250F Another 2004 KX250F Project/Build

[Trfsrfr]

It add extra air to the intake charge to make it leaner. Most of the carb 4 strokes end up having extra fuel in the system when they die suddenly and thus the hot start was added just for this.
FYI: Three turns out on the fuel screw indicates you are jetted lean in the pilot circuit of the carb.

Paw Paw

Thank you @PawPaw.
I was thinking the same. The bike runs nice when choked. I had intended to buy a larger PJ, and did buy two of them, but apparently I bought the wrong ones.
I'll pull the float bowl and take another look, and make another order. RMATV should love me by now.

 

[Trfsrfr]

Okay, pulled the PJ, it's a 50.
So some questions to the guru's (and a big thanks to @SRAD97750 and @Myhilo for the lesson from months ago, but just now learned);

1 - How much does the PJ control idle to off-idle throttle input, and if screwed all the way in should the bike die? I.E - meaning it completely closes the fuel entrance into the cylinder? I remember kicking this thing into oblivion months ago and it wouldn't start without carb cleaner...

2 - If it entirely cuts off fuel when screwed all the way in, would it make sense to put in as large a PJ as available, then possibly just turning the fuel screw out maybe just a 1/4 turn (or whatever) to make it run?

3 - I have a 52 and a 55 in the parts box, both ProX. Which one should I install?

 

[Mihylo33]

Okay, pulled the PJ, it's a 50.
So some questions to the guru's (and a big thanks to @SRAD97750 and @Myhilo for the lesson from months ago, but just now learned);

1 - How much does the PJ control idle to off-idle throttle input, and if screwed all the way in should the bike die? I.E - meaning it completely closes the fuel entrance into the cylinder? I remember kicking this thing into oblivion months ago and it wouldn't start without carb cleaner...

2 - If it entirely cuts off fuel when screwed all the way in, would it make sense to put in as large a PJ as available, then possibly just turning the fuel screw out maybe just a 1/4 turn (or whatever) to make it run?

3 - I have a 52 and a 55 in the parts box, both ProX. Which one should I install?

1 the pilot controls the fuel from idle to just over 1/8 Throttle. The fuel screw doesn’t entirely shut the fuel off but acts more like a fine tuner because keys don’t come in .010 increments and you would kill yourself trying to figure those out.

2: see answer in 1.
3: 52.

 

[Trfsrfr]

Put in the 52, it didn't fire.
It's so damn humid here right now it's gonna sit for awhile. Plus I gotta Softail that the rear hub needs to be heated with the Oxy/Acetylene torch to get the brake rotors bolts out, my buddies 2000 Silverado in the driveway that needs a new head, a home security system that needs to be installed, and all new door handles/locks that need installed. AND, since the psycho ex is suing me in court again, I get to go spend some time with a psychologist and take some tests...
Glad I have August off work.

But YZ250F bud came over before Payson trip and said "Damn this KX looks awesome with those graphics on, it looks brand new".
So at least I got that going for me, lol.

 

[Trfsrfr]

Alright, looked the the manual today and turns out...it's right!
Spun the fuel screw in all the way, then backed it out 2-1/4, and she fired right up.
Took her a lap around the block and she is going to the track with me this weekend.
With the exception of the forks seals, it's a brand new bike.

Bringing the kids 125 with though, just in case.

 

[Trfsrfr]

Im doing the fork seals on this thing and am wondering about the washer that is by the seals. It's not a flat washer like I'm used to, but a thicker one with a machined out inside part.
I went to put it back in the same way it came out, but it doesn't look right to me, and I'm wondering if the reason the seals blew out a few weeks back was because the previous owner possibly had it installed backward???

Does the machined part of the washer face the top or bottom of the fork?

Does the machined surface hold the bushing in place??? The oil seal definitely wont fit inside of it.

When put in the way it came out, it doesn't look like there is enough space for the oil seal to fit inside the tube below the snap ring groove, which is why I'm thinking it was installed backward. The manual isn't very helpful...

 

[Trfsrfr]

Got it handled.

 

[Mihylo33]

Im doing the fork seals on this thing and am wondering about the washer that is by the seals. It's not a flat washer like I'm used to, but a thicker one with a machined out inside part.
I went to put it back in the same way it came out, but it doesn't look right to me, and I'm wondering if the reason the seals blew out a few weeks back was because the previous owner possibly had it installed backward???

