Engine Knock

Continued tuning problems, a bit of knocking at higher temps and running hot according to my new crankcase gauge have been worrying me, so I had the guy from SF Motorsports take a look at it this morning. I had been riding it hard for 30 mins to get it nice and hot before I got there, then he rode it down the Interstate and came back, then ran the temps with an infrared gun. The front jug was 250f the rear 260f, apparently thats great and well within specs. Also the crankcase temp he was showing was much cooler than what my thermometer was showing, he says the gauge could be off or the oil is just that much hotter than the metal, but nothing to worry about. The gauge was reading 95C at the time.

I’m pretty sure the gauge is spot on, holding it in my hand for a while when it came in it was reading whatever 96F is.

On the knocking noise he says it does have a tiny bit of a knock but with as many miles is on my bike most of the ones they work on are much worse than mine. He says it feels nice and tight and surprisingly good still. I told him it started after my long ride against that massive headwind where I burned off all that oil and he says the 650’s will do that if you keep them at full throttle for a long time, it gets too hot and starts to wear down the bearings on the rods. He says just expect the knocks to get noisier over time, but nothing to worry about. He says they see these bikes last to 50K with not even taking care of them or doing hardly any maintenance, and it looks like I’m taking good care of mine so it should last a lot longer than that.

That other noise that I was thinking sounded like an exhaust leak maybe, was actually the intakes, it just sounds crazy loud with the windshield on there.

So all of this has been a huge load off my mind, I’ve been doing all this stuff chasing my tail for nothing I guess. I didnt have any cash on me and he didnt charge me, I think I’ll go back tomorrow and give him a $20 for being a huge help.

1 comment to Engine Knock

  • Hi mate … about the oil,hmnn yeah that is very common with mineral oils… High Temps and…… oil almost boil, then vapors spread out of engine… take a look at bunch of wires that come off the generator (left side chrome cover)next to parking lever…if oiled, try a better oil.
    I use SILKOLENE 10W-50 for V-TWIN engines Full Tinthetic… great!

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