2-Stroke Winter Project: YZ250 vs RM250

YZ for sure. RM's in decent shape are getting hard to find and guys want too much for them. Parts are getting hard to find and too expensive. Off road setups for the YZ are well figured out and easy to create. Example, wide ratio tranny from the newer 250X, etc.

FGR01 wrote:

YZ for sure. RM's in decent shape are getting hard to find and guys want too much for them. Parts are getting hard to find and too expensive. Off road setups for the YZ are well figured out and easy to create. Example, wide ratio tranny from the newer 250X, etc.

Yeah I'm leaning 90% toward the Yamaha, but thought I'd reach out and try to learn something more about the RM250 too.

There is a really clean 06 here local for $2200, which prompted more thought toward the Suzuki, but again you make a great point - parts for the YZ, especially geared for an off-road setup will be a lot easier to locate.

06 rm 250 is a great handling bike, motor is good, pv is a little adjustable, I had one with a flywheel weight, wasn't ideal in the woods but it worked, great on a mx track, much better than my yz kn the handling department. but the yz is my go to bike, parts are reasonably priced, motor is good and works excellent in the woods for mx bike. It's a hard call, I would be content with either

As an owner of both, go with the YZ for sure. You'll have a much easier time finding off-road specific parts and there is nothing that the RM is going to do much better than the YZ. Since you're in for a project anyways I would highly recommend the four stroke swing arm swap, just make sure you get one prior to the switch to the reverse YZF motors. Pay no attention to the MXA article on the matter, it's complete bullshit.

Yz for sure!

JM485 wrote:

As an owner of both, go with the YZ for sure. You'll have a much easier time finding off-road specific parts and there is nothing that the RM is going to do much better than the YZ. Since you're in for a project anyways I would highly recommend the four stroke swing arm swap, just make sure you get one prior to the switch to the reverse YZF motors. Pay no attention to the MXA article on the matter, it's complete bullshit.

What does the swingarm-swap do?

I've owned a 2004 RM250 (bought new), a 2006 YZ250 (bought new) then some 4-strokes, and now I have a 2007 YZ250 (used). I ride both MX and off-road.

RM250: The fit and finish is not as good as Yamaha but that doesn't mean the bike was unreliable. I never had any issues with it mechanically. But what bothered me were the shrouds. I'm tall and when I sit up on the seat, my knees are pretty far forward. The RM felt wider to me and the shrouds didn't have enough.....holes (for lack of better term) where I could sort of lock in with my knees. Whenever I gripped the bike with my knees, I felt like I was pushing myself backwards. Also, forks felt better on the track than on the trail.


06 YZ: All was well until I discovered a lot of play in the supposedly perfect SSS forks. At first I thought my steering stem was loose because I could move the fork lugs back and forth. Turned out to be the sliders wiggling around in the outer tubes. I replaced the bushings (old ones looked OK) but the problem was still there. Meanwhile some friends got thumpers and the grass looked greener so the YZ got sold.


07 YZ: Forks was the first thing I checked. They were fine. So far I'm stoked on the bike. The clutch pull is a little stiff but otherwise no complaints.


I think the YZ is hands down the winner. But not because it's such a better bike. It's just a more practical bike. Parts are easy to get. The aluminum frame doesn't age (in appearance) like steel. Bike is still in production. There's a wealth of information online on how to upgrade/fix them up. Here's some stuff I have done to my 07 or am in the process of doing...

* Stiffer spring off of YZ450 (cheap way to keep a Ti spring yet go up in spring rate)
* 2009 YZ450 triple clamps (four position clamps)
* 2010 YZ450 footpegs (not as light as Ti, but they are wider and sit lower)
* Zip-Ty racing oversized tank. Made by IMS to Zip-Ty's specs. Maintains low profile so the seat/tank junction isn't ridiculous
* the swingarm mod is something I'm planning to do. Already have the swingarm, but I still need the axle, wheel and caliper carrier. I like the idea of less unsprung mass.

