Strange sound. Like crinkling

[Ubertino]

When I go WOT, around 5.5k (I don't really know, I'm generally looking at the road) I get a brief one-two crinkling noise, like a small piece of metal or something in the right jug area is, well, crinkling. Sort of like a opening-candy-in-the-movie-theater type sound. I'm not sure if this is throttle body related, valve related or what. Only does it when it's at higher revs at WOT. I don't like things making noises that I don't understand on my motorcycle. Another way to put it would be like wadding up aluminum foil, but real briefly and twice. I usually back off the throttle at this point since I'm not comfortable with the noise.

Help!

[MCMXCIVRS]

Sounds like detonation, AKA: pinging. There could be any number of possible causes, but basically detonation is caused by the fuel burning too quickly in the cylinder. Its usually due to very lean conditions. It can also occur if the sparks is too far advanced, but that will usually be much more prominent than what you describe. The condition can be exagerated by either fuel with too low an octane rating (higher octane fuels will burn more slowly and controlled) or by increased compression (either from carbon build up or mechanical changes).

A similar but less common condition is preignition, which is when the fuel is actually ignited prior to the spark firing by a hot spot(s) in the cylinder (usually a carbon deposit).

So, what to do. Check your fuel - perhaps try a higher rating, check your injectors for improper spray pattern, check for carbon build up, check the ignition timing.

[Ubertino]

Thanks!

So, I only use 92 or 93 octane right now, so I doubt it'll be that.

I just adjusted the valves, but the problem is the same both before and after.

I can pick up some techron to try and do something with the carbon, or seafoam. Which one is better?

So, then how does one check injectors for spray, and how does one check ignition timing? I don't think this is like doing the timing with a light on my chevy.

My plugs are a bit carbon'd up. I'll replace those too, perhaps they'll help. And I still need a tbs...

[PUDGYPAINTGUY]

Techron is my favourite personally. As for the timing you may be better to get a Haynes manual or Clymer as it will offer pics and description that this forum setting may not offer effectively for a task so important.

Do a synch before you mess with the timing as it is hard to judge the performance without the tune being good.

Also what model is it, year, mileage etc?

[Ubertino]

It is a 1995 R1100R with 48,300 miles (roughly). I just did the valves yesterday, and am hoping to meet up with a local owner to get the throttle bodies sync'd.

I also notice sometimes what sounds like a metal chirp noise. This bike is driving me crazy- I keep on hearing things, even though it runs. Albiet with some buzzing at the higher rpm's, but I think that's just the beemer buzz.