Vintage Dirt Bike Q & A

I just bought a cr250m1 gp cylinder to put in my mt250 I still need a head. Anyway just wanted to know what the differnce between the two bikes was as I also wanted to put on the mossburger reed valves and they are for 73-74. Bikebandit shows the 73-76 bikes all use the same cylinder so as far as I know they are the same. Anyway I need help as I know nothing about these bikes and what was interchangable.

The 75-76 cylinders are not the same as the 73-74. The 75-76 had an up pipe which the exhaust port is on the left hand side of the bike when sitting on it.

The 73-74 exited out through the right side. I'm not sure how the porting has chaged through 73-77 if any. For a good look at a restored 1975 CR250 go to Vintage Factory.com and check it out!

Good luck.
frohrs1

75/76 have a crude "boost port " or 5th port in rear of cylinder above intake.

The cylinder hold down stud spacing is very different to 73/74 so cylinders are not interchangeable.

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'84 Honda CR500
'84 CR125
'85 KX125
'83 IT490
'82 Maico 490
'80 YZ465
'75 Husky CR360 GP Mikkola
'75 CR250
'72 DT2MX
'91 XR200

So then I have to use the 73-74 cr250 cylinder on my mt250 its a 75 does that matter?

it does not matter what year MT it is.the mt motor along with the 73-74 cr250 motors,the cylinder and head will bolt on.dont forget to get a pipe,carb to compliment the CR top end.

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(2) 1968 DT1 1970 RT1M,1970 DT1C 1971 RT1B Enduro 1974 MT250 1974 DT250A (2) 1975 DT400B 1974 DT100,1978 DT175
1975 CR250M1 1979 CR250R 1979 Kawasaki KZ400H1 Jesus is Lord!!