Author Topic: Sprocket bolts snapping off - Removing Bearing Retainer???  (Read 7369 times)

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Offline brycegp

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Sprocket bolts snapping off - Removing Bearing Retainer???
« on: July 12, 2010, 08:42:03 AM »
So I was riding home yesterday....50 mile ride.  And every sharp left turn i would hear a "tick tick tick"...then I would lean back to see/hear the issue and nothing.  I pulled over and the chain looked a little dry so I thought maybe it was making noise cuz it needed oiled.  Found an auto parts store around the block...oiled the chain.

But sure enough, the next sharp left turn I heard it again.  And this time when I looked back at the rear tire (sprocket side) I see a piece of metal fly off.  So I immediately pull over and inspect.  but the wheel still was spinning smoothly.  finally i realize that three of the four sprocket bolts are missing.

somehow the sprocket bolts were hitting the swing arm when I took a sharp left turn.  And it was clipping them off.  But since it was only in a sharp turn, when I inspected it upright it was fine.  

I know how to fix it.  And I need a new cush drive.   >:(  

but anyone had this issue before??

« Last Edit: August 01, 2010, 08:58:07 AM by brycegp »
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Offline CycleRanger

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Re: Sprocket bolts snapping off...
« Reply #1 on: July 12, 2010, 08:45:26 AM »
Allow me to be the first:   What bike?  ;)
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Offline fire113

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Re: Sprocket bolts snapping off...
« Reply #2 on: July 12, 2010, 09:21:58 AM »
Allow me to be the first:   What bike?  ;)

1+ ^^


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Offline brycegp

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Re: Sprocket bolts snapping off...
« Reply #3 on: July 12, 2010, 01:12:44 PM »
Sorry...

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Offline brycegp

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Re: Sprocket bolts snapping off...
« Reply #4 on: July 13, 2010, 12:07:05 PM »
Nothing, guys?  Thought you guys would have some input on this....

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Offline turboguzzi

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Re: Sprocket bolts snapping off...
« Reply #5 on: July 13, 2010, 12:13:56 PM »
the NUTS, not bolts in a stock 500 hub should have bendable long washers underneath, they are there exactly to prevent this very dangerous situation. could end in tears. if you omitted them while fitting your rear sprocket slap your own hands, if its the PO, then find him and kill him... ;)

TG

Offline CycleRanger

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Re: Sprocket bolts snapping off...
« Reply #6 on: July 13, 2010, 12:53:30 PM »
the NUTS, not bolts in a stock 500 hub should have bendable long washers underneath, they are there exactly to prevent this very dangerous situation. could end in tears. if you omitted them while fitting your rear sprocket slap your own hands, if its the PO, then find him and kill him... ;)

TG

Example of what sprocket lock washers might look like.
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Offline brycegp

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Re: Sprocket bolts snapping off...
« Reply #7 on: July 13, 2010, 01:23:21 PM »
the nuts and studs (BOTH) were clipped off by hitting the swingarm...and them coming loose doesn't seem to be the problem.  the lock washers WERE on there.  the one NUT AND STUD that is still on there...still has the lock washer on there.

the problem is that they got clipped off by smacking the swingarm when I leaned into a LEFT TURN.  So the wheel must be flexing when leaning into a turn.  Can a bad rear wheel bearing allow the rear wheel to flex off center in a turn or something?

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eurotrash

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Re: Sprocket bolts snapping off...
« Reply #8 on: July 13, 2010, 01:27:36 PM »
Guys, so to be clear here, the hub uses studs/nuts to retain the sprocket... aided by lock washers that Cycleranger was good enough to show.

I think what Bryce is trying to express is that it seems his hub is somehow leaning into the swing arm while turning left..  I don't think bad wheel bearings cause this?!  Seems like they would have to be pretty toasty and generating serious noise before getting to that point.  And knowing Bryce, he'd have noticed that weeks ago.

So where, aside from the attaching point, could the wheel/hub assembly possibly give enough to allow the sprocket to lean into the swing arm?!
« Last Edit: July 13, 2010, 01:32:49 PM by eurotrash »

Offline lone*X

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Re: Sprocket bolts snapping off...
« Reply #9 on: July 13, 2010, 01:29:45 PM »
Axle nut properly torqued?  Wheel properly aligned with the bike?  Bad swing arm bushings?