Does the machined part of the washer face the top or bottom of the fork?

Does the machined surface hold the bushing in place??? The oil seal definitely wont fit inside of it.

When put in the way it came out, it doesn't look like there is enough space for the oil seal to fit inside the tube below the snap ring groove, which is why I'm thinking it was installed backward. The manual isn't very helpful...

View attachment 32724

Those are just extra parts that the manufacturer likes to throw in there to confuse bike owners so the dealer can service instead.
I always refer to my manual for assembly questions and really any questions about any of my bikes service related issues. I have found the internet to be outstanding resource for information on new products, tools, equipment and Brazilian midget fart porn. However when it comes to servicing the only credible resource is a manual.
@timoyz loves a good manual. :boner:

 

[PALMER84ONE]

Those are just extra parts that the manufacturer likes to throw in there to confuse bike owners so the dealer can service instead.
I always refer to my manual for assembly questions and really any questions about any of my bikes service related issues. I have found the internet to be outstanding resource for information on new products, tools, equipment and Brazilian midget fart porn. However when it comes to servicing the only credible resource is a manual.
@timoyz loves a good manual reach-a-round. :boner:

There...

 

[Trfsrfr]

It's all good, fork seals are done. As you said Mike, YT was very helpful, but took some digging to find the right video.
Took the bike around the block and she rips.
Cant wait to get to the track on Sunday, have both the yz125 and the kx loaded already...gotta feeling the kx is gonna sit more than she rides...
Loving that YZ125.
The yz250 has been collecting dust...

 

[Trfsrfr]

Took the bike to the track last weekend. She is very fast and very powerful according to another KX rider that rode it. It still starts hard though so I decided to call Hotcams. They directed me to Tokyo Mods in CA.
Called them and dude told me that there is an o-ring in the mid body of the carb that is glued in, and that the glue breaks down and plugs the pilot circuit. And of course they could set-up my carb for $250.00, or sell me the o-ring kit for $40.00.
I've had this carb apart 6 times already and I'm pretty damn sure that pilot circuit is clean, but...
Another guy at the track who is apparently a well known guy around these parts (his son owns a TM dealership) who has a lot of experience with these year KXF's, says that they used to have to raise the carb float height more than recommended.

Anybody have any experience with the above?

 

[Mihylo33]

Took the bike to the track last weekend. She is very fast and very powerful according to another KX rider that rode it. It still starts hard though so I decided to call Hotcams. They directed me to Tokyo Mods in CA.
Called them and dude told me that there is an o-ring in the mid body of the carb that is glued in, and that the glue breaks down and plugs the pilot circuit. And of course they could set-up my carb for $250.00, or sell me the o-ring kit for $40.00.
I've had this carb apart 6 times already and I'm pretty damn sure that pilot circuit is clean, but...
Another guy at the track who is apparently a well known guy around these parts (his son owns a TM dealership) who has a lot of experience with these year KXF's, says that they used to have to raise the carb float height more than recommended.

Anybody have any experience with the above?

James had an 04. All of his stuff was set to stock spec if I remember correctly.

 

[Trfsrfr]

Got the starting thing down now, I have zero problems anymore.
But the rear shock is shot.
So my questions are:
1 - is the Pivot Works rebuild kit good? It's on its way.
2 - How do I know what spring is in it? The one currently installed is white (thats all I know about it), and I'm assuming its not for a 190lb guy.
Race Tech recommends a 5.4...

 

[Mihylo33]

Got the starting thing down now, I have zero problems anymore.
But the rear shock is shot.
So my questions are:
1 - is the Pivot Works rebuild kit good? It's on its way.
2 - How do I know what spring is in it? The one currently installed is white (thats all I know about it), and I'm assuming its not for a 190lb guy.
Race Tech recommends a 5.4...

what rebuild kit? For bearings or is it for valves and seals?
By shot you mean leaking oil or threats slop in the bearings and linkage?
There should be a stamp on the spring some place usually on the ends if it’s aftermarket. Oem uses dots to confuse everyone.

 

[Trfsrfr]

what rebuild kit? For bearings or is it for valves and seals?
By shot you mean leaking oil or threats slop in the bearings and linkage?
There should be a stamp on the spring some place usually on the ends if it’s aftermarket. Oem uses dots to confuse everyone.

Bearings and linkage feel alright at the moment.
Rebuild below;