Vintage Dirt Bike Q & A

I recently bought a magazine off ebay that had a detailed article of the Honda MR250. The article was great except at the end under the bike specifications the horsepower and torque listing said NA. Does anyone have an article that has an actual horsepower rating?? I just want a factual number. Please do not give me a guess.

Thanks

I've seen three written numbers - 22, 24 and 25.

The question is - back then were those numbers at the crankshaft? If so they are definately a bit high comparred to the rear wheel numbers which suffer quite a bit due to clutch/transmission/chain friction losses.

Mike

Sorry about that man - I see you posted "MR" numbers. I replied with the numbers I've seen listed for the MT250...

My apology on that one it's late ie: 3:16 in the morning (man that's an erie number maybe time for a prayer! LOL).

Mike

Would you say the MR would have more power than the MT? From just comparing the cylinders, the MR has much larger porting which I feel would give it more power.

The MR250 motor would probably have more power than the MT250 for one reason it had a 34mm carb versus the MT250 having a 28mm carb. The MT250 was based on the 73-74 CR250 motor with a smaller intake port on the cylinder and the 28mm keihin. The MR250 was based on the 75-76 CR250 having the same intake port size and same carb. I have both bikes. The MT250 with a stock pipe is a bit slower than the MR250. Both are hampered by the heavy flywheel and restrictors in the pipes. A MR250 cylinder could be made the same as a CR250 by raising the exhaust port height a little. Removing the huge silencer from the MR250 will boost power easily. Other performance mods are not so easy.