« Last Edit: July 13, 2010, 01:35:40 PM by lone*X »
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Offline brycegp

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Re: Sprocket bolts snapping off...
« Reply #10 on: July 13, 2010, 01:55:58 PM »
pic one of the missing nuts and studs...

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Offline xenoscr

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Re: Sprocket bolts snapping off...
« Reply #11 on: July 13, 2010, 02:02:57 PM »
Do you have a pic of the whole swing arm that shows the spacing between the swingarm and sprocket? If you lift the bike onto the center stand, how much play is in the wheel? If there is noticeable play, can you visually see where?

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Offline Frostyboy

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Re: Sprocket bolts snapping off...
« Reply #12 on: July 14, 2010, 03:55:04 AM »
Now I'm only guessing that the rear hub is the same as a 550, but what if the rear wheel bearing retainer nut has loosened or come off? It's hidden behind the plate over the sprocket & the final drive flange could move outwards, away from the hub & possibly allow the sprocket studs to strike the swing arm. If the bearing is still being held in the hub by the spacers & the axle nut is secure, the drive flange could still be on the loose. Why it only happens when turning left, I can't imagine. Maybe gravity?
See if the final drive flange can be moved away from the hub & that should hopefully reveal the problem.
Just my .02 cw.
« Last Edit: July 14, 2010, 03:59:48 AM by Frostyboy »
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Offline turboguzzi

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Re: Sprocket bolts snapping off...
« Reply #13 on: July 14, 2010, 04:11:41 AM »
if everything is left stock, the left wheel spacer presses on the bearing and the bearing presses on the cush drive, so even without the spring clip, the cush part cant move sideways. the wheel would have to be impossibly miss-aligned for the studs/nuts to touch the swingarm.

something is wrong big time....

better pics will help us understand what

TG

Offline lone*X

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Re: Sprocket bolts snapping off...
« Reply #14 on: July 14, 2010, 11:45:48 AM »
Could it be that the left wheel spacer was not installed?
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Offline brycegp

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Re: Sprocket bolts snapping off...
« Reply #15 on: July 14, 2010, 02:57:28 PM »
Thanks for all the suggestions for what to look for, guys!

I'm waiting on my new cush drive and wheel bearings to show up and then I disassemble it find out what is causing the problem.

I get picks up when I disassemble it....
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Offline brycegp

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Re: Sprocket bolts snapping off...
« Reply #16 on: July 17, 2010, 02:33:07 PM »
New, used cush drive showed up today.

Before:


Shortly after:


Just waiting on my new wheel bearings and I'll get it swapped out.
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Offline brycegp

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Re: Sprocket bolts snapping off - w/ pix b4 I fix
« Reply #17 on: July 17, 2010, 02:50:06 PM »
Keep in mind fellas, I rode this bike EVERYDAY for the past 2 years...so this isn't an install issue.  Unless the PO did it wrong and it just cause a problem 2 years later.

Here are pics of the rear before I take it apart...

1.


2.


3.


4.


5.
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Offline dave500

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Re: Sprocket bolts snapping off - w/ pix b4 I fix
« Reply #18 on: July 18, 2010, 04:27:44 AM »
is the chain one link too short and its all too far forward?

Offline Frostyboy

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Re: Sprocket bolts snapping off - w/ pix b4 I fix
« Reply #19 on: July 18, 2010, 05:24:13 AM »
What strikes me as odd is the amount of thread that is exposed on the studs compared to my rear wheel. There is 1½ threads max outside the nuts on my flange. There looks to be about 4 times that on your pic.
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Offline CB500_k2

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Re: Sprocket bolts snapping off - w/ pix b4 I fix
« Reply #20 on: July 18, 2010, 05:32:47 AM »
Here is a picture of my rear sprocket (CB500)  You will notice that end of the securing bolts does not go beyond the rim of the chain retaining ring.  On your pictures the remaining  bolt extends way beyond the ring.  This suggests that there may be a problem in the wheel hub, possibly the cush drive.
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Offline brycegp

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Re: Sprocket bolts snapping off - w/ pix b4 I fix
« Reply #21 on: July 18, 2010, 12:33:35 PM »
What strikes me as odd is the amount of thread that is exposed on the studs compared to my rear wheel. There is 1½ threads max outside the nuts on my flange. There looks to be about 4 times that on your pic.

