chilleary Posted November 3, 2015 Share Posted November 3, 2015 I have a 2002 VFR without ABS, it has 60k and I use it daily for commuting to work. About 1,000 miles ago I changed the chain and sprockets. Within about 700 miles I broke the chain while riding home from work. It broke the case cover but with about $50 in parts from eBay I fixed it. The sprockets looked brand new so I bought another o-ring chain and put it on the existing sprockets. Chain broke again within about 700 miles. Not as much damage this time. I bought a new set of sprockets and a new chain and just installed them. My concern is 2-fold: 1) The rear suspension has not been touched since the bike was new. It feels like the bike is sitting "lower" and it "hits hard" over bumps. I am concerned the suspension is so low that the chain slack is being taken up and causing it to break. 2) I thought maybe I installed the front sprocket backwards. When I pulled it apart the spacing on the front and back of the front sprocket is the same (impossible to install it backward from what I can tell). It is a JT and I put the logo facing out (away from the trans). The back sprocket is "indented" meaning it has an undercut section around the ring. The first two times I placed the indent facing out (away from the hub) with the stampings (the part number) also facing out. This time I turned it around and faced the indent "In" toward the hub. The chains are all DID gold chains with O-rings. I have changed chains MANY times before so I don't think I am missing anything in the process. But to be sure I have watched all the YouTube videos I could find just to make sure. Nothing jumped out at me. Has anyone experienced 2 broken chains back-to-back like this before? Anyone have any ideas on what could be causing this? Any help would be appreciated. Link to comment Share on other sites More sharing options...
Member Contributer Rice Posted November 3, 2015 Member Contributer Share Posted November 3, 2015 No experience with broken chain - Thankfully. Only thing that comes to mind, is your chain is too tight. It really doesn't fully explain breakage (IMHO), since you need LOTS of force to brake one of those chains, esp. when they're new. But it's something to check. Link to comment Share on other sites More sharing options...
Member Contributer Marooncobra Posted November 3, 2015 Member Contributer Share Posted November 3, 2015 Where did the chain break? Was it at the link that you joined the chain at? Is it a riveted link type or a removable link type chain? Link to comment Share on other sites More sharing options...
Member Contributer wagzhp Posted November 3, 2015 Member Contributer Share Posted November 3, 2015 No experience with broken chain - Thankfully. Only thing that comes to mind, is your chain is too tight. It really doesn't fully explain breakage (IMHO), since you need LOTS of force to brake one of those chains, esp. when they're new. But it's something to check. Ditto. Regarding the rear sprocket, the flat side of the sprocket should go against the hub, and the concave (indented) side should face outward or to the left side if standing behind the bike. Regarding the suspension, check your sag settings, with you on the bike it should be 30-35mm. The chain slack needs to be measured with the bike on the center stand, and I think the range is .75 - 1.5 inches, and I always err on the loose side. I adjust the slack to where the middle of the bottom run of the chain can be pushed up and easily touch the swing arm. If the chain is too tight the, suspension travel could be putting excessive tension on the chain leading to the failures. [Edited for clarity. Thanks Terry] DID chains are good chains, but the base level model isn't much better than those offered by other manufacturers. You should be using the DID 530 ZVMX chain and matching 530 sprockets. The ZVMX is rated for 1400cc bikes, which is way overkill for a VFR800, but they provide the best longevity. (Using a 520 chain/sprockets is possible, but won't last nearly as long. And since the VFR is a fairly heavy bike, what's the point of the weight savings of a lighter chain?) Link to comment Share on other sites More sharing options...
Member Contributer Terry Posted November 3, 2015 Member Contributer Share Posted November 3, 2015 Assuming your chain did NOT break due to a poorly assembled master link, then the only way to break it would be to have too little slack. When the bike is on the centrestand and the suspension is fully unloaded, the swingarm will hang down a little, making the total chain run shorter and the chain slacker. When you compress the suspension you pass through the point where the front sprocket, rear sprocket and swingarm pivot are all in line, and that is the longest chain run and hence the point the chain is tightest. Once you compress the suspension further beyond this position the chain will start to slacken off again. The chain goes through all of this every time you go over a bump or hit a dip. So I can't see that sag could cause any issues for the chain; sag just determines the bikes attitude.. But if you set the chain with little or no slack when on the centrestand, you will over-stress it when you go over a bump. Link to comment Share on other sites More sharing options...
chilleary Posted November 4, 2015 Author Share Posted November 4, 2015 The link I used on the first chain was a rivet. The second chain had a clip style link, and the one I just put on is a rivet again. I normally use rivets, not clips due to the negative press about the clip coming off. unfortunately both chains let loose while I was at 85mph on the freeway and there was really no safe way for me to recover them so I don't know how or where they broke. I did continually check the clip after installation and it looked perfect every time (no separation, skew or looseness). I remember now that I also replaced the rear brake pads when I changed the first chain. I had to remove the rear axle to get everything off. Is it possible I reassembled the rear axle incorrectly? How would I check? is it possible that a SSSA could not be "aligned" squarely with the rest of the bike? Maybe a worn swing arm bush? thanks for all the input so far. Link to comment Share on other sites More sharing options...