All these mods are not available for the RM. Or at least not as cheaply. Most of this is just take-offs from newer thumpers. It's a no brainer in my mind.

I have a 2004 RM250 that I ride all the time and I have no issues finding parts. The bike seems to be pretty indestructible, They are solid bikes but I have ridden the YZ also and it is really good. Go with the best one of either that you find has the right combination of history, price and condition.

I’ve had both as well, I’d probably go YZ for a lot of the reasons stated. Parts availability alone is big. Both are great though. RM turns a little quicker, might be good for the woods. Steel frame is better as well in my opinion. I do like the YZ suspension better though.

I vote RM! I've got both and in my opinion the RM does everything better than the Yz. Most notably turn and feel like a feather! I will say the stock clutch sucks on an rm. it's just grabby.

mx_563 wrote:

I've owned a 2004 RM250 (bought new), a 2006 YZ250 (bought new) then some 4-strokes, and now I have a 2007 YZ250 (used). I ride both MX and off-road.

RM250: The fit and finish is not as good as Yamaha but that doesn't mean the bike was unreliable. I never had any issues with it mechanically. But what bothered me were the shrouds. I'm tall and when I sit up on the seat, my knees are pretty far forward. The RM felt wider to me and the shrouds didn't have enough.....holes (for lack of better term) where I could sort of lock in with my knees. Whenever I gripped the bike with my knees, I felt like I was pushing myself backwards. Also, forks felt better on the track than on the trail.


06 YZ: All was well until I discovered a lot of play in the supposedly perfect SSS forks. At first I thought my steering stem was loose because I could move the fork lugs back and forth. Turned out to be the sliders wiggling around in the outer tubes. I replaced the bushings (old ones looked OK) but the problem was still there. Meanwhile some friends got thumpers and the grass looked greener so the YZ got sold.


07 YZ: Forks was the first thing I checked. They were fine. So far I'm stoked on the bike. The clutch pull is a little stiff but otherwise no complaints.


I think the YZ is hands down the winner. But not because it's such a better bike. It's just a more practical bike. Parts are easy to get. The aluminum frame doesn't age (in appearance) like steel. Bike is still in production. There's a wealth of information online on how to upgrade/fix them up. Here's some stuff I have done to my 07 or am in the process of doing...

* Stiffer spring off of YZ450 (cheap way to keep a Ti spring yet go up in spring rate)
* 2009 YZ450 triple clamps (four position clamps)
* 2010 YZ450 footpegs (not as light as Ti, but they are wider and sit lower)
* Zip-Ty racing oversized tank. Made by IMS to Zip-Ty's specs. Maintains low profile so the seat/tank junction isn't ridiculous
* the swingarm mod is something I'm planning to do. Already have the swingarm, but I still need the axle, wheel and caliper carrier. I like the idea of less unsprung mass.

All these mods are not available for the RM. Or at least not as cheaply. Most of this is just take-offs from newer thumpers. It's a no brainer in my mind.

* 2009 YZ450 triple clamps (four position clamps)

Whats needed for the swap?

mx_563 wrote:

I've owned a 2004 RM250 (bought new), a 2006 YZ250 (bought new) then some 4-strokes, and now I have a 2007 YZ250 (used). I ride both MX and off-road.

RM250: The fit and finish is not as good as Yamaha but that doesn't mean the bike was unreliable. I never had any issues with it mechanically. But what bothered me were the shrouds. I'm tall and when I sit up on the seat, my knees are pretty far forward. The RM felt wider to me and the shrouds didn't have enough.....holes (for lack of better term) where I could sort of lock in with my knees. Whenever I gripped the bike with my knees, I felt like I was pushing myself backwards. Also, forks felt better on the track than on the trail.


