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Rear wheel dragging when spun on stand


USMCFieldMP

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USMCFieldMP

So I went to adjust my chain earlier this week and after I was done, I spun the wheel to be sure there was no hang up. Unfortunately, there is one. It'll spin freely around for about 340°, but then it'll drag on something and come to a stop. So I tried re-adjusting the chain, thinking this might have been the issue. No dice, same thing. That's when I noticed that when it starts to drag, a piece on the axles starts to spin with it. Here are my pics, for reference:
 
Z9KstfT.jpg?1
 
pKBqmEF.jpg?1
 
 
My parts are a bit dirty, and therefor hard to see, so I'll borrow markster's wonderfully clear photo.
 
 
YWUHYc6.jpg
 
 
The part boxed in red is the part that I see catch and start spinning. Now, looking through the service manual, it would appear that this is a collar (p. 4-25; [HASH]14). I guess what I'm getting at is, has anyone else had this happen? Do I just need to pull the axle and grease it up (recommended grease; I know the SM calls for lithium-soap grease)? Or do I have a rear alignment problem?
 
 
Any insight would be welcome; please and thank you. I'm really, really good at working on and diagnosing cars, but this is my first bike, so I'm hesitant to do things without asking for a bit of guidance.

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That spacer should never turn, that spacer is part of the solid stack up of parts thru the sprocket carrier bearing inner race and its inner reducer/spacer, the lt. side wheel bearing inner race, the between wheel bearings spacer tube, the rt. side wheel bearing inner race, it's outer spacer (smaller dia. one you see in your pix) then finally the brake caliper mounting boss. Once the axle nut is torqued up all these parts are locked together. Has this wheel been off? I think I would make sure the axle nut washer is present and that you're not bottoming the nut out on the axle shank before it tightens up on the stack...Mark

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USMCFieldMP

I should clarify, that I didn't notice the spacer spinning when everything was torqued down, but rather when I had the axle nut loose to adjust the chain.
 
Once torqued, no, it doesn't spin... but the wheel still has the drag when spun.
 
The wheel assembly has been off once and it was sometime last October... maybe November... when I had the tire changed. I didn't notice this hang up until recently though, and I did tighten the chain back in March, as well.

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With the axle nut loose, this is a non-issue. The entire wheel assembly - bearings and spacers and all - will turn on the axle as there's no force squeezing them still.
 
A chain with a tight spot can cause your real symptom - especially if your chain is adjust w/o the proper slack.
 
A warped rear disk, or even a hard spot in the steel can also cause this. Take a magic marker and draw a couple of lines around both sides of the disk. If the rotor is rubbing, the marker will be rubbed off in that spot.Or just remove the caliper ans see if it goes away. There will always be some drag from the pads - even w/o any rotor defects.
 
 

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USMCFieldMP

Typically I'd agree, but that spacer only spun when the drag would occur and the wheel started to come to a halt.
 
Rear brakes are what I thought it was initially, but I'm not thinking so anymore. More checks to come; I'm probably going to tear the whole rear axle assembly apart soon. It was REALLY noisy when I took it for a spin today.

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With the axle loose, the wheel bearings are not really in use. The wheel, its outer and inner spacers are all turning on the axle. Think the axle can't turn cause it is keyed to that right side adjuster.
 
It's just not a valid test if that nut is not tightened to proper spec.
 
A bad wheel bearing will be bad all the way round. If it is dragging in the same spot thru every rotation, it's likely the rotor

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I'm probably going to tear the whole rear axle assembly apart soon. It was REALLY noisy when I took it for a spin today.
If you can hear a noise from the axle or rear brake when riding that's a real problem.
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USMCFieldMP

My thoughts exactly. Not only noise, but I can feel it in the seat. If the rotor is warped enough of course, that could be what I'm feeling... but my gut tells me that's not the case.
 

With the axle loose, the wheel bearings are not really in use. The wheel, its outer and inner spacers are all turning on the axle. Think the axle can't turn cause it is keyed to that right side adjuster.  
It's just not a valid test if that nut is not tightened to proper spec.
 
A bad wheel bearing will be bad all the way round. If it is dragging in the same spot thru every rotation, it's likely the rotor
 
I understand how it works and understand why it's not a valid test. I was just reporting what I saw. I have a very high mechanical aptitude and know that symptoms can help point to a conclusion though. Upon initial inspection, I don't see why that spacer would spin ONLY when a warped rotor was dragging the pads. I very well may be wrong and it's just a case of the wheel slowing down enough for the friction between the spacer and the rest of the wheel assembly to get to a point where the spacer finally spins. And like I said before, rear brake was my initial thought since it seemed the most likely candidate, but I've really felt like it was coming from the chain side.
 
