Wanting a little more distance than was supplied with the standard WR250F tank in Australia, which is the standard YZ250F tank, I started looking around for options.
You can mount a WR400 Tank, but you also need to goto a WR400 seat, and overall, the seating position is quite different from the standard position.
The standard position is so good that I didnt want to change it.
A quite search, and a couple of posts to http://www.thumpertalk.com/, and the Clarke Tank was recommended.
I checked it out on the internet http://www.clarkemfg.com/home.html and found the exact model http://www.clarkemfg.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=CM&Product_Code=1388&Category_Code=yamaha, decided it was what I wanted, and proceeded to buy it.
I ended up getting it from Ballards http://www.ballards.cc/, and they sent it overnight. I've had excellent service from Ballards for every order I've placed there.
Fitting the tank was quite easy. Firstly, you remove the seat, radiator shrouds and original tank. Next you need to remove the various mounting brackets from the standard tank, and bolt them into the Clarke tank. I had no troubles doing this, all threads were exactly right, and straightforward.
When it came to putting the Clarke on, there was a little hassle with the wiring loom under the frame, it just needed to be pushed under a little more than it had been with the standard tank.
After mounting the tank, and putting all the other bits back on, it all fitted very well.
Before - Standard Tank
After - With Clarke Tank
Newer Pictures
The Clarke tank bends the front of the seat up slightly more than standard, you can sort of tell by the photo's.
However, after the first long ride, when it bedded in a bit, I noticed that the tank was rubbing on the top of the rear shock absorber reservoir. This is fairly simple to fix by placing some rubber spacing or similar on top of the already existing padding just near the seat at the rear of the tank.
Apart from that glitch, the tank has been flawless, in fact its better than standard when filling/on a ride, as you can see where the petrol is up to easier in it than the standard tank.
If you have an American WR250F, or a WR400/426, then this may still be relevant if you want to put a YZ style seat/tank combo on to the bike to get the better seating position of the YZ
The SDG seat is often used with the standard YZ or Clarke tanks with good results.