I am thinking about building a racer but am not sure which one to get. Which one jumps the best, lands, corners, and goes through whoops the best? Also which one is the easiest to handle and is the least tiring. Dont tell me about the engines because they are both weak and I am going to put a dirt bike engine with some b@llz in it. I just want to know which will be the best all around for racing MX. Thanks.

 

You will not find a 250R frame very easily, however, you will be able to buy a Laeger frame for like 1500 to 2000. I am sure others make frames too, but they are pricey. They are chromoly as opposed to steel, so there is an advantage there for strength and weight. However, the 400ex frame from Honda goes for about $600, so it is cheaper and much easier to get a hold of if need be since they are mass produced. It is your decision, I have never ridden the 250R, but I love my 400ex. They are very similar in design. Out of the box, the 400 has more suspension travel and aftermarket companies make everything for both.

 

If you are goin to build a racer, your best bet is a Lonestar chassis, but dont think there is any way to do it inexpensively. Frame alone goes for 2600 bucks. Why don't you get a used 250r Honda and have CT Racing build the engine into a power valved roost rocket. That thing makes over 50 hp.

 

well......what do the pros use? 250r!!!!!!!!!!!!!!!

 

Get a used 250R and have the motor modded. Don't put a dirt bike motor in, most don't have counter balancers and will shake you off your seat. 250R's frame geometry are about as good as it gets for MX.

88 TRX270R
00 400EX

 

I think taht either one would be a good chassis to use.
The pros are mostly using 250r frames because thats all there were for 10 years and it would be hard to change from somehing you have ridden that long to something new.
You can buy a used 250r frame for the same as a new 400ex frame, or a new Lonestar or Laegars chassis for a 250r for 2grand.
If it was up to me, I would buy a 250r frame (used) becaues they are supposedly stronger than that of the 400.

 

Both are awesome chassis to start with. I have to say buy a used 400EX and sell the motor if you want to transplant it. Every new part from Honda is cheaper for a 400 ex than a 250r. I would reccomend a Roll design +3+1 front end with custom axis shocks to get almost 15" of front wheel travel. The East Coast ATV race team has a pair of them with YZ400F engines and they look like they fly. Or you could get a 480cc kit for the 400ex engine. Or you cuold use a 250r chassis and get a trinity, FTZ, LRD, or ct 400cc engine kit, they all make over 55hp. If you really want a rocket, buy a 400EX chassis and a used 88-90 LT500R engine and rebuild the top and bottom end and put that in there. That should really fly. The YZ400F engine is the only dirt bike engine that I'd reccomend