Hi, I am 5'9" and 140lbs and looking for a new bike. I have been riding a 125 4stroke and it is way to small and lacks power. I dont know if I should
1) Buy a yz125
2) Buy a yz250f
3) Go big and buy a yz250
I have to pay for it with my own money and also want to put aftermarket parts on it. I will be trail riding, but there is a slim chance I will race (if i get enough money i might!!) I definitely want a yamaha. What should I do?

*** Only read this if you meant to say you have been riding a 125 2 stroke***
If you have been ridng a 125 4 stroke. I say YES you DEF have outgrown the bike, and I would still get a 125


I hate to say it, but the 250F will not have more power than the 125.
The 250F has its power more widely spreadout through the powerband
With your size & weight, a 125(liquid cooled) bike is not too small for you. Maybe if you were reaching 200lbs then yes It might be

The 250F, 125 and 250 2T will all have a very similiar seat heights. You just need to learn how to properly keep the 125 in the "hot spot". If you are having troubles with keeping it pinned, then sure a 250F or 250 2T will be much easier. But it will also make you a lazier rider. I would personally stick with the 125, it will make you work harder for faster lap times

Please dont take this negatively. Im not trying to bash you im just giving my opinion. Take this coming from a guy that sold his 02 YZ125 and purchased a 05 YZ250F

Sense your buying it yourself, i'd say a 125 would be the best bet

There are mods that you could do to make the 125 a trail monster but stock, they're not so good

And if you got the 250F, and you ended up blowing the engine, its big bucks for a repair

Hope this helped

thanks, i didnt think i needed a 250 2stroke, but i was just makin sure. my buddies both wanted the 125 and a was leaning towards the 250f, but now ill have to rethink that

I have an 06 YZ125 that has a very even powerband. With the new ignition mapping on the newer bikes, they really make them easy to use. You do not have to be on the pipe all day long like the older bikes. They have also brought back a 125 only class in a lot of ameteur races.

I would get an 06 or newer YZ125. A lot less maintenance and worry with a 125. If you need to rebuild, it is easy to do yourself and cost is low. I weigh 190 and still feel the bike has plenty of power for me. All of the guys I ride with always want to take it for a ride and they are always grinning when they bring it back. For trails, you may want to add a flywheel weight.

I would not worry about mods right away, go use the bike stock first. Since 06, the magazines say this is the best 125 made. I paid $3600 for mine brand new, although you don't find many deals like that anymore and I bought mine in January.

I hope this helps. You will have a ball on your 125 and it will make you a better rider like the others have stated.

well theres a couple of things that you need to consider.
1) will it be easy to find a 125 now that a lot of companies stopped making them
2) do i want a two or a four stroke
3) can i handle the power of a 250
4) how easy will it be to find after market parts
after thinking over these things just look at each bike and its reviews, sometimes you think that you have the right bike but after reading you find out that they aren't so great.
I think that you might want to stick with a 125 2t or a 250 4t, but thats just my opinion.

You said in your original post that you'd race when you can afford it. That suggests your not made of money... so you may want to leave the 250f out of the question. It will cost a lot more than the 125 or 250 2t stroke to keep running.

The 125 would be great IMHO, however the 250 2t isn't such a bad choice either, they can be very tame, its up to you whether or not you ride it sensibly or not. The 250 will be easier to ride in the end if you have good throttle control because you can lug it down low and not stall or be short of power, as with the 125 you will be changing gears more often and be revving it out a lot more.

Hope i have helped

i ride i 125 4 stroke 2 and i am moving up and i am a similiar size to you and i went and rode  08 crf 250 and i loveeed it. it didnt feel like to big of a bike for me and it was easy to get used to. if you are going to trail ride and 125 might be a little much for you depending on the difficulty of the trails. but the 125 would be cheaper to maintain and the cost of the bike will be cheaper.
i hope this helps

The 125 is going to be better for you.

What all would I need to do to make the 125 trail ready? I know I would have to put on a flywheel weight and probably some handguards, but what else?

MotoMan40 said:

I would say a Bigger Gas tank and More comfortable seat. Stock yamaha seats are horrible for long distance trail riding

MotoMan40 said:

You shuold deff get a new exhaust system. I suggest FMF sst pipe to broaden the powerband and the turbinecore 2 silencer to make u U.S. forest leagal. Not quite sure if u can combine the two because i think the SST only works with certain silencers but u can find out if u call FMF customer service or any other suppliers customer service. You should also look into Barkbusters.

MotoMan40 said:

FWW and handgaurds like you said, FMF gnarly pipe, spark arrestor,a skid plate, and different gearing and you got yourself a trail beast

dude get the 250f .a yz250 will be to much for you right now a 125 will lack power on tight trails 250f is defintaly the way to go you would hate a 125 for a wile befor you get used to it and you would still like a yz250f alot more on trails....by the way i have a 06 yz250f if that helps :-)

the YZF would probably be the best. 125 get crushed out here so I don't know about that, if you want to make them a weapon, it will cost you. The YZF will be much better stock, and rarely rarely rarely blow up.

2005+ YZ125. Stock pipe is great actually. Gnarlies aren't made for 125s. Skid plate, radiator guards, and possibly a Rekluse auto clutch. That'd be a nice woods bike. Go ride one to be sure. Again, the '05+ model is a new tech 125 compared to the old hat light switch 125s.

What about a 98 RM125? I found one on craigslist for $1000, which leaves me with $1000 for parts.

look around for a 02-03 yz250f, you should be able to find one for around 1500. and all it will need is hand guards.

MotoMan40 said:

you only have 2k? thats a whole different story lol. I was going to say get the 06+250f but nevermind. Now you should get a 05 125 or like 02-03 yzf. The 4t will do much better on tight trails. you never explained what kind of riding you do so...

test ride both and see what one you like best