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Do "free mods/uncorking" still apply to 2007-2014 WR250F's?

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Considering buying a brand new WR250F runout, so will be a alloy frame. Have read lots of uncorking stories for the pre alloy frames - grey wire, open pipe, jetting to suit and you have a street legal YZ.

 

Is it the same with the newer style WR's? Am I even right in saying that uncorking the older bikes makes them like a YZ?

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Are you buying the US spec WR250F or Australia? From what I understand, your WRs of all years are not corked like the US models.

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Would be Aussie spec, I assume they are the same without the emissions gear?

So would still run a softer ignition map, corked up exhaust, ?

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I rode my wr250f for the first time today and honestly, I really hope it's still restricted. Even after the dealer told me they unrestricted it.

It feels slow....does a yz exhaust system and JD jet kit fix them?

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It starts to get moving in the top end, but it just takes for ever to get there.

I am coming off a yz 125 though....is this just how it is?

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The dealer maybe just did the yz throttle stop screw. There is a gytr kit for removing the emmisiins stuff but that sounds like it is mainly just weight removal. In order of mods I wiuld do. Check throttle stop, remove snorkle from air box, unplug grey wire and tape it up. Exhaust, I like Akrapovic, (ballards had a good deal a couple of years back) JD Jetting kit, or 09 YZ needle (you also need the needle jet as they are diferent sizes). All the "how to" can be found on here in old threads. Get this right and the bike will be a nice ride, enough so that you will find the front folks need some profesional attention. The next step is a yz/ hi comp piston and a set of cams.at that point you have a pretty grunty 250f. I just swapped mine for an fx. The FX gets off the mark and makes revs a whole lot quicker but the WR felt a lot gruntier when really bogged down, like when going up short steep banks you can give it a hand full of throttle, dump the clutch and it will hook up and then grunt to the top. I still have to work on my technic on the fx. Being lighter in the front end I need to get my weight furher forward, need to be better with the clutch as it revs earlier and quicker being more likely to wheel spin, also more likely to stall if you chop the thottle too early at the top. After 7 years on WR s -with them being so easy to ride, I am finding I need to be not so lazy in my riding style, showing a lack of fitness, but when I get it right on thr FX it is very rewarding.

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After riding the bike a little more - Its not really slow, its just "different" to what I am used too (YZ 125), I am moving alot quicker on it, and am alot more confident which is nice. I am just adapting to the new style of riding.

 

My bike didn't come with a snorkel in the airbox, havn't checked the grey wire. Will have to look up and find out where its located on the alloy frame bikes.

 

Is it worth getting a Jet kit even with the stock pipe? I kind of like the low noise. It seems also pretty touchy on cold start, I feel like I have to let it idle for ever with the choke on before i can get on and ride it. I also noticed a bog in low rpm when cracking open the throttle. Is this normal? Can it be fixed? Even when my 2 stroke was about to stall, I could wack the throttle open and it wouldn't bog and die, it would still try and pull through.

Edited by m0tyrider

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If your coming from a yz125, there are alot of differences you will need to adapt to before you start making changes.   And yes, I let my bike idle at the lowest rpm possible for around 1-3 minutes depending on temps outside.  I see people at tracks revving the 4 strokes to warm them up like a two stroke and I can't help but think this is so WRONG.    Although I'm no engineer, the oil needs to circulate before revving.   If your WR is already unrestricted a JD Jet kit or your own jetting will help as well as a Fuel screw to fine tune it, I didn't notice a huge difference with the gray wire.   The WR exhaust on the US model was Massively restrictive.   If it has a bog, there are different Leak jets you can try and several carb mods you will read about here, some expensive, so I would try leak jets first.   The us model comes with a 70 or 80 leak jet, which is apparently too large you can try a 50, which worked for one of my WR's, others have not needed it.

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Just sold my 07 WR250,  I had done all the free mods,  grey wire cut, desnorkled,  installed a GYT  end cap or exhaust outlet installed a JD jet kit,  blue needle worked best particularly for cooler temps.  I added a tooth to the CS sprocket as we run fireroads/ 2 tracks, some gravel and pavement and I hate to wring the engine out to hit those speeds.   Seldom in 1st gear even in tight 1tk.   It runs pretty good,  I installed a FMF snap a bit ago,  and definately helped the bottom end.  It's all but impossible to stall and lugs pretty good for a 250.  Oh yeah pulled the AIS off it too.  

The bike is a real sweet runner.  

 

 

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The grey wire is found behind the left hand side cover. Yes there would be benefit in using a jetting kit with the std muffler. After market mufflers don, t need to be unduly loud to make good power.

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Phew! because I just ordered a JD Jet kit - and was hoping to keep the muffler stock.

 

I have put a few more km's on my bike and now I am starting to get used to it. Its great!

 

Its just a different type of riding style compare to the 2t 125, very different. But feel much more relaxed, and I feel alot more confident on it.

 

Hope the jet kit fix's the bog and ill be one happy chap.

 

4 stroke exhaust systems seem pricey, I might be look at a used YZ system. That said I am sure it would be alot louder!

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