Author Topic: 2003 KX 250 SF Conversion  (Read 236778 times)

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Offline umberto

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Re: 2003 KX 250 SF Conversion
« Reply #210 on: January 17, 2016, 09:05:01 AM »
That's Great News! Do you know what needle he sent with the carb (4-2Xl,5-2Xl) ? Also don't forget if/when you get time, check the main jet block on the PWK (I am a Curious George  :roll:)

DoldGuy
i pulled the main jet block, and I think you were right on. The o-ring looks very ratty.

« Last Edit: January 05, 2018, 02:46:02 PM by umberto »
Perhaps I have a dirt bike addiction?

03 KX 250/88 KX 525/2017 KX250F - Goliath
17 KX250F/04 KX250
04 KX 250 - Lunchbox's Bike
05 KX 125/144

Offline umberto

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Re: 2003 KX 250 SF Conversion
« Reply #211 on: January 18, 2016, 12:54:12 PM »
I forgot my niece made this video of Goliath in action on Christmas day.  Not very long, but pretty good sound.

https://www.youtube.com/watch?v=14ahsC3W66o
Perhaps I have a dirt bike addiction?

03 KX 250/88 KX 525/2017 KX250F - Goliath
17 KX250F/04 KX250
04 KX 250 - Lunchbox's Bike
05 KX 125/144

Offline alexander-vmann

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Re: 2003 KX 250 SF Conversion
« Reply #212 on: January 18, 2016, 12:55:42 PM »
nice!
KX 500 newbie

my bike: 1993 kx500

Offline sandblaster

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Re: 2003 KX 250 SF Conversion
« Reply #213 on: January 18, 2016, 12:57:23 PM »
Yes!
The four stroke engine: That's one stroke for producing power and three for wearing the engine out.

Offline umberto

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Re: 2003 KX 250 SF Conversion
« Reply #214 on: January 18, 2016, 12:58:08 PM »
I can't wait to get a video with the new carb.  It sounds downright mean with the Lectron.   :mrgreen:
Perhaps I have a dirt bike addiction?

03 KX 250/88 KX 525/2017 KX250F - Goliath
17 KX250F/04 KX250
04 KX 250 - Lunchbox's Bike
05 KX 125/144

Offline umberto

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Re: 2003 KX 250 SF Conversion
« Reply #215 on: January 25, 2016, 01:06:58 AM »
I took Goliath out for a test ride on Sunday, and the carb is adjusted perfectly from open to 1/2 throttle.  It's very crisp and responsive.  Unfortunately from 1/2 to full throttle it bogs pretty badly.  Thankfully it's just some tuning on the carb and no major parts.  Foxx asked about the gas mileage, and it is pretty bad.  We made about 20 miles yesterday and I would estimate I used about 3/4 of a tank or more to make those twenty miles, and that was using only half throttle and lugging a lot.  I think the larger tank can't get here soon enough.

If you didn't read my ride story, the question of what stops a KX 500 was answered: The world's deepest rut.  Of course Danger had to get a couple of pictures of it:

« Last Edit: January 05, 2018, 02:46:23 PM by umberto »
Perhaps I have a dirt bike addiction?

03 KX 250/88 KX 525/2017 KX250F - Goliath
17 KX250F/04 KX250
04 KX 250 - Lunchbox's Bike
05 KX 125/144

Offline umberto

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Re: 2003 KX 250 SF Conversion
« Reply #216 on: February 05, 2016, 10:03:10 AM »
I am closing in on my final mods before I blow the bike apart, powder coat the frame, get Larry to add a decompression switch, and add graphics.

I decided to try new springs on my bike, because I felt like the valving was pretty close. I got springs from Race Tech using their calculator to determine rate. I like that the spring is blue to match the rest of the accents.



I haven't had a chance to ride it yet, but I hope to sneak out Sunday morning. I did some tuning on the carb to fix the full throttle bog, so I'm anxious to ride it.

I also replaced the terrible seat cover that came with the bike.



I found this air stapler at Harbor Freight Tools. It was $21.99, and had wider staples than the other stapler I had. It worked pretty well for the money and made installing the cover a breeze.



All I have left to do is the oversized tank, which will be here Monday, and one final ride and I'll be blowing it apart.
« Last Edit: January 05, 2018, 02:47:21 PM by umberto »
Perhaps I have a dirt bike addiction?

03 KX 250/88 KX 525/2017 KX250F - Goliath
17 KX250F/04 KX250
04 KX 250 - Lunchbox's Bike
05 KX 125/144

Offline zz3gmc

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Re: 2003 KX 250 SF Conversion
« Reply #217 on: February 05, 2016, 11:44:12 AM »
Looking good! Im in the middle of a long awaited rebuild of mine!

