Vintage Dirt Bike Q & A

The chrome plating on my 78 cr250 cylinder is starting to come off.

This cylinder has a bridged exhaust port, I thought someone in the past told me that the 79's had a bridged exhaust port and the 78's didn't, is this accurate?

Here are the engine numbers:

CR250ORE
1005432

Are there any differences between a 78 and 79 cylinder?

What are my options for repairing this, and what is you experience with it.

Thanks for any advise on this.

Another option would be to have a new liner pressed in. Then you would have over bores available.

79 cylinder has a bridge in the intake port for longer piston life . Send it out and get it plated . Don't go the sleeve route as the sleeve is a huge heat sink . We do a nice 2mm overbore with porting to match if you need a little extra grunt .

my cylinders are nicasil replated, much better than chrome plating or iron liners.

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