grey wire reconnect

[starfish]

Hey anybody ever reconnect the grey wire? My bike was jetted etc.., before i took delivery from the dealer. Does it make it easier to ride in slippery conditions? Figure a on/off switch could be handy. Try to make my bike easier to ride in tight slippery single track.

[jams229]

I did the switch mod you talk about. I like having the option of switching to "WR mode" in the real technical or snotty conditions. I would say I leave it in "YZ mode" most of the time, but there are times it's nice to have the WR power. You have to turn the motor off prior to switching between modes.

I tell all the KTM guys it's like having a KTM whenever I want one and then with the flip of a switch, I've got a YZ...

[mvryder]

I read something on the mapping of the grey wire. I really think it is something that is only intended to be used with the throttle stop. It might be hard on the bike running it in that second half of the throttle range with the wrong mapping. I also put a lot of stock into the fact that the Yamaha instructions tell you to unplug the wire when you change the throttle stop.

[William1]

I have a switch on my WR. I leave it in the YZ setting all the time though last weekend, I should of at least tried the WR position to see if it would of made life easier in that slop!

The YZ setting is a more advanced ignition curve.

The WR mapping is actually easier on the engine as the engine produces less power. Yamaha tells you what to do to completely wake your sleeping WR.

[mvryder]

The reason it produces less power is because it retards the timing. I think it is just harder on the engine. It is basically slamming the crank at a less than optimal time. I think it is actually harder on the crank shaft and crank shaft bearings. There is is same amount of energy going to the bike (gas and displacement) and less coming out due to retarded timing. The energy is being dissipated in the engine....aka, its hard on the engine. Its not like you are tuning flow like with jetting or cams to get more gas and air in and thus producing more power. This scrubs power but loading the crankshaft wrong. Just be careful.

Remember its ok when the throttle stop is in, the mapping changes in the second half of the rev's where the throttle stop was not allowing you to go.

[CORider63]

The reason it produces less power is because it retards the timing. I think it is just harder on the engine. It is basically slamming the crank at a less than optimal time. I think it is actually harder on the crank shaft and crank shaft bearings. There is is same amount of energy going to the bike (gas and displacement) and less coming out due to retarded timing. The energy is being dissipated in the engine....aka, its hard on the engine. Its not like you are tuning flow like with jetting or cams to get more gas and air in and thus producing more power. This scrubs power but loading the crankshaft wrong. Just be careful.

Remember its ok when the throttle stop is in, the mapping changes in the second half of the rev's where the throttle stop was not allowing you to go.

No, actually it's igniting after it gives the piston a "running start."

[mvryder]

So does that mean no ill effects? I am asking because it sounds like I have he wrong idea.

[CORider63]

So does that mean no ill effects? I am asking because it sounds like I have he wrong idea.

Just reduced power due to retarded ignition timing.

[mvryder]

So that means ignition after top dead center or before? Essentially late ignition right?

[dirtysouth]

YUP-I.E. less pressure in the chamber during ignition so in terms of fireworks...more like a lady finger rather than the good ole' cherry bomb

[William1]

Both the YZ timing and WR are before TDC, just slightly. The YZ is more before TDC (hence 'advanced'). The greater advance gives the fuel a little longer to burn, ideally making maximum BEMP just as the piston crosses TDC, maximizing the power stroke. The advanced timing is not at all damaging. It could cause a little extra wear, but the amount is insignificant. The reason a WR has a more retarded ignition is to make the engine more tractable and have a gentler power curve.

[Demo_Slug]

Do you guys know if it, the grey wire mod,

will affect off idle throttle response with small throttle inputs?

[William1]

The WR mapping 'softens' the engine at all rpms.

[starfish]

So we all agree that the grey retards the base timing setting. But does it, all so affect the advance rate? For you old hot rodders that like recurving your distributor. With all the rain commiing I figure i might check the advance with a snap on timing light.w/ advance knob. It just a matter finding a way to check rpm.

[Demo_Slug]

so, this old post pretty much shows that the gray wire only comes into play after mid 6 or 7K RPM. but that was an older WR. so things could have changed.

https://www.thumpertalk.com/forum/showthread.php?p=334774#post334774