HELP - Vibration / Harmonic at slow trail speeds, 5000 rpm

[mbarryracing]

Not sure if this is common and I'm just being anal.
I have only 230 miles on my 06 GT now, when running about 15-20 mph at about 5000 rpm thru the trails I am feeling a high frequency harmonic / vibration. (in powder or on hardpack).
Feel it in the handle bars and in the floor boards. Can hear the dash buzzing too. It goes away with an increase in RPM and speed, also seems to go away just as the clutches disengage when rolling to a stop.

144 studs in the middle, all the wheels are new (I had replaced all the junk stock idlers with the spoked Yamaha's this weekend).
No ice build up, does it right off the trailer.
Does this sound like maybe the track, or should I be looking for a bearing or at the clutches?
The belt looks good and the track is true, running it looser than the Yamaha spec, but tight to where I can still move it easy by hand.
Could be the exhaust resonance, this thing really has a drone to it around that RPM and speed, too.
Any thought?

 

[BADSLED]

It looks like your maybe the culprit. I would try another belt before you start looking at anything else..

 

[mbarryracing]

It looks like your belt maybe the culprit. I would try another belt before you start looking at anything else..

Thanks, I was going to try my new spare belt. I just scotchbrited all the release agent off it.
I can't remember if this vibration was always there and I am just tuned in to it now, or it just recently started. It just doesn't seem "right" to be normal for the quality of a Yamaha... I was told that these engine DO have an inherent hum about this RPM range, but I am investigating more...

I am picky and meticulous, but if I can eliminate this vibration, I'll probably never shut it off!

 

[ROCKERDAN]

the harmonic noise from the 4 cyl apexs is normal.....i still cant stand it,and it makes my ears ring sorta at lower speeds on trails....rode the new nytros and they DO NOT have the same buzzing sound on tunnel.

IMO it has to do with the exhaust vibrations on the tunnel....its the only thing on this sled that drives me nuts,and not sure if it can be stopped.

I decided to install speakers into my helmet a few yrs ago,and always ride with my mp3 player on.....which helps with the harmonic noise the apex gives off.

Dan

 

[mbarryracing]

Dan,

Thanks for calming my fears of a mechanical whoa...
That has to be the only single complaint I have about this machine. I wish the trails around here were faster so I wouldn't have to ride in that drone so often.
Have u heard if there have been any mechanical repercussions from that exhaust resonance? Seems like it would eventually destruct something. Oil tanks cracking? Exhaust system fatique?
Hmmm.

 

[nb-attak]

dash buzzing comes from (at least on mine) hood.
the hood's front mount is just sitting on an aluminum tube. If your driving slow and hearing that annoing plastic buzzing , try to put pressure on hood with your left hand while still driving. The annoying buzz sound disappears. Maybe putting a tin rubber hose spit in two on aluminum pipe would stop the front of hood from vibrating. Heck im going to hardware store to give it a try.

 

[mbarryracing]

nb-attak,

Front hood, meaning the "V" shaped cover?

Let me know how that rubber works!

 

[greenmntpass]

When I got my RTX I noticed the play in the front "V" hood where it slides over the front bar. Wrapped the bar with tape to minim. play and vibration gone. I agree with Dan about the duel exhaust being the culpritof the harmonic noise you here at slower trail speeds. I think I read a post here last season where one member purchased an Excell exhaust and mentioned that the harmonic noise had lessened or gone away. The Excell exhaust being one pipe versus two. In any case that noise is annoying.

 

[mdkuni]

dash buzzing comes from (at least on mine) hood.
the hood's front mount is just sitting on an aluminum tube. If your driving slow and hearing that annoing plastic buzzing , try to put pressure on hood with your left hand while still driving. The annoying buzz sound disappears. Maybe putting a tin rubber hose spit in two on aluminum pipe would stop the front of hood from vibrating. Heck im going to hardware store to give it a try.

I used a foam type weather strip that has adhesive on the back. Placed a small stip on the part of the hood that goes onto metal bar. No more noise from the hood!

 

[number1kyster]

When I got my RTX I noticed the play in the front "V" hood where it slides over the front bar. Wrapped the bar with tape to minim. play and vibration gone. I agree with Dan about the duel exhaust being the culpritof the harmonic noise you here at slower trail speeds. I think I read a post here last season where one member purchased an Excell exhaust and mentioned that the harmonic noise had lessened or gone away. The Excell exhaust being one pipe versus two. In any case that noise is annoying.

Greenmntpass,

I was up at Texas Falls Sunday riding and I heard an rx-1 with an excell exhaust. The sled sounded awesome, real quiet at low RPM and it had some bark when he punched it.

 

[greenmntpass]

Hey Kyle,
How's it going? Our crew was up there Sat. morning. Went to Pittsfield for breakfast, and did the Bethel Braintree loop. Wasn't too bad considering.
I spoke with Aaron at Excell last week and I'll have one next month. Pray for snow!!

 

[mbarryracing]

When I got my RTX I noticed the play in the front "V" hood where it slides over the front bar. Wrapped the bar with tape to minim. play and vibration gone. I agree with Dan about the duel exhaust being the culpritof the harmonic noise you here at slower trail speeds. I think I read a post here last season where one member purchased an Excell exhaust and mentioned that the harmonic noise had lessened or gone away. The Excell exhaust being one pipe versus two. In any case that noise is annoying.

Thanks guys, I am relieved that this is not a mechanical issue that could go all catywompus on me at the most inopertune time.
I would love to get rid of that exhaust drone, aftermarket system will eliminate that?
Anyone have feedback on the Bender exhaust? or is Excell the ticket?

 

[mbarryracing]

I took the belt off and lightly ran it up thru that rpm range, looks like an inherent harmonic in that Apex crank?

 

[number1kyster]

Hey Kyle,
How's it going? Our crew was up there Sat. morning. Went to Pittsfield for breakfast, and did the Bethel Braintree loop. Wasn't too bad considering.
I spoke with Aaron at Excell last week and I'll have one next month. Pray for snow!!

When you get that exhaust let me know. I want to meet up somewhere to listen to it and maybe drag the 2 sleds to see how much of a difference there is.

Todd, check this out. Its the excell on an attak.

http://www.youtube.com/watch?v=x8VSzCS5ca8

 

[170plus]

i was out tonight on my 06rtx with gutted exhaust with my 7 yr old,i let him drive while i was on back and he hit 21 mph and it stayed there for about a mile and my eyes were starting to cross,i never go that slow for more than a second at a time so never bothered me but its normal