Thoughts on 2007 KX250 smoker

I believe front forks are the biggest things that need help. Valving or replacing with some newer ones

My cousin had one and it handled very bad. Buy it, it's got to be cheap and if thats what you can afford just keep it running clean and get your ass to the race track. See you on the weekend bro!

I have a 2006 KX250. Active Ride shortened the shock with an internal spacer, and built 2010 KX450F forks that have similar valving in them to a YZ250 - they will bolt up with a small shim in the top clamp, and running them slightly higher as the upper fork tubes are slightly longer.

My favorite handling bike that I have ever ridden.

I had a 2005(same bike). Engine was stout, handling lacked. Was better with suspension work, but not great. I still loved the bike. If its priced right, pick it up. I sold mine and regret it. She was a beauty.

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You can swap the whole front end off a modern KX250f or KX450f (Triple clamps, forks, Brakes, etc) but you'll need to purchase this steering stop adapter from Trick Engineering (45$ for Aluminum, 75$ for Ti, +10$ for Ti fasteners):

jbrass715 wrote:

I believe front forks are the biggest things that need help. Valving or replacing with some newer ones

The frame is the biggest thing that needs help... you can raise or lower the forks and sag to decide if it will push or knife, but I never rode one that just turned without any drama. I'd buy some really top of the line knee braces, because you'll be dabbing your foot everywhere.

The motor in those KXs is pretty impressive though

I’ve got an ‘06. Had FC do the suspension. I use it mostly in the woods with the occasional track day. I think the bike handles awesome, just play with the setup a bit. I think the ill handling of these bikes is blown out of proportion by the internet.

Engines are quite stout.

Longer (lower) link to help the back ends high stance. I have an 05 which doesn't have the same problem but putting it on my bike still helped. I also prefer an off-road pipe for more bottom end response. It has a strong hit but sometimes falls flat trying to get it there. Extra bottom helps lug it before cracking the throttle wide open. The bike rides better with a rear weighted riding style. It's very stable in high speed chop but likes to be steered with the rear, at least for me. I can't get the front end to bite to save my life and that may have something to do with the front forks. ¯\_(ツ)_/¯

*note - I do strip out shifters like crazy though. Steel, aluminum, billet, doesn't matter. After every weekend of riding I have to tighten the shifter and eventually it stretches out, there's no room left and the splines strip. Could just be the shaft teeth being worn out or riding style but I've never had this problem on any other bike.

Mine has been a solid bike. I've owned it for 7 years now and besides the occasional top end and replacing parts I break it's still going strong. It also takes parts from 03-18 for a lot of stuff. Most 4 stroke stuff, while maybe different, bolts right on.

Love my 05! More fun than a 450, but not as easy to ride.

Build link: https://www.vitalmx.com/forums/Moto-Related,20/2005-KX250-2-Stroke-Build,1301898

theycallmeebryan wrote:

You can swap the whole front end off a modern KX250f or KX450f (Triple clamps, forks, Brakes, etc) but you'll need to purchase this steering stop adapter from Trick Engineering (45$ for Aluminum, 75$ for Ti, +10$ for Ti fasteners):

Huge Thank You for the showing the steering stop adapter! I planned to take my 05 to the fabricator to get the Stop welded sometime this week....but not now. To the OP....Go for it, they're great bike's when set up properly.

BobPA wrote:

I’ve got an ‘06. Had FC do the suspension. I use it mostly in the woods with the occasional track day. I think the bike handles awesome, just play with the setup a bit. I think the ill handling of these bikes is blown out of proportion by the internet.

Engines are quite stout.

Yep.

The forks need a revalve.
Some lesser offset clamps will help handling.
Check the power valve spring.
The motor is midrange and up with a good hit. It's fun for the skilled pilot.
I have an 05 I bought new.

