)

Plate to plate??? I never rolled or tried a backflip before in my life. Nose stabs, fountains and jumping was the extent of my skills 2 summers ago when I last had my 750sx. When it was 951 powered last summer all it did was go fast and straight. Im out to learn this summer. I should have the baddest ski on the lake, but without the skills it wont matter what Im riding.


And tonights update, everything is ready except the pole limit strap and a new state registration. I fired it up tonight on the stand, no hose. Fired right up and hit the kill switch, and I didnt rev it up. WOW is it loud with no water! I dont have a flow control valve so I put a 2.0 main jet out of an old sled carb in the stinger tube before I put the hose on. Hopefully it dosent make it too dry and melt couplers.
 
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I just read the instructions for break in form JetManiac:

no more than 1/2 throttle for the first hour, run out the remainder of the first tank using 3/4 throttle or less.

the 2nd tank is mixed at 40:1, no more than 3/4 throttle for the first hour.

(these are for a stock superjet tank, Im running a 2.5 gallon kart tank)

So, 5 gallons to break in, and the first hour of the second 5 gallons. I should be able to do it all in an afternoon. Im off to get my new registration!
 
I rode it finally, no big issues to report. Only thing I forgot was the breather on the kart tank. I rode and got 3/4 of a tank out of it and the sides of the tank were caved in when it stalled out. Easy fix. Its really snappy, and seems to be moving pretty good at half throttle. I still expected more bottom end out of it, but I am still on my 20:1 smoke juice. Ill bet after I switch to 40:1 it gets better. So far Im really happy with it, I may try another hooker. I have a 10/16, How can I tell what direction to go on the prop? I also noticed my top and middle pipe screws were closed, I do remember setting the bottom one at 1/2 turn before I put it in. There is no way Ill ever reach that one without pulling the headpipe.
 
You need to really ride that thing before considering a different prop, Having that much oil dumped into the motor will result in sluggish feeling throttle, I bet when your done with break in and get at 40:1 and the carbs dialed in it will run like it is suppose to, Then you can decide which way to go with the prop, That set up should hit really good off the bottom.
 
I hope so, Dont get me wrong, it runs great! I was expecting arm jerking force when I hit it going into a wake. We will see what tomorrow brings with less oil. I looked at the plugs tonight, black and dripping with oil.
 

SUPERJET-113

GASKETS FOR CHAMP BRAP!
Site Supporter
I rode it finally, no big issues to report. Only thing I forgot was the breather on the kart tank. I rode and got 3/4 of a tank out of it and the sides of the tank were caved in when it stalled out. Easy fix. Its really snappy, and seems to be moving pretty good at half throttle. I still expected more bottom end out of it, but I am still on my 20:1 smoke juice. Ill bet after I switch to 40:1 it gets better. So far Im really happy with it, I may try another hooker. I have a 10/16, How can I tell what direction to go on the prop? I also noticed my top and middle pipe screws were closed, I do remember setting the bottom one at 1/2 turn before I put it in. There is no way Ill ever reach that one without pulling the headpipe.

Oh man your lucky you were just breaking it in when you forgot the tank breather. I had one of those YAM OEM tank vents clog on me once when I was riding the river on my SN SJ. I was going WFO, when it suddenly died. The gas tank was sucked in so bad it was like 4" wide! I had a real bad lean siezure and had to put on a new top end, and im sure the crank didnt like it either. I

I dont even run tank vents now, just a long piece of hose all coiled up so water cant go back in the tank.

Cant wait to hear more after you get it broke in. Good luck!
 
Can anyone give an insurance company that will cover this for what I have in it? I called my auto and home agent, they can only cover it for what is books for. I'd like to insure it for at least 10k since it will be living on a lift at the lake 1.5 miles from my home. My boat is there too, but this worries me.
 

SUPERJET-113

GASKETS FOR CHAMP BRAP!
Site Supporter
I wouldnt leave it there if you cant get it insured for what you want. WAY to easy to steal...
So they will only insure as a 300sx? How much is that? Like a few hundred dollars? lol
 
The people that own the place live there all summer, and dont work. So they can keep an eye, plus I keep it locked with a cable to a dock piling.

So, here is the latest. My break in is over. I changed the plugs, put in new gas at 40:1. I put about 10 min on the new gas and plugs and checked the pipe. We have an issue. The pipe is warm to the touch, no sizzle and I can hold my hand on it. I should mention my headpipe has some huge screws in it. (undisclosed to me when I bought it) They seem to be a coarse thread as compared to the ones fp puts in. Is it safe to say a half turn on the top and bottom is not the same as a half turn with a fine thread screw? I guess I have to pull the headpipe and mess with them. Not too happy. Maybe this would explain why the hit off the bottom is not what I expected? It screams up top.

And I really need to order a flow control valve, the carb jet on the stinger is not shutting off the water at low speed as JetManiac explained to me. Ill have one here by the end of the week.
 
I would think so, haviing a big bolt in there compared to the tiny fpp screw is a big diff when only half a turn out. That is letting alot more water through than the stock size, probably almost shut would be equal to the fpp screw. I would close it, and then just barely crack it open, What size is it?
 
Not sure of the size but the thread pitch looks like 1.5mm per turn. I would bet the stock ones are .5mm per turn. So the math on that one comes out to be 1/2 turn would equal .166 turns on the larger thread. Unfortunately I have to attend a viewing tonight for a good friend who lost his brother in a motorcycle accident, so I wont be able to make any changes until tomorrow night.
 
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