Just got a fresh out the crate 2013 RMZ250! Should be a nice upgrade from the 2004 RM125

 

Also guys for trail riding in Michigan (Baldwin trails) what's the cheapest way of getting a spark Arrester on my stock pipe so I can trail ride?

 

Not as much as you think. The 125 two strokes race against the 250 four strokes and the 250 two strokes race against the 450 four strokes.
I what them race every weekend during the summer.

Two strokes make much more power per cc than a four stroke thats why there allowed to have the larger displacement advantage to keep things fair.

They have people who care and look at your muffler/Pipe where you ride?

 

They are DNR trails! I have rode there many times and never had my pipe checked but they do Require you have a spark Arrester and I don't want to buy a aftermarket pipe. I have seen some Inserts you can buy but none for the stock pipe.

 

Got to ride the new 2013 rmz250 a little today and got to say I don't know really how much more Performance if any I feel from this bike Compared to my 2004 RM125!! Definitely The engine characteristics are different from 2 to 4 stroke but I am not at the Moment convinced I will run faster with this bike Compared to my old rm125. Don't get me wrong the RMZ is sick and is going to be loads of fun to trail ride with but I think it's Important for me to give my 2 cents hear in case someone thinks the are upgrading when they go from a 125 2 Stroke to a RMZ250. I won't know anymore than this till I get it out on the trails I use to ride but what do you all think about what I just said?

 

The 2 stroke and 4 stroke have a different characteristic, the 2 stroke powerband hits quick and hard in the mid and high rpms,the 4 stroke will have more of a smoother roll on powerband across a wider board.
Its really a taste preference rather than any advantage between the two.

 

2 strokes have to be kept in their power band, which is narrow.
The 4 strokes have a much wider powerband (lugs harder).

 

With the 4 stroke,s 125cc advantage over the 2 stroke it better lug harder.

Could you imagine the discontinued RM250 two stroke racing the new RM250 four stroke without a displacement advantage? It would be a massacre.

 

The theory they use is it takes twice the cc's with a 4 stroke to compare.
Altho, with the new 4 strokes, this theory is waaaaaaay off.
example: When I dyno'd my 250R it had 32hp at the rear wheels. The guy said that number was average.
They are pumping out 60+ hp on the 450's now.
The RM vs the RZ could be alot closer at the checkers that we may think.

 

They sure detune the 450s in the ATVs. The Honda TRX450R is 45hp range while there CR450 is 55hp. 2012 Honda CRF 450 R Specifications - Mbike.com

I remember my old CR250 2 stroker rated at 45hp. 1999 Honda CR250 Specifications | eHow.com