Member Contributer The mailman Posted November 4, 2015 Member Contributer Share Posted November 4, 2015 I remember now that I also replaced the rear brake pads when I changed the first chain. I had to remove the rear axle to get everything off. Is it possible I reassembled the rear axle incorrectly? What? Why would you have to pull the rear axle for the chain OR the brake pads? However, my first guess is your chains were too tight. Link to comment Share on other sites More sharing options...
Member Contributer Cogswell Posted November 4, 2015 Member Contributer Share Posted November 4, 2015 The sprockets would have to be way off to cause a failure - binding and wear would be noticeable. Seems unlikely. You could remove the chain guard and use a straightedge to check. I'm also in the 'chain was probably too tight' camp. Link to comment Share on other sites More sharing options...
Member Contributer Marooncobra Posted November 4, 2015 Member Contributer Share Posted November 4, 2015 I suggest that the chain was too loose. A chain that is too loose will wear quickly and may have a whip action that can cause it to snap. A drive chain that is too tight speeds up wear by excessive pressure on the sprocket teeth, the chain joints and the shaft bearings. A chain that is too tight or too loose will result in excessive elongation. Missalingment of the sprockets increases drive noise levels and increases chain and sprocket wear. Chains operating on missaligned sprockets have a tendency to develop tight links/joints because sprocket teeth force the inside plates outwards on the bushing, thus binding the joint. Link to comment Share on other sites More sharing options...
Member Contributer VFROZ Posted November 4, 2015 Member Contributer Share Posted November 4, 2015 My guess is with too tight. When the bike is on the centre stand, the chain is lose, as the swing arm travels through its arc, the chain tightens, as it keeps travelling up, it loosens again. If you don't have enough free play, it will pull too tight as it gets past mid way point. A big bump could have enough inertia to snap your chain (a cheap one). You do not remove anything to replace rear pads, I suggest you download the manual and read it, including the section on chain adjustment. Link to comment Share on other sites More sharing options...
V4 Rosso Posted November 4, 2015 Share Posted November 4, 2015 I have changed chains MANY times before so I don't think I am missing anything in the process.Do you use a torque wrench to tighten the clamping bolt on the back of the swingarm? Maybe it is broken and when the bearing carrier is not clamped down enough it will rotate and on the 5th gen and above will take the slack out of the chain. On the 3rd and 4th gen the chain will become loose. Link to comment Share on other sites More sharing options...
Member Contributer Switchblade Posted November 4, 2015 Member Contributer Share Posted November 4, 2015 For sure you have been lucky two times , I would check chain alignment between the sprockets and look at the rear for odd tilt to the sprocket. Can you post some closeup pic's of the chain links? Link to comment Share on other sites More sharing options...
checksix Posted November 4, 2015 Share Posted November 4, 2015 My vote is a problem with the clamping bolt and/or eccentric rear axle bearing installation, causing the axle bearing to gradually rotate and tighten the chain as you ride. I think I recall reading that the bearing can be rotated too far during installation, causing the chain to tighten rather than loosen as the bearing is rotated. Maybe someone more knowledgeable than me can comment on this. edit: "rear hub" --> "rear axle bearing" Link to comment Share on other sites More sharing options...
chilleary Posted November 13, 2015 Author Share Posted November 13, 2015 Thanks for the feedback guys. I need to go back to understand why I felt I had to remove the rear axle to change the rear pads. Honestly, I don't remember why. It made sense at the time and it worked. Anyway, my chain problem appears to be gone after I installed new sprockets and a new chain. In hind sight I think the rear sprocket was the problem. I know you all think I had the chain too tight. I have changed A LOT OF CHAINS over the years and I am very sure it was not too tight, certainly not twice. But I certainly appreciate your input on this as I know a tight chain will break quick. When I first swapped out the sprockets and chain the new rear sprocket "didn't fit quite right". It didn't slip over the rear hub smoothly, I had to apply some pressure to get it to seat. The bolts also didn't go through the holes properly. A few of them I could just barely get through the sprocket holes, I started the but, then cranked on the nut to "pull" the bolt through the hole the rest of the way. After I had everything installed I spun the wheel, everything looked good. I could see that the sprocket was seated against the hub well and in my mind chalked up the rough installation to a poorly machined rear sprocket. I think that rear sprocket was the issue. I think it was not machined correctly and the way it went onto the bike was an indication that other parts of it were probably also not machined right. Or if it was a casting it was not plated correctly (it was chrome plated). Going forward I will be much more wary of any sprocket that does not go in smoothly and bolt up easily. It drives me crazy when people don't come back and close their posts and let us know how they finally resolved their problems so this is what I am attempting to do here. Thanks again for everyone responding. Keep the rubber-side down. Link to comment Share on other sites More sharing options...
Member Contributer Rectaltronics Posted November 13, 2015 Member Contributer Share Posted November 13, 2015 Lack of resolution posts make me nuts too. Thanks for the follow-through!!! And glad you have it all working OK now. Link to comment Share on other sites More sharing options...
Roebling3 Posted November 13, 2015 Share Posted November 13, 2015 BTW: Small laser beam measuring devices cast a nice bright red narrow beam that's great for checking alignment sprocket to sprocket, etc. R3~ Link to comment Share on other sites More sharing options...
Member Contributer Switchblade Posted November 13, 2015 Member Contributer Share Posted November 13, 2015 BTW: Small laser beam measuring devices cast a nice bright red narrow beam that's great for checking alignment sprocket to sprocket, etc. R3~ Amen ! Link to comment Share on other sites More sharing options...
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