Vintage Dirt Bike Q & A

I've asked this question about 79-80 CR125s before, but will the lower ends from 78-80 CR250s interchange.

I mean can I mount a 78-79 cylinder on the 80 lower end?

Will the 80 CR250 lower end bolt into a 78-79 frame without mods?

Thanks!

J

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#829 The "Factory Novice"

1988 Honda CR250RJ
1983 Honda CR480
1981 Can-Am 250 MX6-B
1979 Honda CR250RZ
1979 Kawasaki KX250 A5
1978 Husky 250CR
1978 Honda CR250R
1977 Yamaha YZ400D
1977 Suzuki RM125B

I have a 79 cr250 bike thats complete and a 1980 cr250 motor and from what i have seen the lower ends are identical.I would if possible use the stator from the 79 motor on the 80 lower end,especially if its a E coded stator.

Thanks Dave!

I have an "E" ignition setup for my 78 CR250, but isn't the 1980 ignition better for Novice riders?

J

_________________
#829 The "Factory Novice"

1988 Honda CR250RJ
1983 Honda CR480
1981 Can-Am 250 MX6-B
1979 Honda CR250RZ
1979 Kawasaki KX250 A5
1978 Husky 250CR
1978 Honda CR250R
1977 Yamaha YZ400D
1977 Suzuki RM125B

I have heard something about the 80 model ignition doesnt allow the motor to rev out as far as a 78 or a 79 model will.supposedly the 80 has more low end and less top end than the 78 or 79 model.that might be in the porting as well though.I would guess a 80 model would be easier to ride than a 79 would though.I think PFR has a torque pipe dont they?

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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!!

The ignition is but one factor, but it is true that 1980 CR250RA owners seek out the 1979 CR250RZ "E" ignition for their motors. PFR does "rev" and "torque" pipes. As very much a novice I can say that the latter works just fine (on a 1979 motor).

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Michael Stiles
1979 Honda CR250R Elsinore | 2006 Husqvarna SM510R | 2007 Service Honda CR500R-AF

J,

All parts for the '78 to '80 CR250 bottom ends are pretty much interchangeable; however, there are several parts that were upgraded from year to year; the most noticeable would be the cases. The '78 cases lacked a shield behind the clutch lifter area (in front of the counter shaft) to protect the lifter recess when the chain gets tossed. Both the '78 and '79 left case halves lacked the three vertical support webbings at the area of the left transfers; which provide support to the base gasket area. And of course, everyone knows about the kick start pinion, clutch basket and ignition.

I'd think a really hot setup for the '80 CR250RA would be the "E" stator and CDI, the Pro-Form Mugen pipe and the Mugen ME250 Pro cylinder...I think that would be an interesting '80 bike to ride. I plan on trying the "E" setup on my '80 ME360, see if that will make it rev like my 125's.

Take care,
Robbie