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Discussion Starter #1
Hey all,

I switched out my coolant this weekend with DexCool, instead of the green stuff, the fluid looked pretty healthy, no white globs or rusty colored stuff.

Anyway after I made sure I had the correct amount of fluid in it I started her up and let her idle with the choke on while sitting on the center stand. I noticed something slightly out of the ordinary. The back wheel, which was off the ground due to the side stand was slowly turning, I thought hmm never noticed that before.
Well I wheeled her out of the garage after this and put the bike on the side stand then I heard this weird noise.

The noise sounded like an intermittent rotating not really grinding but rubbing metal on hard surface noise, not overly loud but there nonetheless. It didn't make the noise constantly only seemingly at an undetermined RPM after revving it a little. This really concerned me b/c I've never heard this noise before. Next I took it around the block never getting above 2nd gear and varied my speed by accelerating and decelerating sometimes quickly other times not but wasn't able to get the bike to make "the noise". Sooooo I got back in the driveway, bike still not showing up to operating temperature, and still very intermittently the noise would re-occur.

I'm thinking that it probably isn't the ACCT because that noise would be constantly occuring upon acceleration and de-celeration right?? And if it were the ACCT wouldn't it sound similar to a loose chain slapping the chain guard on a chain drive bike???

OR is this that "coffee grinder noise" I've been reading about??

Any thoughts???
 

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Noises are so hard to diagnose. ACCT's generally make noise all the time.
The "coffee grinder" noise almost always goes away after the bike has warmed up.

All you did was change the coolant and this started?

Jon
 

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The coffee grinder noise from the clutch usually only happens when letting the clutch out, not while sitting at idle. Can you determine where the noise is coming from? It may be the water impeller or related part as the only thing you did was change antifreeze.
 

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Discussion Starter #4
All I did was change the coolant I swear.

As far as I can tell the noise is coming from the right side of the bike maybe near the righthand footpeg?

When I was changing the fluid I also took out and replaced the top bolt to the radiator plastic cover. Is there any way I could've tightened it too much and now the fan is knocking against it when it kicks on?? I know the fan is on the inside of the radiator but ????
 

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All I did was change the coolant I swear.

As far as I can tell the noise is coming from the right side of the bike maybe near the righthand footpeg?

When I was changing the fluid I also took out and replaced the top bolt to the radiator plastic cover. Is there any way I could've tightened it too much and now the fan is knocking against it when it kicks on?? I know the fan is on the inside of the radiator but ????
The fan is behind the radiator and I doubt it has even come on under those conditions. The plastic cover can not contact the fan.

The area you describe is near the water pump. Are you sure you have all the air out out of the coolant system?

Jon
 

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Discussion Starter #6
No I'm not sure that all the air is out. I let it run a little to see if the fluid level fluctuated but it didn't. It never got up to operating temperature so maybe that's the issue. Maybe I should let it get up to temp., then let it cool down and THEN check the fluid.

Would this help eliminate the air bubbles???
 

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No I'm not sure that all the air is out. I let it run a little to see if the fluid level fluctuated but it didn't. It never got up to operating temperature so maybe that's the issue. Maybe I should let it get up to temp., then let it cool down and THEN check the fluid.

Would this help eliminate the air bubbles???
There is a bleed screw behind the radiator cap (towards the rear of the bike) that you should open to let the air out while filling.

Jon
 

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Discussion Starter #8
Okay ooops didn't know anything about that???

It's located behind the cap (towards the rear) and not part of the actual cap?
 

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Thanks Dianna I'll try to do that tonight.

I'm assuming it's visible without the tank off???
yes, sadly. but to get the tank off its fairly easy. takes about 15 mins to take it off and 20 to put it back on.
 

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Discussion Starter #12
Okay the bike is still making that damn annoying squeaky noise, since I changed the fluid. I did two out of the three ways that have been mentioned on this board for eliminating air in the coolant lines but the noise still happens.
This weekend I got to wash and give her a good wax and I was letting it idle in the driveway with the radiator cap off, for just a minute or two, and gave the hose at the bottom of the radiator a squeeze to hopefully eliminate any remaining air in the system. Then the noise happened louder than I've ever heard it, so loud it made me paranoid enough to shut off the bike. After I let it sit for a minute I started it up again and went around the block, with very little noise at all.

As far as I can tell it is coming from the right side underneath the circular cover, sorry can't think of what it's called at the moment. As described before it sounds like an internal metal on metal repetitive circular rubbing sound. Though not the same sound it reminds me of a box fan/radiator fan constantly hitting the fan guard, but with a higher pitched more solid sound.
It seems to happen within the first 10-15 minutes of the ride then goes away but comes back the next time I ride it. This "noise" has NEVER been present before I changed the coolant.

Any new philosophies on this one???????????????? Please tell me I have nothing to worry about?
 

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humm... well the grinding clutch from what i understands only occurs on accel/decel b/c the friction plates are slipping. Since the sound only started once you changed over to dexcool, i would have to say that is your culprit.
1) did you make certain you got the correct mixture of distiled water and coolant?
2) did you flush the system? when dexcool mixes with regular coolant, a sludge can form.
3) which circular cover on the right, the front one, or the back one? the back one houses your clutch basket. Try putting the bike in neutral on the centerstand and start it. then put it in gear. does the sound change? is the sound rpm sensative?
 

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sometimes when doing one thing to any machine another thing goes wrong with it which has nothing to do with what you were repairing or servicing in the first place. i can't think for any reason why changing the coolant would cause a noise by the clutch cover. i might just be inclined to remove that cover and see what's happening in there. maybe a piece broke off and is causing that noise. its worth a try and all you are realy doing is remoing a handful of screws. if its nothing, just put the cover on and look for something else.
ride em safe J
 

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Noises

John,
Sorry you are having issues with your ride. Hang in there- I'm hoping its one of those simple fixes. For what its worth, I recently changed my coolant to the orange Dex-Cool and did not have any issues. I flushed and filled (and filled, and filled) slowly to make sure all the air was out of the coolant system. If you see your clutch is OK, give the cooling system some attention by squeezing the coolant hoses plenty and refill again, all to make sure the air is all out.

Good luck.
 

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The noise you're describing certainly reminds me of every waterpump I've ever had go bad in a car or truck in my life, and I've had plenty!

Free Wheelie is certainly making sense here though. I've had that happen a few times too, where something not related decided to act up right in the middle of me doing something else to the bike.
 

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on second thought, i have to agree with Fregy. i bet its water pump related. take a look at oil and make sure there is no coolant mixed in. this will eliminate the water pump shaft seal. but i think you have to inspect that impeller to see if that is the cause. good luck

J
 

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I like the impeller idea too. I've run Dexcoll in everything for years, thats not the problem.

Perhaps something has come loose from within your coolant system and it either broke one of the blades off the impeller, or has become lodged near the impeller making the noise.

Not clutch, pull that cover and check the water pump.

Jon
 

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The impeller is a pretty simple device. It just spins on the shaft to pump coolant. If it threw a blade, there would be more than a grinding noise, the engine would sound like it's coming apart. There isn't much room in the pump area so the blade would bounce around as the rest of the impeller spun around.
However, it won't hurt to check it out. The only other thing I can think it could be is that when you changed to Dexcool, some corrosion that was already on the impeller shaft came loose and is causing the grinding sound. If the bike sat for a long time with bad coolant in it, that could happen. Mine was full of crud when I tore it down.
 
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