Rebuilding intervals crf250r

[greasyhonda]

Thinking about getting a used crf250r just wondering how many hours I should do before getting a top or bottom end rebuild I do mostly trail rides and the odd flat track and ride at about medium pace

[ktm84mxc]

Top end should last 100 hrs if trail ridden, valves should be checked/adjusted every 50 hrs, bottom end will see 200 hrs all being well.
Most important is regular oil and filter changes every 10 hrs for the engine, 20 hrs for the gear box as these are separate. Also the CRF's run a specific spark plug it's not cheap though it is a race plug.