06 YZ: All was well until I discovered a lot of play in the supposedly perfect SSS forks. At first I thought my steering stem was loose because I could move the fork lugs back and forth. Turned out to be the sliders wiggling around in the outer tubes. I replaced the bushings (old ones looked OK) but the problem was still there. Meanwhile some friends got thumpers and the grass looked greener so the YZ got sold.


07 YZ: Forks was the first thing I checked. They were fine. So far I'm stoked on the bike. The clutch pull is a little stiff but otherwise no complaints.


I think the YZ is hands down the winner. But not because it's such a better bike. It's just a more practical bike. Parts are easy to get. The aluminum frame doesn't age (in appearance) like steel. Bike is still in production. There's a wealth of information online on how to upgrade/fix them up. Here's some stuff I have done to my 07 or am in the process of doing...

* Stiffer spring off of YZ450 (cheap way to keep a Ti spring yet go up in spring rate)
* 2009 YZ450 triple clamps (four position clamps)
* 2010 YZ450 footpegs (not as light as Ti, but they are wider and sit lower)
* Zip-Ty racing oversized tank. Made by IMS to Zip-Ty's specs. Maintains low profile so the seat/tank junction isn't ridiculous
* the swingarm mod is something I'm planning to do. Already have the swingarm, but I still need the axle, wheel and caliper carrier. I like the idea of less unsprung mass.

All these mods are not available for the RM. Or at least not as cheaply. Most of this is just take-offs from newer thumpers. It's a no brainer in my mind.

Excellent info - I appreciate your time in typing all that out.

My takeaways: the Yamaha is definitely the better option given how I'll use it. I'm sure both would be fine.

I didn't even know about that Zip-Ty tank - thank you very much for mentioning it. That was one of my major issues with this bike or the RM - I hate the look of a big 3g tank but I know I'll need it for most riding and racing I'll do. But this version of the IMS looks pretty good; definitely better than the regular one.

Good idea on the OEM clamp swap too - I like my bars dead-even with the center point of the fork; if I can't get that with the clamps it comes with I'll do this.

I haven't dug into the swingarm swap and won't worry about it until I get knee-deep into this. Seems like a ton of work for a small payoff.

b8res wrote:



Love my 06 RM... I've raced both, the YZ is also a great choice!

Such a clean look. Love my 05 RM.

b8res wrote:



Love my 06 RM... I've raced both, the YZ is also a great choice!

That track with the building in the back looks familiar....

Id say YZ just because they still make it and getting any part big or small is a click away. Idk if RM parts are hard to come by, but I only rebuild or replace parts with OEM.

I own, (recently sold, and 07’ RM 250), an 17’ YZ 250’ and a couple of 07’ CR 250, along with a few other bikes. From a fit and finish stand point the rm lags way behind the yz and cr, I have had all 3 torn down to the frame. Parts are much harder to get, and are more expensive.
I had Factory connection do the suspension on both the rm and yz and they both felt similar, with maybe an edge In plushness to the yz. I had them setup for an a level hare scramble rider(me).
Handling wise, the rm would go whoever it was pointed no questions asked, but it was scary at high speed. The yz had a front end push that was really annoying in hard packed conditions, but it was stable I did like the yz in muddy conditions more than the rm. As far as which one was better overall, it really depends on what you are going to do.
From an astetics stand point, I really like the rm. I used Hyde frame guards and they really did a nice job of protecting the frame. I used a clarke oversized tank on it, but I hated it. On the YZ I used a Zip-Ty tank and IMO is the best oversized tank for the Yz.
Engine wise, both were similar, with the rm being a bit freer revving even when both had 13 oz fww. For off-road use I would give the nod to the Yz for it’s smoother power.
With all of the above mentioned, my favorite bike is the cr 250. It’s a combination of both the yz and rm suspension and handling wise , with an engine that is easily tuned to perform just as good as the yz or rm. The kicker is the durability that neither the yz or the rm can match. I already have the engine out of the 17’ yz, while I have yet to go into the bottom end of the cr. I had to replace the transmission in the rm before I could even ride it.

