2002 YZ250, Flywheel weight question

[jmutiger]

I'm a hare scramble racer, and an Enduro racer.. Expert class in Canada.. Anyways, I'm just about to pick up my 2002 YZ250,(new to me)..and I think I'll need a flywheel weight on it. A close friend of mine says this is one bike that just doesn't need it, but I'm sure if you add one it'll make a 3hr HS event that much less tiring.. Am I wrong?

Also, I'm getting the giant 3.9 Gallon tank from Clarke for it. Will that be enough to get me through a 2.5hr Hare Scramble without stopping? If I stop, I lose my focus.. That's why I went with the big tank (as opposed to the 3.1 gallon one). Our 2.5hr HS races usually end up being 3hrs by the time your done.. Can it be done on this amount of fuel?

Thanks,

Jon!

(Is the stock jetting good ??) (so many questions I know)

 

[Lissa]

Im posting under my girlfriends name. Anyway, I am a A level enduro rider in New Jersey. We have alot of tight woods and our series takes us to PA and NY into some pretty rocky and technical terrain. I ride an 02 YZ 250 also and did not add a flywheel wieght to it. I felt that it did not need one. I was able to easily lug it up some nasty, slippery trails without any problems. However, I just purchased a E -Line lighting coil for it and that will add about 10 oz of wieght to it. On my 01 YZ 250, which has a similar power delivery, I ran a 11 oz Steahly wieght that worked well. Rob

 

[Lissa]

Also, my 02 will go about 40 miles with a IMS 3 gallon tank under race conditions. I have stock jetting in mine. Im pretty much at sea level.

 

[jmutiger]

Thanks Rob/Lissa.

If you ever wanna come up here and try some of our Enduro's Hare Scrambles let me know. It'd be cool to show you some of our local trails the day before a race, or after a race.

Jon!

 

[Studboy]

Cool, so the concensus is: 02 YZ250, doesn't need a flywheel weight for most conditions, but as always it doesn't hurt? If you did go with a weight, how big would you go on the 02 YZ250?

 

[Rcannon]

Based on the experience I have had with my 1997, get at least 10 oz. I would get one. The feeling is similar to running a smaller countershaft sproket without any of the drawbacks.

I was afraid to put this one on my bike. I was afraid it would make it feel like one of the 1970's trail bikes.

I have had a lot of guys ride my bike. Most are better riders than I am. No one disliked the weight. In fact, most believed I had the bike proted.

 

[cornwalker]

2003 YZ250. I have the 9oz weight and it took my bike from a 2nd-3rd gear bike in the woods to a 3rd gear. I had problems lugging the bike in 3rd and stalling it. Has not happened even once since I got the flywheel weight. I also put on a 49t rear sprocket and a FMF gnarly pipe/shorty silencer. I used to ride a 2002 KTM 200. This bike will flat out smoke that one, hands down. AA rider

 

[yz1kurt]

The 2002 yz 250 comes with a weight on it. I ride mx and a little woods thought I would go to a 2001 unweighted flywheel because I like it to hit hard. I left the stock weighted flywheel on and love it . It hits hard and still hooks up really well.I would leave what Yamaha gave you alone unless where you ride is extremly steep and slick and in that case get a 4joke.

 

[jmutiger]

It comes STOCK with a flywheel weight?

That's odd..

Another question, can I add a lighting coil to the stator plate on this bike? (cheap and easy way to get some lights)

Jon!

 

[stevep]

My suggestion would be to fit steel clutch plates and go up one tooth on the front sprocket, that will give you more of a spread of workable power as well as mellowing out the engine slightly.

 

[Rcannon]

Steve, have you tried a weight? Seriously, I know what it sounds like . They sound like they will make your bike feel like a trail bike. They sound like the bike will rev slow and hit soft. On mine, not true.

The bike makes a ton of midrange power. It feels like more. The first day riding with it I darn near looped it twice on flat ground. I was just screwing around, but the engine hits hard! There is a lot less wheelspin.

Top end power feels the same. But, the midrange feels so much better that you rarely have to use the top end. Shifting is reduced about 50%.

The weight is way more noticable than the Piep, silencer, rad valve, and gearing changes that came before it. My only regret is not buying a weld on model. The bolt on idea bothers me. No problems, I just do not like the idea of bolting on.

 

[grunk250r]

I think all the YZ's come with steel clutch plates don't they??

 

[Lissa]

The 02 YZ 250 comes with steel plates. My 01 250, 00 125, 97 wr 250 all had steel plates. The 02 YZ has a heavier fly wheel than the 01. For me, I added a tooth to the rear to bring the power down lower in the power band. I would run a tooth bigger in the front only if I take it to a dualsport or somewhere I need more top end so as not to work the engine too much. I tend to ride in the midrange more and prefer instant responce.

 

[Lissa]

This is Rob not Lissa.