After inspecting a friends cb500, i noticed this as well...  it is definitely at least part of the problem.

Like I said, I've been riding this for 2 years.  And it only recently became an issue.

Is it possible that the stud has been vibrating/turning...and working its way out...while the nuts because it is locked stays where it is??
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Offline brycegp

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Re: Sprocket bolts snapping off - w/ pix b4 I fix
« Reply #22 on: July 18, 2010, 12:46:52 PM »
Here is a picture of my rear sprocket (CB500)  You will notice that end of the securing bolts does not go beyond the rim of the chain retaining ring.  On your pictures the remaining  bolt extends way beyond the ring.  This suggests that there may be a problem in the wheel hub, possibly the cush drive.

I've had to replace the cush drive...and I will make sure that the studs are not extending so far outward this time around.  In addition, I am replacing the wheel bearing just in case there is an issue there.

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Offline andy750

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Re: Sprocket bolts snapping off - w/ pix b4 I fix
« Reply #23 on: July 18, 2010, 01:33:49 PM »
Curious question but shouldnt the axle nut be on the other side (right hand side)? I have no experience with 550s but on all the 750s I have seen its been on the right.

Andy
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Offline IndyFour

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Re: Sprocket bolts snapping off - w/ pix b4 I fix
« Reply #24 on: July 18, 2010, 01:51:00 PM »
Curious question but shouldnt the axle nut be on the other side (right hand side)? I have no experience with 550s but on all the 750s I have seen its been on the right.

Andy


The axle nut is on the left (chain side) on the 500/550.  I never realized that it was different for the 750 until you asked that.   :)
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Offline brycegp

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Re: Sprocket bolts snapping off...
« Reply #25 on: July 18, 2010, 01:57:51 PM »
the NUTS, not bolts in a stock 500 hub should have bendable long washers underneath, they are there exactly to prevent this very dangerous situation. could end in tears. if you omitted them while fitting your rear sprocket slap your own hands, if its the PO, then find him and kill him... ;)

TG

Example of what sprocket lock washers might look like.


Anyone got a spare sprocket lock washer.  Mine is shot now.  >:(
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Offline IndyFour

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Re: Sprocket bolts snapping off - w/ pix b4 I fix
« Reply #26 on: July 18, 2010, 01:59:58 PM »
Looking at Frostyboy's exploded diagram above....could it be that the threaded studs (part #19) that go into the cush drive are longer on one end than the other....and that they were put in backwards, causing them to stick out past the nuts?  I've had my back axle apart to replace bearings, but I never removed these studs to know if they are the same length (thread-wise) on both ends.  Just a thought.
« Last Edit: July 18, 2010, 02:01:32 PM by IndyFour »
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Offline Frostyboy

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Re: Sprocket bolts snapping off - w/ pix b4 I fix
« Reply #27 on: July 18, 2010, 04:28:26 PM »
Is it possible that the stud has been vibrating/turning...and working its way out...while the nuts because it is locked stays where it is??
I wouldn't think so, at least not for all 4 to loosen off simultaneously.

Curious question but shouldnt the axle nut be on the other side (right hand side)? I have no experience with 550s but on all the 750s I have seen its been on the right.

Andy


The axle nut is on the left (chain side) on the 500/550.  I never realized that it was different for the 750 until you asked that.   :)

Mine was originally on the L/H/S, but I changed it to the R/H/S so I didn't have to remove the muffler when I wanted to remove the rear wheel. It doesn't appear to have made any difference.
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Offline turboguzzi

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Re: Sprocket bolts snapping off - w/ pix b4 I fix
« Reply #28 on: July 19, 2010, 04:30:05 AM »
studs should definitely be almost flush with the nut's top surf. if not, they've been put the other way around.

