Replaced the o-ring chain on the Enertia with an EK 420-SRO o-ring chain about 1000 or so miles ago due to the old chain making a clicking noise at each rotation. It was also fairly rusted. From what I've read it's best to replace the sprockets at the same time, but I don't believe that there are any new sprockets available for the Enertia. If someone has found a substitute that works please let me know.
The Enertia manual states that when the bike is on its side stand, the slack measured at the mid point between the front and rear sprockets should be between 1 inch and 1 3/8 inches. From my experiences, I feel that anything less than 1 3/8 inches of slack makes the chain far too tight when sitting on the bike. There is very little vertical movement. Does anyone else have any experiences to share on this?
I've adjusted and lubricated the chain several times since it was installed because it either seemed too loose or too tight. The strange thing is that even though the chain has most likely worn since installation, after tightening the adjusters on the swingarm, the distance from the axle block to the rear of the swingarm change is less that a millimeter. I've also noticed that while riding the bike feels like there's additional resistance when the chain has less than 1 3/8 inches of slack in it.
Also, I took a close look at the sprocket teeth and it looks to me like there's some uneven wear. The best way I can describe it is that some teeth appear to be more narrow than others. It's difficult to see in the photos, but it looks like the teeth go thick, thin, thick, thin etc. I've included a photo that will hopefully help.
I'm also wondering if the chain itself is wearing unevenly. I took measurements with the bike on its side stand at 7 different points roughly 12 inches apart. Here are the slack measurements:
1. 1 3/8"
2. 1 1/4"
3. 1 1/8"
4. 1 3/8"
5. 1 1/4"
6. 1 3/16"
7. 1 1/16"
From what I've read a chain that is too tight will cause accelerated sprocket wear, so I'd rather have the chain to be a little on the loose side. I'm planning on adjusting the tension again because as I mentioned before, anything less than 1 3/8" seems to be too tight. I thought that the last time I adjusted the chain it was close to having 1 3/8 inches of slack at the tightest point on the chain, but I must have made a mistake because now the chain has more tension than it did after the last adjustment. Very frustrating to say the least.
Sorry for the long post. Hoping someone has some chain wisdom to share. Thanks!