Vintage Dirt Bike Q & A

As I recall, there was a trick to disable the rev limiter on the 1980 CR250 to allow them to rev out like the 78/79's. It involved cutting the green wire coming out of the source coil. Can anyone verify this or give me the proper way to do it?

I remember reading something the same "back in the day". Here's something to think on, though. The 1980 engine was changed to have more of a mid-range over the 1978 and 1979 engines. You may find that even though the engine can rev further, it's actually falling off and this will be counter-productive. What you can do is put a handlebar switch into the green wire circuit and see whether a) the engine will run with the wire broken and b) if yes, what effect it has out on the track.

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

if you have a wiring diagram you can see that the green cable is the electric ground.
when you cut it the ignition doesn´t work or the electrical ions go thru the other green cable to the ground.

2t engines are often rev limited by the design of the exaust pipe.

_________________
80 CR250Ra
80 CR250Ra
78 CR250R
80 CR80
82 Bultaco Sherpa 340
78 Bultaco Pursang 250 MK12
76 Bultaco Frontera 370 MK10
76 Bultaco Alpina 250
73 Bultaco Lobito 125 MK6
76 Suzuki RM125A
90 Kawasaki KX250

I found the article on modifying the ignitions. Sept 1980 Dirt bike mag. Mr Know it all,and I quote: "Some competitors have used the electronics for earlier model CRs. Also a trick on the earlier model 250s was disconnecting the rev limiter wire under the tank. It was green in color. All that needed to be done was simply to disconnect it from the electronics."
He should know, after all he was" Mr Know it all".