Vintage Dirt Bike Q & A

Found a 73 cr250 in a barn last week and started the restoration this week. After much effort we got the head and cyl off as well as both engine side covers. This engine looks new inside. Stock piston, stock bore (ring stuck). The engine # is 1009711.

My engine builder (who has built numerous Cr250 engines and is a successful vintage racer in his own right) pointed out the writing in the edge of the right flywheel. The following is handwritten on the fly wheel "304~3495". He has never seen such and I can't find anyone who has either. Seems to have been written with some kind of engraving pen.

Any help you could give would be greatly appreciated. As stated we can't find any evidence that anyone has been inside the motor. I believe it to be a low hour bike since it still has Bridgestone Motocross-7 tires (with 1973 date codes) and the factory Honda grips!

If anyone has any ideas about the # please let me know thanks.

Very early CR's had billet cranks,but I don't know when the cut off was,I wonder if it's one of them.

I think I remember seeing some hand engraved numbers on my 73 Billet crank. They are not that uncommon but very cool none the less. Another aspect of the early cr's that shows how much of the bike was hand made.