TG

Offline Frostyboy

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Re: Sprocket bolts snapping off - w/ pix b4 I fix
« Reply #29 on: July 19, 2010, 05:14:04 AM »
I'm puzzled here again. I've cropped your pic #1 and then took a pic of my drive flange with the spacer in place.
Is it just me, or does it look like the spacer is missing in your pic or are the tin plates a different shape?
It seems that the whole setup on your machine is a lot closer to the chain adjuster than mine would be if it was mounted.
Maybe someone else can take a pic at the same angle as your #1 & post it.
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Offline brycegp

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Re: Sprocket bolts snapping off - w/ pix b4 I fix
« Reply #30 on: August 01, 2010, 08:57:27 AM »
UPDATE:

I am finally fixing this thing.  After it took FOREVER to get my new Cush Drive and new bearings...and a couple other odds and ends.

This is where I am.  I removed the rear tire...but on the Cb500 there is a retainer ring (screws into the hub) that holds in the bearings.  But more importantly, it holds on the Cush Drive.   I don't have a tool to get it off.  And the installer put it on there GOOD AND TIGHT.

Any suggestions on where to get a tool to remove it??

WIDE of TIRE:


Close up of retainer rings:
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Offline Duke McDukiedook

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Re: Sprocket bolts snapping off - Removing Bearing Retainer???
« Reply #31 on: August 01, 2010, 09:10:55 AM »
You could either buy the custom Honda tool or fab one yourself with bar stock and welding tabs to go in the recesses- people in here have done it before.

Bearing retainer removal page
« Last Edit: August 01, 2010, 09:24:13 AM by Dukiedook »
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Offline SohRon

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Re: Sprocket bolts snapping off - Removing Bearing Retainer???
« Reply #32 on: August 02, 2010, 03:03:38 AM »
I'm puzzled here again. I've cropped your pic #1 and then took a pic of my drive flange with the spacer in place.
Is it just me, or does it look like the spacer is missing in your pic or are the tin plates a different shape?
It seems that the whole setup on your machine is a lot closer to the chain adjuster than mine would be if it was mounted.
Maybe someone else can take a pic at the same angle as your #1 & post it.


Actually, it looks like your spacer might be in backwards, Frosty... the "collar" or "shoulder" fits down on the bearing while the rest of it extends out through the plate. His looks like it's in right, but definitely looks too short. Here are some pics to demonstrate:





« Last Edit: August 02, 2010, 03:15:13 AM by SohRon »
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Offline IndyFour

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Re: Sprocket bolts snapping off - w/ pix b4 I fix
« Reply #33 on: August 02, 2010, 05:46:37 AM »
UPDATE:

I am finally fixing this thing.  After it took FOREVER to get my new Cush Drive and new bearings...and a couple other odds and ends.

This is where I am.  I removed the rear tire...but on the Cb500 there is a retainer ring (screws into the hub) that holds in the bearings.  But more importantly, it holds on the Cush Drive.   I don't have a tool to get it off.  And the installer put it on there GOOD AND TIGHT.

Any suggestions on where to get a tool to remove it??



Here's another thread showing how to get it off.  

http://forums.sohc4.net/index.php?topic=58147.0

Make sure you drill out the stakes first or you will never get it off....even with a special tool.  I used a large flat blade screwdriver and tapped the retainer via the holes to turn the retainer clockwise (it is reverse threaded on the 500/550....in this case righty is NOT tighty...it's loosey).  This was after the stakes were drilled out.  Mine came off fairly easily, but I have heard of people having to use heat to get it loose.
« Last Edit: August 02, 2010, 05:51:12 AM by IndyFour »
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Offline Frostyboy

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Re: Sprocket bolts snapping off - Removing Bearing Retainer???
« Reply #34 on: August 02, 2010, 06:46:03 AM »
Actually, it looks like your spacer might be in backwards, Frosty... the "collar" or "shoulder" fits down on the bearing while the rest of it extends out through the plate.

Doh, thanks for pointing that out SohRon, you're right. It's been that way since I can remember. I must put that right before the wheel goes back on.
Cheers.
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