Odd Sound

[ThomasJ]

Another odd sound for you oilhead guru's....2001 1150GS with 19k, run Mobil 1 15W50 in the box.

 

When it happens:

When the ambient temp is over 90F, engine well warmed up, under considerable load...specifically...going up a long hill at about 65 then immediately throttling open to the stop, either in 5th or 6th gear. No apparent loss of power.

 

What it sounds like:

Loud (even with earplugs in) random "clicking"...not pinging. When I noticed it first it sounded like the keys were rattling against something plastic but they weren't (aren't). Maybe not related is a rattle just a smidge above idle but only when very hot.

 

Any thoughts?

Thanks,

Tom

[Boffin]

I have always described pinging as the sound of marbles rattling in a tin. The best way to hear pinging it to get the engine hot, place it under high load - say a long hill in top at lowish revs - 65 should do it on a R1150RT - then whack the throttle wide open.

 

The way to avoid pinging is to keep the revs higher under load - say change down to 5th - and to feed more throttle in as you accelerate - the way Rossi does. Much kinder to the engine, uses less fuel and combined with the downshift, much, much faster acceleration. Consider going down two gears to 4th at 65.

[ThomasJ]

Thanks Andy...

 

The only time I was sure I heard pinging is in a car, under like conditions, with low octane fuel, and it sounded like a ping so that's my only reference.

 

I'll give your suggestion a go.

Thanks,

Tom

[RT Pilot]

What you have is most certainly "pinging", although in our oilheads I always thought it sounded like "clicking" noises too. If you're not running the highest octane you can get in the summer, I advise you to do so. In cooler weather you can get away with mid-grade fuel. Our older oilheads DO NOT have knock sensors, so we have to depend on our senses to compensate for it.

 

Like Andy says, just keep the revs higher in hot weather when under a load and everything will be fine. Avoid pinging--it can really damage your engine if it happens frequently.