2003 250 for off road use-info needed

highmileage

Member
Jun 17, 2004
168
0
Well, some twist of fate and found a 2003 YZ250 in pristine condition (ridden once and obviosly so) for a bargain price.

I will be setting it up to ride tight woods and more open GP's. I completed a search and I am pretty confident in my plan, but have a few questions. Main goal is to have very smooth/broad/hitless power delivery.

FMF pipe and sparky; which combo (leaning Fatty/TCII Q)

9oz or 11 oz flywheel weight (leaning 11 oz)

stock gearing is 14/50 thinking of 13-14/48, thoughts?

single taper needle like DDK or CCK?
 

Chris_S

Member
Nov 25, 2002
143
0
I have an 11oz. and like it a lot.

I'm very happy w/ the stock gearing...it gets me through all the tight stuff I need, yet has enough top end for my needs.

I have no exp. w/ FMF exhausts, but I have a PC Plat. II and long silencer, along w/ a V Force3, and it rips!
 

Studboy

Thinks he can ride
Dec 2, 2001
1,818
0
I love my 02 YZ250 for offroad.

I usually go to a 13/49 for really tight stuff, but leave the 14/49 for more open trails.
I bolt up the 11 oz flywheel weight and turn the clickers out on the suspension a bit. Raising the forks in the clamps also helps.

I've found the stock pipe to be the best offroad pipe for me. I haven't had the need to change the needle, but having the proper jetting all around is important for smooth low end response.
 

Lorin

LIFETIME SPONSOR
Jun 25, 1999
948
0
I have an 03 with the FMF Fatty, and it is a little abrupt. It has great power (especially for mx), but is a little bit of a handful in the tight stuff. I have ridden back to back with a pro circuit pipe, and the pc pipe seems to have a smoother transition. Made the bike almost electric. I also put in a delta reed (from my 98) and an 11 oz flywheel weight. I havent seen the need to change the gearing at all. The only thing I have considered changing is to a pc pipe. I am running a spark arrestor as well, which is considerably quieter than the fmf silencer.
 

highmileage

Member
Jun 17, 2004
168
0
Lorin, Are you stating that the Platinum or Platinum II is the way to go with the silencer? Are you using the woods friendly or 296?

The other thought was a v-force III, worth it?

Once summer break comes I will send it to EG and get Mo Better porting to accentuate the positive. I want more electric than most.
 

2-Strokes 4-ever

~SPONSOR~
Feb 9, 2005
1,842
4
Missouri
The Yamaha has a really good woods motor. Hawk, (GNCC guy) says he prefers the FMF gnarly. (Although it didn't seem all that "magic" on my RM). I run a FMF Q, good power and I feel it is an important sound issue these days. V Force is good stuff, more power, crisper response, friendlier delivery. Leave your reed spacer in for smoother hit. More head-pipe length will make the motor "gruntier" too, (add 2-3 washers to exhaust port before pipe goes in). Or, does the Yamaha design let you do that? Don't know for sure. Have buddies that go from 6-12oz flywheel weights, just depends on your terrain. I think gearing is a terrain thing too, here in tight, rocky Missouri, adding 1-2 teeth to rear is usually the standard, for a "B" caliper rider, on an MX-converted bike. Enjoy!
 

Orangeman64

Member
Jan 14, 2005
31
0
woods yz creation

Hey guys, I just started riding a 2000 yz 250 a couple months ago, mainly riding woods, but play a little on the tracks(I'm 40 so the jumping thing can be a little intimidating with all this new power). I just put a 9 oz fly wheel weight on, a FMF gnarly and a power core II exhaust. I also added a skid plate, frame guards, and almost most importantly for the woods a good set of barkbusters(only took 1 tree to make me buy those). I hope to get out this weekend and try out the fly wheel weight and new exhaust system. Will then have to decide if rejetting needed, fmf sends a sheet on what they recomend as far as the jets with the new set up specific to your bike.
 
Cookies are required to use this site. You must accept them to continue using the site. Learn more…