digger wrote:

I own, (recently sold, and 07’ RM 250), an 17’ YZ 250’ and a couple of 07’ CR 250, along with a few other bikes. From a fit and finish stand point the rm lags way behind the yz and cr, I have had all 3 torn down to the frame. Parts are much harder to get, and are more expensive.
I had Factory connection do the suspension on both the rm and yz and they both felt similar, with maybe an edge In plushness to the yz. I had them setup for an a level hare scramble rider(me).
Handling wise, the rm would go whoever it was pointed no questions asked, but it was scary at high speed. The yz had a front end push that was really annoying in hard packed conditions, but it was stable I did like the yz in muddy conditions more than the rm. As far as which one was better overall, it really depends on what you are going to do.
From an astetics stand point, I really like the rm. I used Hyde frame guards and they really did a nice job of protecting the frame. I used a clarke oversized tank on it, but I hated it. On the YZ I used a Zip-Ty tank and IMO is the best oversized tank for the Yz.
Engine wise, both were similar, with the rm being a bit freer revving even when both had 13 oz fww. For off-road use I would give the nod to the Yz for it’s smoother power.
With all of the above mentioned, my favorite bike is the cr 250. It’s a combination of both the yz and rm suspension and handling wise , with an engine that is easily tuned to perform just as good as the yz or rm. The kicker is the durability that neither the yz or the rm can match. I already have the engine out of the 17’ yz, while I have yet to go into the bottom end of the cr. I had to replace the transmission in the rm before I could even ride it.

I've somewhat thought of a Honda as well, but aren't they duds beyond 2001? What year is yours? I've rode a friend's 05 once quite a while ago and thought it was..bland.

My vote goes to the YZ. 100% based on part availability. Theyve had the same bike for so long with no changes, you have no risk of not finding parts. Millennium technologies has cylinders in stock so theres no turn around if you need a replate. Pistons are everywhere. Overall those are great bikes. I built a 2001 a couple years ago and had a great experience with every aspect of it.

Deetsmx wrote:

That track with the building in the back looks familiar....

Last year at DT-1.... Valley OTHG National.. fun track...

b8res wrote:



Love my 06 RM... I've raced both, the YZ is also a great choice!

Deetsmx wrote:

That track with the building in the back looks familiar....

b8res wrote:

Last year at DT-1.... Valley OTHG National.. fun track...

The good ole poop plant!! Haha! It may smell like crap there, but the dirt is awesome!

Deetsmx wrote:

That track with the building in the back looks familiar....

b8res wrote:

Last year at DT-1.... Valley OTHG National.. fun track...

mattyhamz2 wrote:

The good ole poop plant!! Haha! It may smell like crap there, but the dirt is awesome!

I always have a shitty day racing there........ yea.. that dirty can be really good when prep is on point!

digger wrote:

I own, (recently sold, and 07’ RM 250), an 17’ YZ 250’ and a couple of 07’ CR 250, along with a few other bikes. From a fit and finish stand point the rm lags way behind the yz and cr, I have had all 3 torn down to the frame. Parts are much harder to get, and are more expensive.
I had Factory connection do the suspension on both the rm and yz and they both felt similar, with maybe an edge In plushness to the yz. I had them setup for an a level hare scramble rider(me).
Handling wise, the rm would go whoever it was pointed no questions asked, but it was scary at high speed. The yz had a front end push that was really annoying in hard packed conditions, but it was stable I did like the yz in muddy conditions more than the rm. As far as which one was better overall, it really depends on what you are going to do.
From an astetics stand point, I really like the rm. I used Hyde frame guards and they really did a nice job of protecting the frame. I used a clarke oversized tank on it, but I hated it. On the YZ I used a Zip-Ty tank and IMO is the best oversized tank for the Yz.
Engine wise, both were similar, with the rm being a bit freer revving even when both had 13 oz fww. For off-road use I would give the nod to the Yz for it’s smoother power.
With all of the above mentioned, my favorite bike is the cr 250. It’s a combination of both the yz and rm suspension and handling wise , with an engine that is easily tuned to perform just as good as the yz or rm. The kicker is the durability that neither the yz or the rm can match. I already have the engine out of the 17’ yz, while I have yet to go into the bottom end of the cr. I had to replace the transmission in the rm before I could even ride it.

