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Discussion Starter #1
I know there are 50 jillion threads out there on drive belt noise. Well this is one more. 2 weeks after getting a new tire installed my belt started to chirp. I took it back knowing it was the belt. They worked at it over an hour before they got it to quiet down. When it would chirp it was only under Acceleration. The tech said he had to loosen up the belt some. I have found threads where people went a little more loose than specs for the noise so I had no problem with that.

Fast forward about 1200 miles later. I am on a long ride with the wife and I hear it again.. This time on accel and decel. Well fudge. I never bought the tension tool so I had to take it easy, get her back to the shop and park her. I let it sit for a day. I took her for a ride this morning so I could try a couple of the tricks I read about. No noise.. Grrrrr. So my thought is with her on the back it put more tension on the belt with the compression of the suspension. Any thoughts or advice on this?

I just ordered a belt tension tool I am going to check it myself.

ALSO can someone please tell me if the 950 belt is supposed to ride center or left side of the pulleys? I have not found a conclusive thread on this.

A ton of threads were people who could not get rid of the noise and just put wax on the outside edge of the belt.. I am not good with putting anything on my belt.
 

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Here is the facts on the belt position on the V Stars. The belt will ride toward the outside edge (but not rubbing) of the rear pulley when moving forward when the tire is aligned properly The front drive pulley and rear drive pulley are not in the same plane. The rear drive pulley sits further inside the bike than the drive pulley does.

The 950 calls for 3mm-5mm of tension from the factory which is way too tight, and yes way too tight. This will eventually lead to rear drive pulley needle bearing failure. Also check that the front pulley nut is not loose, and the washer behind it. There have been cases of where the front drive pulley nut was not torqued to speck, but they are staked so they don't move, but the washer underneath does and this will cause the front drive pulley to wobble and eventually destroy the output shaft splines.
 

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Discussion Starter #3
I have a tool to check chain alignment on the other bike. How do I check belt alignment on this one?
 

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I have a tool to check chain alignment on the other bike. How do I check belt alignment on this one?
You mean wheel alignment, proper wheel alignment adjusts the belt track and belt tension. Here are a couple of videos of a guy doing a raider, a little different, but same concept.





 

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Discussion Starter #5 (Edited)
Okay, I measured belt deflection at 10lbs today and got 11.5mm while on the side stand. I need some belt experts to kick in their thoughts here. Do you think that is too tight? If it goes any tighter I know it will squeal. I found several threads on here talking about replacing belts fixing the issue. How hard is it to replace?
 

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Discussion Starter #6
Okay, I just went out there and looked at the alignment. It was off by about 1 to 1.5mm. I do not know if that is enough to cause noise, but I made it as perfect as my eyesight could. I went with the left side a tiny bit more loose rather than tighten up the right side. I won't be able to ride it for a couple of days to see if that fixed it. I will update.
 

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11.5 mm is a little loose for the 950. 5mm to 7mm would be better. If the belt is too loose will skip and shear off the belt teeth. Squealing or whine is too tight, chirping is usually too loose.

The Yamaha specs for the 950 is 3mm to 5mm which is pretty tight, 5mm to7mm is a better tension to have and wheel alignment is important as well.
 

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yamaha dealerships/service shops have been notorious for tightening the 950 drive belts too tight; they probably used to all come from the factory too tight to begin with. 5mm-7mm seems to be the sweet spot for this model in belt tension. i only got about 30K miles on my first belt before i started hearing the squealing. turns out that particular belt was defective to the tune of being stretched out too much. crazy. could have been the effective of always being waaay over-tightened. my current belt has over 50k miles and i just started hearing the squealing again a week ago. i had my tires changed in the fall so i hadn't checked my belt tension since then, but the play was over 10mm. so i tightened it back up to 5mm and problem solved.
 

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Discussion Starter #9
I have the slack at 7 mm right now. I do not hear the squeal unless I 2 up and even then it takes over 30 miles of riding before it starts. Any thoughts?
 

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Discussion Starter #11
I fixed the wheel alignment. It was off a couple MM, as long as the marks are correct.
 

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Discussion Starter #13
I might have to beak down and get a new belt, as this one was strung guitar tight at one time that I know of. It may be too late for it. 20k miles
 

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Discussion Starter #15
Scratch the it only makes noise when 2 up. I rode her hard this past weekend.. 80+ for a lot of miles. When I got done she was singing up a tune. I talked to another 950 rider at the meet I went to. He says he just lives with it. I found several people who put candle wax on theirs. I got to thinking, I do not like putting anything on belts because I am afraid of it breaking down the rubber of the belt. Then it hit me. CHAIN WAX. It is designed not to hurt the rubber O-rings of the chain. Sooo I put a little on the left side of the belt. For those that have never used a can of chain wax, it sprays out very slow and is very precise so you do not have to cover everything. I went on a short ride and it did not squeak. I have it set to 6mm. It is dead nut on with the marks. I just cannot bring myself to pay over 400 dollars for a fckn belt.
 

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Discussion Starter #17
The chain wax did eliminate the noise, but I traded it in after about 1500 miles. So I do not know how long it lasted.
 

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well i started experiencing belt noise again myself a few months ago. tried rubbing a bar of soap along the edge of the belt which eliminated the noise for about 100 miles, tried washing the belt with dish soap which worked for about 20 miles. then i used chain lube, which i assume is pretty close to chain wax because that's what the parts store had and i didn't feel like searching another place for chain wax. it sprays out pretty much like a can of WD-40. i coated the whole left side of my belt with it and have killed the noise for about 1,000 miles so far. don't know why my belt started making noise. it's got 50k miles on it but there are no other symptoms or issues. my previous belt had 30k miles on it when it began making noise, but it also started slipping soon after and necessitated a replacement. so far i haven't had any other issues since spraying the chain lube.
 

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Discussion Starter #19
It depends on what you got, some of the chain lubes are a wax.. possibly all of them.. lol. Glad that is working out for you though.
 

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you would think for the cost of these motorcycles yamaha could get the belts to track down the middle of the pulleys, i hardly ever see a motorcycle without the belt being to one side or the other, it's like the wheel hub spacers are never perfect or the engine is too far in or out, maybe a combination of both?
 
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