2005 yamaha yz250 questions

[05yz250]

Hi, I am new to the forums and just bought a 2005 yamaha yz250. The last bike I owned was a 1991 honda cr125 so I guess that is not a good comparison,but from my experiance my 05yz250 straight up rips.

Has anyone paced or clocked this bike on top speed?

I ride woods and open trails and was wondering if there was a step smaller rear sprocket I could use that would not greatly affect accleleration or low end?

I read that someone else also said that it feels like you have to short shift this bike when in the power band it revs so quick. I have the same feelings, it seems to me that the bike will max out its top speed really quick which is a good thing. But I would maybe consider 5 or 10 more top mph with a different tooth sproket or sprokets.

Any suggestions

 

[elf]

How fast do you want to go? My 00 toped out at about 75mph. We ran it next to a car on the road to see how fast it would go.

 

[05yz250]

75 mph is pretty good for me now that I have thought about it.

Since I just got the bike I will not mess with the sprockets until they wear out and need to be replaced.

What are some small mods to do for a little extra hp.

Air filter, pipe and silencer should make a difference with some re-jetting and maybe reeds. My bike also came with 4 other jets and a small pin a little over an inch long and I dont know what it is.

I also noticed some oil on the rear fender from the silencer. What is a good way to get oil off the plastics?

 

[Chris_S]

Forget the engine mods, the bike rips stock. You'll get more speed (aside from in a straight line) by ditching the crappy OEM tires and getting the suspension redone. I had my front revalved/resprung, the rear resprung, and mounted Dunlop 756's, and it's like night and day. It hasn't been an easy adjustment from thumpers, but it's a dream bike now and I couldn't be happier.

 

[elf]

carb cleaner and a rag gets the oil off. I think the metal pin is to hold your power valve acuator arm in place so you can loosen the bolt that holds it on. As far a hp do a search on 03 and 04 yz 250s , anything that worked on them will work on your bike since the engine has not been changed since the 02 model.

 

[05yz250]

Yeah, the bike pretty much rips in stock form, I will most likely just pipe it and put a high flow filter on it and re-jet if it needs it.

As for using carb cleaner to remove exuast oil from the plastic, have you done this and will it fade or strip the plasic of its shine?

I also have exuast oil on my white front shock covers from riding behind my brothers banshee. It will not come off with just water and a rag and shows up bigtime on white.

 

[sodflyer]

Carb cleaner or a little soap and water get's mine off easy. Just toped mine out last weekend at 74-75 or just around there.... that's plenty fast for me on the dirt I am using the trail tech computer for my speedo. I have a 04 yz250 with Vforce 3 reeds and a ProCircuit pipe.... even though you don't think you might need it those mods makes some good power down low for this bike. Jeff.

 

[05yz250]

Cool, I got the oil off with soap and water.

Yep I am definatly going to get a pipe silence air filterr and some reeds.

Will I have to rej-et with those mods?
And will those mods make me loose any top mid or bottom end?

 

[motoxpress]

The only real reason to pipe the bike is to move the power curve around. I had an 03 YZ 250 and had the Pro Circuit Platinum and the power was much more firmly planted in the mid range.

I HIGHLY recommend you get the suspension tuned. That made the biggest difference in speed for me - whether track or trail.

mx