I had one, thought the steering was terrible, what MXA described on their test. Then I changed the triple clamps to applied 21.5mm offset, turned it into a great handled bike!

theycallmeebryan wrote:

You can swap the whole front end off a modern KX250f or KX450f (Triple clamps, forks, Brakes, etc) but you'll need to purchase this steering stop adapter from Trick Engineering (45$ for Aluminum, 75$ for Ti, +10$ for Ti fasteners):

ledger wrote:

Huge Thank You for the showing the steering stop adapter! I planned to take my 05 to the fabricator to get the Stop welded sometime this week....but not now. To the OP....Go for it, they're great bike's when set up properly.

Are the 250f forks longer? what about the offfset difference? How does it handle with new front end compared to original? I've got an 04 KX125, Not sure how for off a setup like this would be for it.

I love my 2006, I found it still in the crate about 5 years ago. For sure the stock suspension needs to be revalved, I use Race tech and have a good setting that I finally ended up with after a few tries. I run a PC exhaust however the stock pipe is very good! I also found a PC link and it has helped the turning a lot! Motor is very strong but will ping and has to do with the Air gap on the ignition pick up on the flywheel... do a search and you will find what I am talking about, that being said I have adjusted mine over and over and it still detonates under heavy load but I have never had a problem with it, it’s just annoying.

bvm111 wrote:

I love my 2006, I found it still in the crate about 5 years ago. For sure the stock suspension needs to be revalved, I use Race tech and have a good setting that I finally ended up with after a few tries. I run a PC exhaust however the stock pipe is very good! I also found a PC link and it has helped the turning a lot! Motor is very strong but will ping and has to do with the Air gap on the ignition pick up on the flywheel... do a search and you will find what I am talking about, that being said I have adjusted mine over and over and it still detonates under heavy load but I have never had a problem with it, it’s just annoying.

Bump your main jet up a bit. Mine would ping under heavy load too. I went one larger on the main and raised the needle up one position. No detonation all last year, and still runs crisp.

Lot good info for the 05-07 here. Isn't it funny how the magazines and internet label a bike as ill handling or a lame engine? If you find a good one for sale really cant go wrong.

bvm111 wrote:

I love my 2006, I found it still in the crate about 5 years ago. For sure the stock suspension needs to be revalved, I use Race tech and have a good setting that I finally ended up with after a few tries. I run a PC exhaust however the stock pipe is very good! I also found a PC link and it has helped the turning a lot! Motor is very strong but will ping and has to do with the Air gap on the ignition pick up on the flywheel... do a search and you will find what I am talking about, that being said I have adjusted mine over and over and it still detonates under heavy load but I have never had a problem with it, it’s just annoying.

Mine did the same, after i adjusted the air gap and used race gas it eliminated the noise

There was a dude ripping on one at Perris this weekend, he made that green turd look like a fun bike to ride. ?

bvm111 wrote:

I love my 2006, I found it still in the crate about 5 years ago. For sure the stock suspension needs to be revalved, I use Race tech and have a good setting that I finally ended up with after a few tries. I run a PC exhaust however the stock pipe is very good! I also found a PC link and it has helped the turning a lot! Motor is very strong but will ping and has to do with the Air gap on the ignition pick up on the flywheel... do a search and you will find what I am talking about, that being said I have adjusted mine over and over and it still detonates under heavy load but I have never had a problem with it, it’s just annoying.

MOTORSPORTFOX wrote:

Mine did the same, after i adjusted the air gap and used race gas it eliminated the noise

Same with my 05. Pump gas and it would ping like crazy!! C12 and she runs amazing. Never had the chassis issues that so many talk about. The only issue was the stock 05 forks SUCKED!!!!!! And that's probably putting it nicely. Otherwise, that bike is awesome!! She's never leaving our possession

bvm111 wrote:

I love my 2006, I found it still in the crate about 5 years ago. For sure the stock suspension needs to be revalved, I use Race tech and have a good setting that I finally ended up with after a few tries. I run a PC exhaust however the stock pipe is very good! I also found a PC link and it has helped the turning a lot! Motor is very strong but will ping and has to do with the Air gap on the ignition pick up on the flywheel... do a search and you will find what I am talking about, that being said I have adjusted mine over and over and it still detonates under heavy load but I have never had a problem with it, it’s just annoying.

