Noise that worries me, 2007 WR450F

[galmarrmd]

I have been riding very infrequently over the past couple of years and yesterday was first time out this year.  The bike overall ran fantastic but it occasionally made a noise that makes me nervous.  I know noises are hard to explain but here goes:  whenever I hit it hard in the taller gears and rev'd it out momentarily, as I dropped off WOT I would get a split second chattering noise, it makes me think of a dry bearing noise, and seemed to come from the top end but at  50+ mph on a rocky logging road  that's hard to be sure of.  I put on 80 miles in the mountains yesterday and otherwise it ran great and the noise never got better or worse during the outing. I recalled hearing the same noise during some previous rides as well.

 

I've owned the bike for 6 years and bought it from a older dual sport type rider who seemed to be very fussy and thorough so I'd say the bike has had a pretty easy life and is now at 6700km/4000 miles of mostly mountain road and trail riding.  As an older guy it has plenty of power for me  so I don't need to bag on the motor to make it go fast enough.  However I like to crank it on an uphill section, roost off the odd corner or loft the wheel over a creek or waterbar so that is usually when my short duration WOT happens. Everything external is tight so its not vibration as far as I'm concerned.

 

I have an aluminum skid plate underneath so I am accustomed to the overall noisy engine sound bouncing back up at me, but this is different and pretty noticeable so this sporadic noise has me a bit worried.  If anyone could shed some light or offer suggestions for me it would appreciated.

[FORMA MOTO]

If you have not put a large bead of silicone under your swingarm chain rub strip, it will slap against the hollow swing arm and make very scary noises....and it will rub a hole right through the swingarm, if you wait long enough...

[galmarrmd]

Never heard of this, this is the nylon piece at the front of the swingarm that wraps around top and bottom? 

[FORMA MOTO]

Never heard of this, this is the nylon piece at the front of the swingarm that wraps around top and bottom? 

 

Yes

 

It will litterally pound a hole in the top of the swingarm if you don't insulate from the swingarm......and it makes the 'chain slap' noise.

[ttreewalkerr]

Don't mean to scare ya, but my bike would make a sound every time I let off the throttle, no load. Fine at idle, but give it a rev and as it came down you could hear it. Road it for a year like that,,, then 2 weeks ago on a tight woods ride it got loud, took roads back. Tore into it,, crank bearing. Must have put on 600 miles before I said oh shyt, never seized just got loud. Noticed balancer shaft bearing in there was starting to get that skateboard sound, so I replaced a few bearings in there, rod bearing too since shavings got into everything.

[RC81]

If you have not put a large bead of silicone under your swingarm chain rub strip, it will slap against the hollow swing arm and make very scary noises....and it will rub a hole right through the swingarm, if you wait long enough...

 

I bet thats the noise your hearing too. My 05 does the same.

[AKmud]

Just dealing with this myself.  The noise has me second guessing my chain tension every time I ride the street.

[galmarrmd]

If you have not put a large bead of silicone under your swingarm chain rub strip, it will slap against the hollow swing arm and make very scary noises....and it will rub a hole right through the swingarm, if you wait long enough...

I  visually checked the chain guard piece as recommended by Krannie, it is not overly worn by the chain and there is no sign of the chain hitting the swing arm, however the piece does move around a bit on the swingarm.  So if it's position is not supposed to float a bit, then I'll remove/clean and 'glue' it in place with a silicone type product.

[ttreewalkerr]

If it's the clank of the chain, you an tell it's the chain. That clank doesn't transfer to sound like top of motor noise.

My crank bearing sound,,, I would have bet 50 bucks it was my top cams or cam chain, that sound did transfer.

[galmarrmd]

I sure hope you're wrong TTree and it did not sound like chain slap to me. Last night I disassembled and cleaned the chain guard and swing arm, there was no wear to the top of the swing arm at all but I bedded the guard into a base of sealant  as per Krannie just in case, so now it will not move on the swingarm nor let dirt underneath.  I then went over every fastener up front an found the forward screw on the header pipe heat guard loose so my fingers are crossed that the heat guard was vibrating slightly at a certain engine harmonic.  Hopefully I get another ride in this summer to report back.  Thanks all.

