Author Topic: 2003 KX 250 SF Conversion  (Read 170081 times)

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Offline umberto

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Re: 2003 KX 250 SF Conversion
« Reply #30 on: June 03, 2015, 06:49:14 AM »
I took my first welding class last night, and I learned a lot in just the first class.  We actually got to weld quite a bit last night (enough to give me a welder's tan on my arm).  The instructor told us we could work on personal projects if we wanted to, so I am going to take my bike with me to class Thursday night.  I'll post some pictures of the progress. 

I'm not sure how much the welder I use would have charged me to put the motor mounts on, but the class only cost me $130, and they provide, steel, tools, welders, helmet, and all the safety gear.  Plus the instructor will be looking over my shoulder to make sure I have the welder set up correctly and I'm not messing up too badly.
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 justreal

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Re: 2003 KX 250 SF Conversion
« Reply #31 on: June 03, 2015, 07:50:50 AM »
 Wow that sounds like a pretty good deal ,a bit of an education and all the access plus a "tan" to boot for a buck thirty .

Offline umberto

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Re: 2003 KX 250 SF Conversion
« Reply #32 on: June 05, 2015, 02:40:18 PM »
I got a little bit more done on the bike today. I wasn't able to take it to welding class because I got home from work too late, but I was able to get the MX 31s mounted on the Tusk Impact wheels. Tusk doesn't make a wheel for the 2003, but the 2004 and up will fit if you use the stock brake side spacer on one side, and another brake side spacer (I bought a Tusk set) on the other side. (edit 1/5/2016: The two spacers will need to be adjusted a bit to fit.  I started out on the brake side and adjusted it down until the rotor was centered in the brake caliper.  I then adjusted the other side so the wheel fit.  I ended up at around 33.5 mm for the brake side and 32.5 mm for the other side) The stock 2003 brake rotor won't fit the 2004 and up wheel, but I was planning to upgrade to a larger one anyway. I also mounted the kickstand and the KDX intake. I will be taking it to the class on Tuesday. I'll post some pics of anything I get done.

« Last Edit: January 05, 2018, 02:29:21 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 umberto

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Re: 2003 KX 250 SF Conversion
« Reply #33 on: June 09, 2015, 03:46:18 PM »
I took the bike to class tonight, and got the front motor mounts fabbed and welded on. I used a similar setup to the factory mounts, with one on each side of the frame. My welding instructor made a pass over my welds to make sure they were strong enough. I'll definitely do some cleanup on them this weekend.

Here are the mounts before welding:




After welding:




Next class I'll be working on the head stay. I'll post more photos after class.
« Last Edit: January 05, 2018, 02:29:55 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 #34 on: June 10, 2015, 03:34:39 PM »
Lookin Good!

Offline umberto

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Re: 2003 KX 250 SF Conversion
« Reply #35 on: June 10, 2015, 03:58:45 PM »
Thank you!  Your advice has really helped me with the build.  I'm getting excited to ride it for sure.
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 #36 on: June 11, 2015, 04:10:46 AM »
Got my pipe mounted last night. I used the optional pipe mount for the 03 KX 250, which has a bolt hole and a stud. I just had to bend the pipe mount a bit to make it fit.



I also solved my clearance issue with the oil filler. Tusk makes this little dude for $9.99.

« Last Edit: January 05, 2018, 02:30:27 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 #37 on: June 11, 2015, 09:10:47 AM »
I think you will love it! It handles so much better in the modern frame!

Offline umberto

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Re: 2003 KX 250 SF Conversion
« Reply #38 on: June 13, 2015, 03:16:19 PM »
I made some progress on the bike today, although it doesn't really look like it. I got the throttle and cable installed, replaced the busted front brake line, got the new rotor installed  and finalized the front wheel spacers, got the hydraulic clutch set up (more on that later), replaced the head gasket, replaced the chain adjusters that were frozen, and got the pipe bent around the coolant pipe.  




The hyrdaulic clutch is giving me some issues.  I don't think it has enough travel, which is not fully disengaging the clutch. I was able to roll it in gear, which initially made me think I had a compression issue.  I installed the kickstarter, and the motor felt good.  I'm going to install a standard clutch lever tomorrow and see if it is the Magura system or the clutch itself.

