Drive belt deflection-Is this normal
#11
Join Date: Jun 2007
Location: People's Republic of Boulder Colorado
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Ride at highway speeds for a few miles and pull over and feel the rear pully. If it's hot to the touch, then the belt's too tight. My experience has always been that if set to book spec, then it's usually on the too-tight side. These belts don't have to be tight as a guitar string. Just my 2 cents.
#12
I adjust looser too but go even beyond the range specified in the manual. If I adjust my bike to spec (1/4-3/8" cold) it will be like a banjo string when hot, so I set it to 9/16" cold, and that translates into about 3/8" when hot. That is the tension I used on my '96 RK and at 120k miles it is still running the original belt, so I guess this tension is adequate.
#13
Iclick,
Mine is tight as a banjo string when hot but seems to be in spec when cold. I have a noise that appears to come from the drive line when the bike is hot, my dealer hasn't heard my noise but from my description he says this noise is normal and comes from the primary. I'm having a hard time believing it is coming from the primary because the frequency of the noise changes with the speed of the bike and quits when the bike is stopped, if it were the primary wouldn't the noise continue when the bike was stopped since the primary is constantly moving with the rotation of the motor. Also when your drive belt was tight as a banjo string, did you hear any rubbing noise from the drive line?
Thanks
Mine is tight as a banjo string when hot but seems to be in spec when cold. I have a noise that appears to come from the drive line when the bike is hot, my dealer hasn't heard my noise but from my description he says this noise is normal and comes from the primary. I'm having a hard time believing it is coming from the primary because the frequency of the noise changes with the speed of the bike and quits when the bike is stopped, if it were the primary wouldn't the noise continue when the bike was stopped since the primary is constantly moving with the rotation of the motor. Also when your drive belt was tight as a banjo string, did you hear any rubbing noise from the drive line?
Thanks
#14
I too used to worry with this adjustment years, and years ago on my new 86 Classic. Let me tell ya, it ain't rocket surgery or brain science. Just be sure that there is a "little bit" of slack in the belt when it is HOT, and you'll be OK. And do not worry about all of the little noises ya here. 99% of them are normal on a Harley!! I chased belt and pully noises untill it almost ran me crazy, all for nothing! Just enjoy the bikes. By the way, iclicks method of belt adjustment sounds really good too me!
#15
Join Date: Mar 2007
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Ron
#16
Iclick,
Mine is tight as a banjo string when hot but seems to be in spec when cold. I have a noise that appears to come from the drive line when the bike is hot, my dealer hasn't heard my noise but from my description he says this noise is normal and comes from the primary. I'm having a hard time believing it is coming from the primary because the frequency of the noise changes with the speed of the bike and quits when the bike is stopped, if it were the primary wouldn't the noise continue when the bike was stopped since the primary is constantly moving with the rotation of the motor. Also when your drive belt was tight as a banjo string, did you hear any rubbing noise from the drive line?
Mine is tight as a banjo string when hot but seems to be in spec when cold. I have a noise that appears to come from the drive line when the bike is hot, my dealer hasn't heard my noise but from my description he says this noise is normal and comes from the primary. I'm having a hard time believing it is coming from the primary because the frequency of the noise changes with the speed of the bike and quits when the bike is stopped, if it were the primary wouldn't the noise continue when the bike was stopped since the primary is constantly moving with the rotation of the motor. Also when your drive belt was tight as a banjo string, did you hear any rubbing noise from the drive line?
In May 2008 I installed my first E3 rear tire and adjusted the belt tension to the loose end of the HD specs (3/8") when cold. I soon left for a trip and along the way discovered the belt was very tight, even though I adjusted it properly cold. On that trip I noticed a whining noise for the first time that was speed-related as you have described, mostly between 35-50mph, and when I returned home I did some checking on belt tension cold vs. hot, the difference on my bike being around 1/4". After adjusting to 9/16" cold the whine was still there and any changes in belt tension made no difference, so I began to blame the new tire that was installed just before the trip. My noise also gets worse as things warm up but is present at all times, and hasn't gotten any worse in the ensuing year. Its tone is very similar to the noise coming from the auto-chain tensioner that can only be heard when at rest or slow speeds, which is normal, but that noise is RPM-related. I don't believe the two noises are related. I did notice that while on my trip to the Smokies, where the weather was much cooler, the noise was much less noticeable.
You are correct that nothing in the primary can cause a speed-related noise, as everything there relates to RPM. A noise as we are experiencing could only be the tire, belt, or a bearing (wheel, IDS, or the tranny output-shaft). The noise I'm hearing doesn't sound like a bearing and its tone and intensity doesn't change much with throttle input, which should be the case if the belt was the source, so that points to the tire. Also, I have sprayed dry silicone spray and a dry Teflon spray on the belt, as well as cleaning and running dry, and that makes no difference. The dealer says unequivocally that it is the belt and that I shouldn't worry about it, but I'm not so quick to place blame there.
As for the tire, moderate weaving from left to right on the road doesn't change the tone of the noise any or much, although heavy cornering to the left makes it quieter, louder to the right, but not significantly. That makes me think the tire is the #1 suspect, but I'm still far from sure. I let a friend, who's an ME with a very high mechanical knowledge, ride the bike and he thinks the noise is the belt--but doesn't think it is something to worry about. I'm not.
Gold Wing riders complain that E3 tires whine or groan, but most complaints are in corners. There are some isolated reports of noise at all times, even when riding upright, but these are few and far between. About a year ago while the bike was still in warranty I let an HD tech that I respect ride the bike and he said he didn't consider it a problem but that I should check with him if it got worse. It hasn't, so I'm just living with it. I still don't know the source, but the bike has been ridden for about 15k miles since I first noticed the whine/groan with no change over time. There is also no indication of a problem elsewhere, like metal shavings on the tranny drain-plug magnet that would signal a failing O/S bearing.
Last edited by iclick; 06-29-2009 at 10:38 PM.
#17
I too used to worry with this adjustment years, and years ago on my new 86 Classic. Let me tell ya, it ain't rocket surgery or brain science. Just be sure that there is a "little bit" of slack in the belt when it is HOT, and you'll be OK. And do not worry about all of the little noises ya here. 99% of them are normal on a Harley!! I chased belt and pully noises untill it almost ran me crazy, all for nothing! Just enjoy the bikes. By the way, iclicks method of belt adjustment sounds really good too me!
#18
PS. Iclick, thanks for your time and effort to reply to my post, very informative.
#19
Ride at highway speeds for a few miles and pull over and feel the rear pully. If it's hot to the touch, then the belt's too tight. My experience has always been that if set to book spec, then it's usually on the too-tight side. These belts don't have to be tight as a guitar string. Just my 2 cents.
#20
took my bike back to the dealer today they changed the rear tire bearings and the isd bearing. when i left it wasnt making the noise got on the interstate and got it warmed up started agian. got home pushed on the belt was tight as hell felt the belt couple hours later and its loose. but i dont think its the belt get tighter from heat shouldnt it expand with the heat. i believe its the gears that turn the belt getting hot and expanding. some people i talk to that have the same bike doesnt have this problem and some do so whats up with that . $20,000 for bike and only 5000 miles on it shouldnt have this problem the way i see it. just had to vent alittle. back to the dealer next week i guess .