I was looking for spare parts to repair my XT660R after the chain broke yesterday, and as I was looking on the parts manual I quickly glanced the diagram for the airbox:



And I couldn't help but notice "11", my bike doesn't have or has had it since new!

And that explains why last Thursday, as I was setting up my bike for the failed coast to coast run, I found dust inside the airbox. It was very fine dust, hadn't noticed anything unusual before, but lately I've been doing more off road riding, including sections of "fesh-fesh" (a type of fine dust resembling flour), and that is exactly what I found inside the airbox...

I did notice the dust had come in through the airbox cover, now I know why

And on Saturday the bike took in about half liter of oil after 800kms...

You know these bikes are notoriously hard to check the oil level. I had found that if I let it idle for 5 minutes on the centerstand I'd get a somewhat accurate reading, rev the engine a few times and it would read low, let it idle again for 5 minutes and it would return close to the normal level. Lately, it wouldn't, and I had added oil several times... Just a little bit each time I checked it.

Saturday it took oil even after idling for a minute, oil level wasn't coming up...

After getting it back to my parents place (where I keep my bikes) on the towtruck of shame (broken chain) I rode my XT660X home, and it definitely felt more powerfull than the XT660R...


This isn't a "sand" ingestion case, just very, VERY, thin dust. It has the consistency of... flour or talcum powder. It got into the airbox through the gap in between the airbox and the cover, which is a very tigh fit (even without the gasket )

I guess I'm looking at least to replacing the rings, probably the cylinder will have to be recoated...

Do you think the valves and guides could have been damaged?

What else should I look for?