KGAspeed wrote:

I've somewhat thought of a Honda as well, but aren't they duds beyond 2001? What year is yours? I've rode a friend's 05 once quite a while ago and thought it was..bland.

You’re never going to get the RM or YZ to handle as well overall as the CR for as little as It takes to correct the CR’s engine. The 05-07 CR’s need the cylinder base cut .030 off the bottom and have the heads squish corrected. That’s about $120 worth of work. I also recommend using a Keihin PWK AS carb. I get them off of eBay. I usually have about $120 total into a correct working carb. With those mods it’s right on par with the yz and rm.

Owned a 2005 RM250 and still have a 2006 YZ250.

Both are great bikes but I'd go with the YZ for these reasons...

- RM250 clutch is weak compared to the YZ. Easier to make it sqwauck and heat it up and the release point is kind weird compared to the YZ

- YZ parts availability better.

- Prefer the YZ suspension.

I race Florida Trail Riders hare scramble and someone had a 92 YZ250 out there last weekend that was absolutely like new. This thing even had stock replica pink/fuscia (whatever that is) graphics. Truth be told I hated those bikes especially in that color back then but I so want one now.

Mx746 wrote:

* 2009 YZ450 triple clamps (four position clamps)

Whats needed for the swap?

That depends. If you are willing to live with the stock YZ250 offset (25mm) then just make sure you get clamps from a 2009 YZ250F or 2009 YZ450F....direct swap.

If you want the 22.5mm offset, then you need to get the 2010 or newer clamps (off of a 4-stroke).

HOWEVER: Starting in 2010, the top clamp fork tube holes were 54mm (whereas 2-strokes are 56mm). So in order for a 2010+ thumper clamp to work with a 2-stroke, you would need to machine the clamps to open them up to 56mm. Otherwise you would need the thumper forks too (and possibly a front axle, etc....not sure).

I was not comfortable doing this. I don't want to do anything (such as material removal) that could weaken my clamps. So I opted for the 2009 setup with 25mm offset. I'm 220lb and coming off of a 4-stroke, the YZ feels like it turns just fine. I can live with 25mm offset.

More info here: https://thumpertalk.com/forums/topic/1152402-yz250-triple-clamps/

KGAspeed wrote:

Excellent info - I appreciate your time in typing all that out.

My takeaways: the Yamaha is definitely the better option given how I'll use it. I'm sure both would be fine.

I didn't even know about that Zip-Ty tank - thank you very much for mentioning it. That was one of my major issues with this bike or the RM - I hate the look of a big 3g tank but I know I'll need it for most riding and racing I'll do. But this version of the IMS looks pretty good; definitely better than the regular one.

Good idea on the OEM clamp swap too - I like my bars dead-even with the center point of the fork; if I can't get that with the clamps it comes with I'll do this.

I haven't dug into the swingarm swap and won't worry about it until I get knee-deep into this. Seems like a ton of work for a small payoff.

I confess, the swingarm swap is a little over the top. But since I bought the bike used, I gave myself permission to go a little nuts.

I realize that the steel frames are more compliant. But finding a clean steel frame YZ isn't easy anymore. Most of them are roached out. Plus, according to MXA (I know, I know...) when Yamaha went to the aluminum frame on the YZ, they shaved 7.5 lbs off the bike. That's nothing to sneeze at. They did some stuff in subsequent years to further drop the weight. Considering how light the KTMs are, I want every edge I can get.
https://motocrossactionmag.com/we-test-the-2005-yamaha-yz250/

Here's a pic of a Zip-Ty tank...