MOTORSPORTFOX wrote:

Mine did the same, after i adjusted the air gap and used race gas it eliminated the noise

I am at the max on my air gap per the service manual, even tried the 07 spec but it became hard to start. I failed to mention that I have a TMR modified motor and run straight C12... it still does it. It isn't really a pinging sound it almost sounds like a sneeze for lack of a better term, usually third gear pinned on a jump face. Ive adjusted the jetting went richer on the main... lowered the clip, bought multiple different needles as recommended on thumper talk... still does it!

TJ 755 wrote: https://motocrossactionmag.com/reviving-one-of-the-worst-bikes-ever-testing-the-stomp-and-turn-2006-kx250/

Joko wrote:

I had one, thought the steering was terrible, what MXA described on their test. Then I changed the triple clamps to applied 21.5mm offset, turned it into a great handled bike!

Hey do you happen to have a part number for that Applied 21.5mm offset triple clamp?

Guys, there is some GREAT info on here for tge 05-07 bike...does any of this apply to the 2003 KX250? Ive scoured the internet trying to find any info or magazine test/review articles and cant find anything! 2 puff pieces that were from twmx and motorcycledaily.com....
My bike has an FMF Fatty pipe abd a v-force reed system, previously had a turbine core spark arrestor but i just replaced it with a stock oem silencer (freshly packed & cleaned out) and went from the stock 52 to a 48 pilot jet. Coupled with the silencer swap and holt crap!!! That bike runs like a scalded raped ape now!! Explosive off the bottom/mid almost hard to cintrol but fun to ride and it pulls into a decent top end that still flattens out a little still have the stock main jet until i redo the top end with the vertex piston kit i won on the pulpmx show this last monday night. Gonna need to do the 1mm spacer addition/powervalve mod to sort of smooth that transition out and i believe the engine will be golden.

Suspension is still stock and feels good but has this dead feeling at any good sized impact thats in the 3/4 part of the stroke the bike feels dead and kind of holds up in this part of the travel for a split second longer than ive ever experienced. Its a weird sensation bec my rebound settings feel like theyre in the ballpark for everything else. Does that make any sense??

Joko wrote:

I had one, thought the steering was terrible, what MXA described on their test. Then I changed the triple clamps to applied 21.5mm offset, turned it into a great handled bike!

queen of spodes wrote:

Hey do you happen to have a part number for that Applied 21.5mm offset triple clamp?

No, I had ordered them through ThumperTalk’s store, cost was about $430 after their discount. should be able to call Applied directly to order

I think the front brakes particularly could use some work, or at least they could on my 06, I assume the 07 is the same setup. I know the kx front brake bracket assembly will fit up to a 2009crf caliper on it ( I assume even newer also, just 09 is the newest I have). I have actually bolted it all onto the forks, but the calipers look the same dimensionally, and they use the same pads.

Joko wrote:

I had one, thought the steering was terrible, what MXA described on their test. Then I changed the triple clamps to applied 21.5mm offset, turned it into a great handled bike!

queen of spodes wrote:

Hey do you happen to have a part number for that Applied 21.5mm offset triple clamp?

http://appliedrace.com/shop/index.php?main_page=product_info&cPath=43_45&products_id=1440

TJ 755 wrote: https://motocrossactionmag.com/reviving-one-of-the-worst-bikes-ever-testing-the-stomp-and-turn-2006-kx250/

I posted that link on another thread not to long ago.

Test rode an 05 model (05-07 same chassis / engine) I think in 07 & couldn't get off the bike bike fast enough to give it back to the owner. One of the worst handling bikes I've ever ridden in 4 decades of riding MX. The engine had a narrow powerband if I recall with just a midrange hit. A CR or YZ in those yrs. is a much better platform to start with. The RM would be my 3rd choice.