I'm also not really satisfied with the pipe either.  I had to really bend a couple of sections to get around the coolant pipe and to allow me to take the pipe off. I'm thinking about buying another pipe and doing some splicing to give me more clearance around the restrictions. I have access to an expert welder in my welding class, who happens to be a fellow dirt biker. Might as well take advantage of it.  :-D
« Last Edit: January 05, 2018, 02:30:46 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 #39 on: June 13, 2015, 03:19:18 PM »
Whole bike view:

« Last Edit: January 05, 2018, 02:31:07 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 #40 on: June 26, 2015, 09:28:53 AM »
I got a lot of work done since my last post.  I ended up buying another CR pipe and doing some splicing to make the pipe fit better without denting it too much.  I added an inch to the section that goes towards the ignition side, and then a pie shaped piece (about one inch at the top, and about 1/4 at the bottom) to bring the pipe around the coolant transfer pipe on the cylinder head.  All in all I am pleased with the pipe.  I also found a nice used FMF Q silencer and got that mounted as well.  The previous owner had cut off the lower silencer mount, so I improvised a bit with a triangle mount.  If it is not strong enough, I may have to have the lower mount repaired.  I also got the radiators mounted and the hoses ran.  I had to grind the weld down on the frame for clearance, and weld over and drill and re-tap the mounting holes on the bottom.  The new location required redoing the radiator braces.  I made them out of some material at welding class, but I may redo them in aluminum this weekend.  I am now down to the wiring, airbox, and details.  Hopefully I can post a ride video this weekend.  I realized I never bought plastics for the bike, so it will be a bit hooptyfied.  No redneck jokes.   :-D





New lower pipe mount:
« Last Edit: January 05, 2018, 02:31:46 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 Foxx4Beaver

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Re: 2003 KX 250 SF Conversion
« Reply #41 on: June 26, 2015, 09:53:39 AM »
No redneck jokes.   :-D



that silencer should say "Louisville Slugger" on it! :-D

just kiddin, I love the long "Q" silencer look on the conversions.
« Last Edit: January 05, 2018, 02:32:11 PM by umberto »
Excuse me, ma'am...but you've got extremely nice legs!!!...what time do they open???                                                                                                               https://www.youtube.com/watch?v=n8tCgN3aryQ

Offline umberto

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Re: 2003 KX 250 SF Conversion
« Reply #42 on: June 26, 2015, 11:24:54 AM »
No redneck jokes.   :-D



that silencer should say "Louisville Slugger" on it! :-D

just kiddin, I love the long "Q" silencer look on the conversions.
That's so funny, I was laughing about how huge it is while I was making the mounts today.  It makes the other models looks like toys.  I am trying to put as much silencer on it as I can.  I think the neighbors are ready to shoot me for all the motorcycle noise that comes from my driveway on a daily basis.   :evil:
« Last Edit: January 05, 2018, 02:32:26 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 Foxx4Beaver

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Re: 2003 KX 250 SF Conversion
« Reply #43 on: June 26, 2015, 02:01:19 PM »
a Louisville Slugger decal would look awesome on it. :mrgreen:
Excuse me, ma'am...but you've got extremely nice legs!!!...what time do they open???                                                                                                               https://www.youtube.com/watch?v=n8tCgN3aryQ

Offline motopunk

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Re: 2003 KX 250 SF Conversion
« Reply #44 on: June 26, 2015, 02:28:16 PM »
No redneck jokes.   :-D



that silencer should say "Louisville Slugger" on it! :-D

just kiddin, I love the long "Q" silencer look on the conversions.
That's so funny, I was laughing about how huge it is while I was making the mounts today.  It makes the other models looks like toys.  I am trying to put as much silencer on it as I can.  I think the neighbors are ready to shoot me for all the motorcycle noise that comes from my driveway on a daily basis.   :evil:

the bike will come out great, when it is finished ... very good work umberto ...
« Last Edit: January 05, 2018, 02:32:42 PM by umberto »
big 2 stroke bikes are weapons for real men, who don´t fear death or devil. ;O)
´83 kx250, ´87 kx250 (with 360 big bore), 87 kx500, ´93 kx500 sfc

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