2007 Yamaha R1 Key On YCC-I Stuttering Noise

Zer0Sum · Jul 30, 2008

R1 Riders,

When the engine is off and no key is in the ignition, when you go to turn on the bike by just rotating the key to on, the ECU tests the YCC-I variable length intake funnels, by making the funnels go up and down, and you can hear this, the sound normally sounds like a good crisp strong weep-weeeeeep.

Today, on my 07 R1, I noticed, that when I turned the key to on, the first weep sounded ok, but the second sounded like wepeepeepeeep. What sounded like a very stuttered and labored effort by the servo to get the funnels to come back down.

Then, when the engine is actually running, and you still have the key in the on position, and go to turn off the engine by using the red kill switch, after the engine stops running, you should normally hear the weeeeeep of the funnels placing themselves in position, but the same issue occured for me again, when I actually heard the same labored stuttered sound of the funnels moving, the same as I had heard before the key was rotated to on when the ECU tests the funnels.

Has anyone else encountered this problem, heard these stuttering noises, know of this issue, know what the solution is?

Thanks,

Zer0Sum

triplex76 · Jul 30, 2008

you are hearing the exhaust valve not the funnels sound, cause funnel sound is not a weeeeppp sond but a rumble similar one!

yankin&bankin · Aug 27, 2008

No, this actually isn't what he's talking about.

The YCC-I on mine does the same thing, and I've heard other 07-08s do it, also.

Apparently it's normal.

hooligan998 · Jul 30, 2008

Check the cable tension on your EXUP valve servo motor. Adjust if not in spec. You may also have an EXUP valve that is starting to stick. You should probably go ahead and service it while you're crawling around down there.

FWIW, like triplex76 said, the YCC-I variable intake servo is only a short quite "rumble" sound. Not nearly as loud as the EXUP servo motor.

Zer0Sum · Jul 30, 2008

Hooligan and Triplex, you both are absolutely correct, and I apologzie if I my post misleads anyone about the actual YCC-I system.

Today, I put the key in the ignition, left my hand on it with it still in the off position, bent way down looking right at the EXUP system, and then turned the key on, and sure enough the 'weeep weeeeeep' sound is coming from the EXUP servo moving the braided cable back and forth, making the exhaust valve move through its range of motion.

Interesting enough, when I did this when the bike is cold, the weep weeeep sound from the EXUP servo is fine, it's only after a ride and everything is heated up that upon ignition on, that the weep weeeep becomes a weep weeepeeepepepeep stuttered sound.

Perhaps when all the metal is hot and expanded, it is causing the servo or the object being moved by the servo to stick and bind. If that is the case, how is that fixed ?

What I am afraid of is that during a ride, when the exhaust pipes are at their heat load, that the EXUP servo is stuttering just like it stutters when being directly viewed, causing mal-performance during the ride.

Thoughts?

hooligan998 · Jul 31, 2008

Refer back to my first post. Service and adjust your EXUP. Should clear it right up.

maddox402 · Aug 7, 2008

everybody has this problem it seams like, i just had this problem last week, clean the conn. ajusted cables. fixed it

rccaulfield · Aug 27, 2008

Mine does the exact same thing but ONLY when i hit the kill switch with engine running! If i turn ignition with key it makes the usual noise!! Thats the design i reckon! Bike runs perfect!!

rccaulfield · Aug 28, 2008

Its the exup valve fluctuating- im sure theres a reason for it!! The funnels make a distinctive pitter patter sound-its not them............imo!

2007 Yamaha R1 Key On YCC-I Stuttering Noise

Top Contributors this Month

Recommended Communities