More pics with tank... https://dirtbiketest.com/product-tests/zipty-racing-ims-3-2-gallon-tank-yz-125250/#efKRwcH2yH6YUiMt.97

And if you like trick tanks and have unlimited financial resources...there's this...

http://www.xfun.it/en/product/271/Aluminium-Fuel-Tank-for-Yamaha.html

or this: (vlarr racing - Netherlands)

https://www.vitalmx.com/community/pete24,30229/setup,35940

mx_563 wrote:

I've owned a 2004 RM250 (bought new), a 2006 YZ250 (bought new) then some 4-strokes, and now I have a 2007 YZ250 (used). I ride both MX and off-road.

RM250: The fit and finish is not as good as Yamaha but that doesn't mean the bike was unreliable. I never had any issues with it mechanically. But what bothered me were the shrouds. I'm tall and when I sit up on the seat, my knees are pretty far forward. The RM felt wider to me and the shrouds didn't have enough.....holes (for lack of better term) where I could sort of lock in with my knees. Whenever I gripped the bike with my knees, I felt like I was pushing myself backwards. Also, forks felt better on the track than on the trail.


06 YZ: All was well until I discovered a lot of play in the supposedly perfect SSS forks. At first I thought my steering stem was loose because I could move the fork lugs back and forth. Turned out to be the sliders wiggling around in the outer tubes. I replaced the bushings (old ones looked OK) but the problem was still there. Meanwhile some friends got thumpers and the grass looked greener so the YZ got sold.


07 YZ: Forks was the first thing I checked. They were fine. So far I'm stoked on the bike. The clutch pull is a little stiff but otherwise no complaints.


I think the YZ is hands down the winner. But not because it's such a better bike. It's just a more practical bike. Parts are easy to get. The aluminum frame doesn't age (in appearance) like steel. Bike is still in production. There's a wealth of information online on how to upgrade/fix them up. Here's some stuff I have done to my 07 or am in the process of doing...

* Stiffer spring off of YZ450 (cheap way to keep a Ti spring yet go up in spring rate)
* 2009 YZ450 triple clamps (four position clamps)
* 2010 YZ450 footpegs (not as light as Ti, but they are wider and sit lower)
* Zip-Ty racing oversized tank. Made by IMS to Zip-Ty's specs. Maintains low profile so the seat/tank junction isn't ridiculous
* the swingarm mod is something I'm planning to do. Already have the swingarm, but I still need the axle, wheel and caliper carrier. I like the idea of less unsprung mass.

All these mods are not available for the RM. Or at least not as cheaply. Most of this is just take-offs from newer thumpers. It's a no brainer in my mind.

Mx746 wrote:

* 2009 YZ450 triple clamps (four position clamps)

Whats needed for the swap?

mx_563 wrote:

That depends. If you are willing to live with the stock YZ250 offset (25mm) then just make sure you get clamps from a 2009 YZ250F or 2009 YZ450F....direct swap.

If you want the 22.5mm offset, then you need to get the 2010 or newer clamps (off of a 4-stroke).

HOWEVER: Starting in 2010, the top clamp fork tube holes were 54mm (whereas 2-strokes are 56mm). So in order for a 2010+ thumper clamp to work with a 2-stroke, you would need to machine the clamps to open them up to 56mm. Otherwise you would need the thumper forks too (and possibly a front axle, etc....not sure).

I was not comfortable doing this. I don't want to do anything (such as material removal) that could weaken my clamps. So I opted for the 2009 setup with 25mm offset. I'm 220lb and coming off of a 4-stroke, the YZ feels like it turns just fine. I can live with 25mm offset.

More info here: https://thumpertalk.com/forums/topic/1152402-yz250-triple-clamps/

I agree that stock offset is fine. These bikes are really good. Here’s a before an after of mine.

I say YZ250 mainly because I currently have a yz250 project I'm working on as well.