I commute on my bike and ride it at weekends. I came to trade it in last week and the salesman nearly wet himself when I said it had 38,000 kilometer on the clock. It's two years old Kawaski ZX-6R fully registered (with green book). The sales guy said it wasn't worth that much and offered me next to nothing for it. So I'm hanging on to it for the moment.

What is the lifespan of a modern bike? Do major parts need replacing ever and what eventually "kills" bikes off?

We've asked a few people high up in motorcycle design teams and it's hard to get a straight answer. The team responsible for the Suzuki GSX-R750 would not commit to a number of kilometers or years their machine would run for. They just kept saying 'it depends on how the bike is used and serviced', which isn't totally unreasonable.

BMW on the other hand were happy to suggest their R1200GS would be good for 100,000 kilometer at the very least.

We've heard of plenty of motorcycles running twice that of what BMW suggest without needing new engines or major work. We're talking Japanese 600cc four strokes, while you can see BMW's with World War II stickers.

Inevitably, suspension, bearings, brakes, and clutches need to be replaced. Electrical problems seem to get increasingly common as motorcycles get older. Ultimately it's basic economics that send most machines to the dump yard. When a 460,000 Baht Kawasaki needs 300,000 Baht of work to keep it on the road for another year.

To answer, what is your Kawasaki ZX-6R worth? I belief you will get a good price, especially that your bike is fully registered, if you going to sell it privately by placing classified adds on several Thai websites. Success.