I'm a pretty good problem solver, so I'll get to the bottom of it... I was just throwing out what I noticed. My first test tonight, however, will very likely be removing the caliper first to see if it still drags.
 
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USMCFieldMP

Rear brake is off. Still dragging.
 
New development though. I marked the tire when it started to drag, watched where it stopped dragging, and then where it started dragging again. I think the easiest way to explain this will be with the unit circle as reference.
 
So, imagine this circle as you facing the wheel from the sprocket side... 0 facing the rear of the bike... π facing the front.
unit-circle12_43204_md.gif
 
So I spun the wheel (as if the bike were moving forward) until it started to drag. I then marked the wheel at the 0π location. I moved it around until it spun freely again; this occurred when the mark was at π/2. It then freely spun around until it was right about at the π/3 position.
 
So with this, I'm guessing that this has nothing to do with the rear wheel and I'm 95% certain this is a chain issue. I'm going to pull the chain off and spin again, just to be sure though. I might mark the chain and see where it is when it starts to drag.

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USMCFieldMP

I guess I missed lubing a section of the back side of the chain some time. There were about 5 or 6 links that were pretty rusty on the tire side of the chain. Cleaned them as best I could and lubed it up. Still not right, but much better.
 
I guess I'll start looking into a new chain.

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I am glad you found the problem. Your previous post was giving me geometry class flashbacks. I am not sure I could have handled another one :)

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USMCFieldMP

Haha, sorry. I'm halfway through a Mechanical Engineering degree. Trig and Calculus are basically second nature for me.

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Haha, sorry. I'm halfway through a Mechanical Engineering degree. Trig and Calculus are basically second nature for me.
 
 
This is an interesting problem.
Did you happen to remove the chain to validate your hypothesis?
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The first post shows a lot of the chain adjuster's threaded stud sticking out the back of the swingarm.
How many miles on the drive chain, and how many times do you reckon you've made an adjustment?
 
In other words, it looks like the rear axle is pulled rearward a lot more than on my FZ07.
 

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A too tight chain will stretch unevenly and tend to have the grease forced out of the most stressed links, leading to a kinked chain. Better to err on the slack side when it comes to chain tension.

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USMCFieldMP
This is an interesting problem. Did you happen to remove the chain to validate your hypothesis?
 
No, once I figured out it was likely to be the chain, I paid complete attention to it and its rotation. The problem section caused the "drag" when it attempted to go around the front sprocket. Which makes sense; if it's rusty and doesn't have as much rotational ability, then going around the small diameter sprocket will be problematic.
 

The first post shows a lot of the chain adjuster's threaded stud sticking out the back of the swingarm. How many miles on the drive chain, and how many times do you reckon you've made an adjustment?
 
In other words, it looks like the rear axle is pulled rearward a lot more than on my FZ07.
 
I'm at 18,000 miles. I've made the adjustment twice, it made by Yamaha with the first service, and it was made by the guy that changed my rear tire, as well. So there have been 4 chain adjustments. I don't think I'm even halfway through the adjustment range either.
 

A too tight chain will stretch unevenly and tend to have the grease forced out of the most stressed links, leading to a kinked chain. Better to err on the slack side when it comes to chain tension.
 
That's definitely not the case here. If anything, this chain has been too loose for the majority of its life. Just a case of missing a spot when chain lubing... which on a bike that lives outside, isn't a good thing.
 
I hit it hard with Motul Chain Clean and a brush, then lubed it heavily. It was still rather noisy today
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If the seals are OK, lubing it is mostly to keep surface rust away and to let it run silently, because all the important lube is inside the rollers. But at 18k miles, it isn't unheard of that the seals start leaking a little, allowing water to get in and grease to get out. Especially if it has been hit with high pressure water or ridden a lot in the wet. So it could be just normal wear setting in.

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At 18k miles you might just want new sprockets and chain and be done with it, some people wouldn't recommend a new chain on 18k sprockets if they look worn at all, will decrease new chains potential lifespan. JMO
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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Didn't someone have o-rings on that OE chain break just by using a brush on them? Might not hurt to have a close look.
 
I'm still a fan of cheap gear oil with a little white Li grease mixed in for some extra sticking power. What little that flings off is easy to clean and it takes dirt with it from the chain. Closest I get to cleaning a chain is with more lube and a paper towel. No solvents or brushes needed.
 
At 18k, the back sprocket might still be OK, but the front will likely be showing some wear. Worn sprockets will always decrease the life of a new chain, so yeah, good idea for new, front to back when it's time.
 
 

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