[ttreewalkerr]

So at idle you don't hear nothing odd. What about at idle, if you give a easy increase and let off,, as rpm come down any odd thunk thunk ?

[AKmud]

I pulled my chain guide off and was surprised at how much wear there was on the swingarm under it.  Siliconed it up tight, hopefully it will cure my chain slap noise and won't grind on the arm any more. 

[GASKICKER]

I sure hope you're wrong TTree and it did not sound like chain slap to me. Last night I disassembled and cleaned the chain guard and swing arm, there was no wear to the top of the swing arm at all but I bedded the guard into a base of sealant  as per Krannie just in case, so now it will not move on the swingarm nor let dirt underneath.  I then went over every fastener up front an found the forward screw on the header pipe heat guard loose so my fingers are crossed that the heat guard was vibrating slightly at a certain engine harmonic.  Hopefully I get another ride in this summer to report back.  Thanks all.

Take it for a rip down the street, you will know quickly if you fixed the chain slap.

[galmarrmd]

Don't mean to scare ya, but my bike would make a sound every time I let off the throttle, no load. Fine at idle, but give it a rev and as it came down you could hear it. Road it for a year like that,,, then 2 weeks ago on a tight woods ride it got loud, took roads back. Tore into it,, crank bearing. Must have put on 600 miles before I said oh shyt, never seized just got loud. Noticed balancer shaft bearing in there was starting to get that skateboard sound, so I replaced a few bearings in there, rod bearing too since shavings got into everything.

 

 

Don't mean to scare ya, but my bike would make a sound every time I let off the throttle, no load. Fine at idle, but give it a rev and as it came down you could hear it. Road it for a year like that,,, then 2 weeks ago on a tight woods ride it got loud, took roads back. Tore into it,, crank bearing. Must have put on 600 miles before I said oh shyt, never seized just got loud. Noticed balancer shaft bearing in there was starting to get that skateboard sound, so I replaced a few bearings in there, rod bearing too since shavings got into everything.

 

now I'm spooked - got out tonight for an a quick evening ride.  The noise is happening when coming off throttle whether sitting in neutral and blipping the throttle or running through the gears.  Oil looks clean and bike runs great under load, just this noise off throttle  and it seems 'strong' enough to make me think its crank bearings vs cam shaft bearings.. Any advice would be appreciated, or else do I just start tearing in looking for the first rough feeling bearing?  I'd sure like this to be a winter project if I felt it could last for a few day rides.

[ttreewalkerr]

There is one check you can do for the mag side bearig. Take off the side cover, you will be able to get your hands on the flywheel,,, leave it on,,,, take out your spark plug. Now pull up and down on the flywheel, should be NO play,, now rotate the flywheel and hour rotation, pull up down,, rotate it again,, pull up down. If a ball in the bearing cage is delaminating you will eventually feel the clunk. The other side,, clutch side you can do the same by grabbing the clutch basket. When you hear that clunk coming off of rpm, I was noticed a very Suttle feeling in the bars from it too, very suttle.

If it's running fine it's probley 1 ball delaminating, and making a brunel pit in the raceway. After looking at mine I could see a pit forming in the inner racway. This is usually caused by an inclusion in the steel,, carbon flake. Clean steel is key for bearings,,, KOYO is who Yamaha buys their motor bearings from.

My motor did give some metal up to the oil filter when that noise was there. And I did just run it until it got BAD. It cost me the cylinder buy doing that, eventually the shavings got between piston and cylinder wall. If I would have caught it before that would have saved me 300 bucks on that cylinder.

So sell it now, if your capable fix it. The bearings are cheap, and do all of them while your in there,, piston kit is 150 bucks.

Use heat and swifter spray to chill things to get those bearings out. For assembly use your freezer for brearings and heat for the case.

[SuitcaseDW]

Lotsa noises from a wr being beaten over rocks and loose surfaces...I found my "nasty noise" that was bugging me for several days. The front brake caliper is very loose on its sliders on the fork tube and the rotor is even looser on the front wheel...so its tool time,