county Posted August 7, 2006 Share Posted August 7, 2006 I gotta 99 model that I bought with 3700 miles on it almost exactly 2 years ago. It now has 29000+ miles on it. It needs a CCT. Anyway, the last couple of times I have ridden the bike and got it "hot"...heat gauge showing the needle up there on them wiggly lines (not outta the range brackets or in the red) and ridden it at that temperature for a while, well, it starts making this dull knocking sound. And, on tour in the Mississippi Delta last week not only did it make this dull knocking noise but it also started making this high pitched whine. (Like maybe from the fan (?). I hear these noises at idle. Bike runs fine. Noises go away when bike is idling at lower temps. Anybody else experience this? Got any idea what it is? Quote Link to comment Share on other sites More sharing options...
Guest rockmeupto125 Posted August 7, 2006 Share Posted August 7, 2006 My guess is that its lash in your valve gear or clutch. Change the oil, and change the CCT. If its from the front, the whine is the fan that blows air through the radiator when it thinks you are going too damn slow. If its from the rear, the whine is the unit that blows air through its pie-hole when it thinks you are going too damn fast. Quote Link to comment Share on other sites More sharing options...
county Posted August 8, 2006 Author Share Posted August 8, 2006 Thanks. Quote Link to comment Share on other sites More sharing options...
SBBXX Posted August 8, 2006 Share Posted August 8, 2006 I agree the whine may be the fan. The other knock. You are not alone. I have it as do many other owners. Scared the shit out of me at first because it sounds (and FEELS) just like a bearing knock. It only happens when hot, and won't get any worse. If changing the CCT makes it go away, let me know. marty Quote Link to comment Share on other sites More sharing options...
bartonmd Posted August 8, 2006 Share Posted August 8, 2006 I have a theory on the "hot knock..." The cylinder walls are aluminum on this bike, right, not steel sleeves?? If this is true, then we know aluminum expands at a different rate than the steel pistons, so it could just be piston slap at idle as the cylinders get larger, faster, than the steel pistons? This isn't as much of an issue with most aluminum block'd cars, because most of them have steel cylinder liners, so the liner and the piston expand at about the same rate... just a theory... Mike Quote Link to comment Share on other sites More sharing options...
wrgoudy Posted August 8, 2006 Share Posted August 8, 2006 I have a theory on the "hot knock..." The cylinder walls are aluminum on this bike, right, not steel sleeves?? If this is true, then we know aluminum expands at a different rate than the steel pistons, so it could just be piston slap at idle as the cylinders get larger, faster, than the steel pistons? This isn't as much of an issue with most aluminum block'd cars, because most of them have steel cylinder liners, so the liner and the piston expand at about the same rate... just a theory... Mike I sure hope my XX doesn't have steel pistons too. Quote Link to comment Share on other sites More sharing options...
bartonmd Posted August 8, 2006 Share Posted August 8, 2006 I have a theory on the "hot knock..." The cylinder walls are aluminum on this bike, right, not steel sleeves?? If this is true, then we know aluminum expands at a different rate than the steel pistons, so it could just be piston slap at idle as the cylinders get larger, faster, than the steel pistons? This isn't as much of an issue with most aluminum block'd cars, because most of them have steel cylinder liners, so the liner and the piston expand at about the same rate... just a theory... Mike I sure hope my XX doesn't have steel pistons too. Edit: yep, nevermind... The XX's pistons are aluminum... That kinda shoots that theory all to hell doesn't it... Mike Quote Link to comment Share on other sites More sharing options...
wrgoudy Posted August 8, 2006 Share Posted August 8, 2006 As for the knocking noise at idle when hot, I believe the counter balancer adjusment may be the culprit. I've adjusted mine several times over 56K miles, but even when adjusted with the engine hot, the noise eventually returns once it's run long enough and gets truly heat soaked. I've been afraid to run the adjustments any tighter as I suspect there'll be too little lash when cold (which produces an audible whine), and I'm afraid excessive wear may result. I'll need to talk to a buddy running a full blown turbo motor that's had the counter balancers removed to see if his makes the noise that seems to be so popular. Any other ideas on possible sources would be appreciated. FYI - I have a 2004XX with about 56k that's been noisier than usual lately, although it runs just fine if you ignore the knock at idle. Changed the cam chain tensioner already, but did notice when I tore the clutch out last winter for inspection that the "dual offset" (don't remember the correct nomenclature) drive gear to the clutch basket seemed "sticky". Wasn't about to dig into that issue, but wonder if it's a contributing factor. Guess I'll reset the CCT and adjust the balancers once more to see if that helps. Quote Link to comment Share on other sites More sharing options...
lois Posted August 9, 2006 Share Posted August 9, 2006 As for the knocking noise at idle when hot, I believe the counter balancer adjusment may be the culprit. I've adjusted mine several times over 56K miles, but even when adjusted with the engine hot, the noise eventually returns once it's run long enough and gets truly heat soaked. I've been afraid to run the adjustments any tighter as I suspect there'll be too little lash when cold (which produces an audible whine), and I'm afraid excessive wear may result. I'll need to talk to a buddy running a full blown turbo motor that's had the counter balancers removed to see if his makes the noise that seems to be so popular. Any other ideas on possible sources would be appreciated. FYI - I have a 2004XX with about 56k that's been noisier than usual lately, although it runs just fine if you ignore the knock at idle. Changed the cam chain tensioner already, but did notice when I tore the clutch out last winter for inspection that the "dual offset" (don't remember the correct nomenclature) drive gear to the clutch basket seemed "sticky". Wasn't about to dig into that issue, but wonder if it's a contributing factor. Guess I'll reset the CCT and adjust the balancers once more to see if that helps. My 01 has a knock in the lower end, we tracked it down to the clutch, the knocking seems to be from the free play in the clutch basket and plates. Nothing worn out, everything seems to be to spec.....just gonna keep driving her. Quote Link to comment Share on other sites More sharing options...
The Krypt Keeper Posted August 10, 2006 Share Posted August 10, 2006 how did you get a 2004 XX in Penn. ? If you snuck it in, then I got a few wish list items I could use.. Quote Link to comment Share on other sites More sharing options...
bartonmd Posted August 10, 2006 Share Posted August 10, 2006 how did you get a 2004 XX in Penn. ? If you snuck it in, then I got a few wish list items I could use.. I was thinking that too, but figured it was the typical "uh, yeah... I've got one of those" Mike Quote Link to comment Share on other sites More sharing options...
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