I HAVE A '99 SCRAMBLER 400. WHEN IT IS IDLEING THE BOTTOM END OF THE MOTOR SOUNDS EXCESSIVLEY LOUD. IT SOUNDS LIKE YOU CAN ACTUALLY HEAR THE PARTS SPINNING.

ITS KIND OF HARD TO EXPLAIN THE DEGREE OF LOUDNESS ON HERE. I KNOW MY LAST QUAD, AN LT250R WAS KIND OF THE SAME. IT WAS LOUD, LIKE YOU COULD ACTUALLY HEAR THE PISTON GOING UP AND DOWN.

DOESN'T SEEM LIKE ANYTHING ABNORMAL. CAN ANYONE TELL ME, HAVE YOU NOTICED THIS LOUDNESS. OR SHOULD I CHECK MY GEARCASE OIL? I HAVE BEEN MEANING TO FOR A WHILE, BUT I DON'T HAVE A GARAGE AND ITS BEEN QUITE COLD OUTSIDE. I HAVE OWNED THE QUAD FOR A YEAR THIS MONTH. I KNOW IT SHOULD BE DUE FOR A CHANGE OF THE GEARCASE OIL.

ANY SUGGESTIONS?
THANKS

BIGDEVIL '99 SCRAMBLER 400 W/RCR STAGE 1

 

If I had to guess , I would say the clutch buttons are worn out of the primary clutch , remove the cover and take a look .

A light chatter at idle indicates piston to wall excessiveness ussually . Check the clutch first , it is easier .

 

Yes, I noticed it too...

I also have a 99 scrambler 400. It only has about 10 hours on it, so the engine should be in great shape. After I put on the RCR stage one kit, I noticed the loud engine noise at idle just as you did. While the new pipe is louder also, the major engine noise is now coming from the air intake (assuming you put on the stage one air cleaner kit). I finally put the air snorkel back on (with the mods in the instructions), which quieted it back down a bunch. I agree with you that the engine sounds MUCH louder at idle with the RCR kit.
Good Luck,
Lorrin

 

Also check your counter balance oil in it to see if water got in. The oil would be a milky color. If it is milky there is a chance the braering have gone out. Have seen 2 400 have this happen

 

Mine was making a lot of noise ( rattling or knocking ) that was noticable from idle up through the rev range. I pulled the exhaust pipe off and saw the piston had scored on both the exhaust and intake sides.
A new 0.040" oversize Wiseco was the cure to all of those problems.

 

My 400 seemed to be doing that as well, Only when it was warming up and usualy only in cold weather

 

Same thing here Most be normal.99 400 scram.

 

The noise on my Scrambler at idle turned out to be piston slap. It finally shattered the piston.
I wouldn't ride it too much til I knew if it was the clutch or the piston making all the noise.

 

I hope it is normal! both of mine have this noise. It is much more noticable on mine with the pipe, you have to listen for it on the wifes stock bike.

 

Well while we'er on the subject of ticking/knocking sounds, do any of yall hear a clicking sound that seems like its coming from the recoil??? Just wondering, dont think there is anything wrong with it cause it runs like brand new.