More Noobie ??? crackling noise from motor and...

[rpduc]

Sorry for all of the noobie questions, but I haven't had a dirt bike since 1975 so all this new-fangled 2 smoke tech has me a bit baffled. Never had reeds or powervalves before so...

I've now cleaned up and started all three of my GG steeds.

http://www.gasgasrider.org/forum/showthread.php?t=2295

On very short test rides on the only non snow covered real estate (the cul de sac ) I noticed an unnerving "crackling" sound emanating from the motors. I'm thinking it was just that it was maybe pinging due to loading the motor to heavily in too high a gear? I was running through all gears (in about 150 yards) just to make sure all six gears were there and was obviously not able to wind the thing up properly. I got this "crackling" when perhaps I lugged the motor? NOTE: I have been riding a 610 Husky "paintshaker" on the ice of late so my perception of revving is maybe a bit skewed.

Would I induce any foreign noises from either the power valve or reeds running it this way? They start, run, idle fine and lift the front wheel nicely but I am not familiar enough with the new 2 smokes to know what I should be hearing. Or might this crackling be a sign of something amiss in the PV or Reeds?

Do I need the plastic louvers on the radiators? Do they really do all that much? The 2 ECs have Flatland radiator guards and on one of them the louvers are cheezily slapped on there with zip ties. No louvers on the other one. The MC has the left louver that is sorta mounted correctly, but the plastic is tweaked so it hangs there kinda sloppy like. Right side is missing...

 

[gasIdaho]

Could be the chain slapping the chain guard on your swingarm. Common deal on GG's especially when you shift up and keep the rpm's low. Kind of a clacking noise. The first time I heard it I was like WTF?

Since I put on a TM Designs chain slide on the noise has gone away. The stock slide is a POS. Higher rpm's will make it go away too.

Louvers....not sure you really NEED them. They seem to keep the mud off my radiators pretty well.

 

[rpduc]

Could be the chain slapping the chain guard on your swingarm.

Thanks, I hope that's all it is. I'll have to investigate. I did find that the slightly bent and poorly mounted Flatland radiator guard on one of the bikes was slapping against the radiator at certain rpms causing a similarly unnerving noise.

I just look at all of those parts in the exploded view of the power valve and it makes me wonder. I unfortunately have no idea what kind of maintenance was done on these bikes, but judging from their overall condition, maintenance was not high on the previous owners agenda so everything is suspect ...

 

[GMP]

rpduc,

Good advice so far, the chain can slap the swingarm slider under certain load conditions(lugging) and make noise.

Powervalves are mechanisms with quite a bit of operating clearances, so they can function when fouled with spooge and carbon. This, with the pulse nature of the exhaust, causes a slight rattle at low RPM. Very noticable at or just off idle. If you have a skid plate, these sounds seem louder as they are reflected up toward you. Also, you could be hearing a secondary vibration, like the pipe buzzing against something, pipe springs, or worn pipe/spigot o-rings causing that joint to vibrate. Bad silencer packing will also give the bike a loud crack like tone.

The rads are eaisly damaged and should always have something in front. Rad guards are best. Louvers will do little but keep mud and small debris out of the fins.

 

[rpduc]

Powervalves are mechanisms with quite a bit of operating clearances, so they can function when fouled with spooge and carbon. This, with the pulse nature of the exhaust, causes a slight rattle at low RPM.

Thanks Glenn,
That's the kind of info I was looking for. I guess I won't know for sure what real bad sounds are on this thing until I incur some malfunction. I guess I need to get it to the dealer for a listen to get some reassurance that I do/don't have some catastrophic failure in the works.

 

[gasIdaho]

GMP. Any remedy for pipe spring vibrations?

 

[Loosenut]

Pipe spring vibratiuon can be reduced by sliding shrink wrap tubing over the springs. Sometimes, you just need new springs.