Offline umberto

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Re: 2003 KX 250 SF Conversion
« Reply #218 on: February 05, 2016, 11:53:24 AM »
Post some pics, or it didn't happen.  :-D
Perhaps I have a dirt bike addiction?

03 KX 250/88 KX 525/2017 KX250F - Goliath
17 KX250F/04 KX250
04 KX 250 - Lunchbox's Bike
05 KX 125/144

Offline zz3gmc

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Re: 2003 KX 250 SF Conversion
« Reply #219 on: February 05, 2016, 03:59:50 PM »
If I get a chance, I dont usually take pics of a rebuild. I'll definitely take some finished product pics. Cyl is out getting replated and the exhaust bridges welded up. Going to send the head to Larry for the decomp mod. May experiment with lowered suspension maybe a half inch. Freshen up linkage bearings. Paint and graphics etc. Been riding the wheels off of it since it was built in 11! I have a 24hr race in NY coming up in july and I really want to race it there. I raced my 07 250 there last year.

Offline alexander-vmann

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Re: 2003 KX 250 SF Conversion
« Reply #220 on: February 06, 2016, 08:24:06 AM »
i have race tech spring on mine, cant say anything bad about it
KX 500 newbie

my bike: 1993 kx500

Offline umberto

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Re: 2003 KX 250 SF Conversion
« Reply #221 on: February 06, 2016, 09:11:54 AM »
I ended up replacing both ends with Race Tech springs.  It really stands up now when I sit on it, instead of sagging down.  I fired it up today, and it sounds like the jetting is pretty close to perfect now.  I may try to sneak out to my cousin's place and rip it around for a few minutes in the morning.  I can't be gone too long, the Super Bowl is on tomorrow evening.   :-D
Perhaps I have a dirt bike addiction?

03 KX 250/88 KX 525/2017 KX250F - Goliath
17 KX250F/04 KX250
04 KX 250 - Lunchbox's Bike
05 KX 125/144

Offline zz3gmc

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Re: 2003 KX 250 SF Conversion
« Reply #222 on: February 06, 2016, 12:13:44 PM »
Thats on tomorrow? Shows you how much I know about football! I'll be out riding!

Offline umberto

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Re: 2003 KX 250 SF Conversion
« Reply #223 on: February 06, 2016, 12:15:55 PM »
Sadly, I don't care who wins. I just watch for the commercials and attend for the food. Food coma, here I come!
Perhaps I have a dirt bike addiction?

03 KX 250/88 KX 525/2017 KX250F - Goliath
17 KX250F/04 KX250
04 KX 250 - Lunchbox's Bike
05 KX 125/144

Offline umberto

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Re: 2003 KX 250 SF Conversion
« Reply #224 on: February 09, 2016, 01:46:59 AM »
I took Goliath out on Sunday, and was able to sort a few things out.  The carburetor's power jet was insanely rich from the factory.  I initially thought that one half turn would make a difference, and we ended up turning it three turns, with probably two more to go to get it right.  It was hard to get to the screw, so we got it headed in the right direction and decided to put the last two turns in after I got home.  It's jetted very well with the needle, but it was nearly all the way out (rich) on the power jet.  Thankfully it doesn't involve buying any parts, just small hands to get to the screw.

The suspension was much better, although I might still have the front forks redone.  There is a bit of harshness that I couldn't adjust out with the clickers.  The shock felt good as is, so I'll probably leave it alone.  Once I blow the bike apart for powder coating I'll probably send the forks to Race Tech for some love.  Of course that involves me not riding the bike, which is really hard because it is a blast to ride. 

I got my IMS 3 gallon tank in yesterday.  The folks at Just Gas Tanks were very nice and got me the tank faster than the originally estimated.  IMS made a black version of the tank for me, which is semi-custom (but did not cost more) and takes a bit longer.  I didn't want to go with clear because it yellows over time.  I'll need to do some adjusting (like with the stock tank), but I think it will look very nice when installed.  Goliath's fuel consumption is not as bad as I originally thought, but having that extra gallon is nice insurance.

I post some pics with the tank fitted, and maybe one more ride report, and then it's time to bite the bullet and make her look pretty.
Perhaps I have a dirt bike addiction?

03 KX 250/88 KX 525/2017 KX250F - Goliath
17 KX250F/04 KX250
04 KX 250 - Lunchbox's Bike
05 KX 125/144