03 WR 250F - With Ice Cube 315 Kit - Need advice for friend

[MCKLX300]

Let me first start by saying that you Guys are quite passionate about your WRF's & YZF's, the ThumperFAQ is quite impressive. It answered most of my questions, however I still have a couple.

Ok, I feel somewhat responsible for recommending this to him, as he really wanted a YZF and I talked him into a 03 WR 250F RPM 315 and BTW he is coming off a YZ 426F and rides 50% trails & 50% moto to give you an idea of what he is used to. BTW, after riding this weekend with another riding compadre' with a 05 YZF 315, I think he made the right decision with the E-Start WRF. ? He said he loved the Ebutton, especially after seeing our other friend kick away his 05 YZF 315 several times after getting a few "soil samples".

Although there is plenty of power in with WRF, he wants more, so I had suggested perhaps a YZF flywheel with a Z-Start might be the hot ticket. So my question is, what is the YZF flywheel weight vs the WRF ??? The next question is the Cams, are the intakes the same ??? I know the exhaust Cams are different, so would you recommend the YZF cams, or the Hot Cams.

Many Thanks in Advance

Michael C

Rocklin, CA

02 KTM 520 EX/C

97 KLX 331 - Spare

[BigIvyI]

Swapping to a yzf flywheel will involve changing the stator and pick-up as well. Then you will need the yzf CDI box to go with. I spent some time trying to swap wr stuff to a yz once when my yz ignition went south. It doesn't match.

If he want's more power, cams, exhaust, jetting, aftermarket ignition and power-now would be good options.

[Soul Man]

I'm not sure if this is correct, but I think the YZ flywheel wouldn't be compatible with the WR charging system that you need for that lovely E-start (since you have to change the stator).

[MCKLX300]

I guess It does not appear to be anything that anyone with a WRF has ventured into from a flywheel standpoint, so I am making the educated guess that most Folks are very happy with the additional WRF flywheel weight vs the YZF flywheel weight.

Any insight on the Cams ??? Do have to change the intake cams, on the WRF, IE, do you set one tooth off, or is the same indentical intake cam timing as the YZF ?

Anyone have any experience on the WRF to YZF exhaust Cam, vs the Hot Cams vs Exhaust Cam ??? When I use the search engine in brings up "anything" and everything with the word "cam", so it is very hard to mine through all the threads.

Many Thanks in Advance for any information.

Happy Trails !!!

Michael C

Rocklin, CA

[ThumpItGood]

Well. I can tell you that stock YZF cams going to Hot Cams both intake and exhaust made a nice difference. Better midrange. Power is all there. Theres definately a torque differance.