Excessive new chain stretch?

While reassembling my '81 KZ1000 I picked up a new chain from the dealer. After about 1000 miles I had to tighten it up by about one set of marks to bring it back to about 3/4" play. This seemed normal, as I would expect a new chain to stretch a bit as it breaks in.

I'm approaching 2000 miles on the bike now, and today I rode it across town. On the way back home I kept hearing a metal-on-metal tapping so I took a look when I got home. Holy hell the chain is so loose it was smacking the frame!!! The rear axle is still in the position I set it at so that hasn't moved, so I'm guessing the chain must have had some sudden and very extreme wear on it? I'm going to check it over better tomorrow, but wanted to ask if anyone has seen anything like this before. As loose as it is I might have to figure out if this chain will allow me to remove a link, because I'm currently only two marks from the back of the range and I'm pretty sure I'll have to go all the way back to take up that much slack.

I know this sort of thing is hard to diagnose from just a text description, but just wondering if anyone has seen something similar or if it might be an indication of some other problem that I should look for? This was supposed to be the better quality chain, I thought, but there's just no way it should be stretching like this. ON my previous bike I didn't even know I was supposed to leave some slack in the chain and would just pull the rear wheel tight by hand, and I still never had to replace the chain, so something has to be wrong here.

Is it 630 chain? I installed a new chain and sprockets on my Z1B in 2014. I have about 7,000 miles on it and have yet to adjust the chain. Ditto for my KZ1000 with about 7,000 km on it since 2015. Both chains are 630 o ring.

If your chain is stretching that quickly I would think you have an alignment problem or a poorly made chain. I would not suggest removing a link and continuing to use the chain unless you want to wear your sprockets out. There is a spec in the Kaw book...I've forgotten the specifics but I think anything over about 2% elongation is the limit.

Did you change chain and sprockets at the same time? New chains dont last long on old (er) sprockets. Always change chain and sprockets as a set.

^ Yup. That. ^

Shdwdrgn wrote: "While reassembling my '81 KZ1000..."

We can infer from that quote that disassembly has been done. Are the right spacers in the correct positions? Both sprockets should be in the same plane.


Good Ridin'
slmjim & Z1BEBE

A non O ring chain will"stretch" much faster than a O ring chain. What brand it it?
Steve

Warren3200gt wrote: Did you change chain and sprockets at the same time? New chains don't last long on old (er) sprockets. Always change chain and sprockets as a set.

Exactly. If you put a new chain on without installing new sprockets the chain will wear prematurely. Likewise, if you install new sprockets with an old chain the sprockets will wear prematurely. What brand chain did you use, and is it an O-ring or X-ring chain? A cheap chain will wear out quickly. It sounds like you leave enough slack in the chain; what do you use to lube it?

It sounds like your chain is wearing at a very rapid rate. I replaced my original chain with a Tsubaki O-ring chain more than 25,000 miles (12 years) ago and also installed new stock sprockets at that time. I lube it using Maxima Chain Wax every 300-500 miles and wipe off any excess lube. I keep the appropriate amount of slack in the chain. So far, I have only adjusted the chain a bit less than 1/4 inch, so I know it will last a very long time. Ed

SWest wrote: A non O ring chain will"stretch" much faster than a O ring chain. What brand it it? Steve

Good point. I replaced my OEM chain last fall with the closest equivalent riveted EK 630 chain, and new sprockets I could source. I have about 2-3K miles on the new chain and aftermarket sprockets, and have as yet needed to adjust the chain to take up excessive slack. I also repack the sprocket bearing whenever I mess with the rear wheel. I actually remove it, clean it out, then repack it like I would an automotive wheel bearing.

Perhaps the sprocket bearing has left the area?

I bought aftermarket sprockets, against better judgement, but they seem to be ok so far.


I shopped around a LOT before I bought this chain. My dealer had some really CHEAP chain that they wanted 3 times more than I paid for this high quality OEM type o-ring chain. Special note.. be careful counting those chain links. I counted mine 3 times, and the old chain / sprockets were binding up so bad that I could not turn the rear wheel smooth enough that I kept losing count and ended up ordering in the wrong chain (too short) by 2 links. I even marked the starting and end points and STILL screwed up the counts. Every time I had to grunt turning that rear wheel, I must have started back to counting 2 links from where I ended at. <sigh>


AND I bought the elcheapo chain riveter that needed only a little bit of practice and ANOTHER EK master link after screwing up the original one.


Riveting the chain definitely took another try to get it right.

I would say your chain is a low quality one like a Volar chain. Those tend to last about 5000 miles. I've put new quality o-ring chains on old sprockets for decades and not have any high wear issues. Yes in a perfect world you should replace the chain and sprockets at the same time but it won't cause any noticeable excessive wear.

Thanks for all the replies, sorry I missed the email notification or I would have got back sooner...

So first off, this morning I took up the slack in the chain, and for some reason it tightened up MUCH faster than I expected. Like I only had to go a little under 1/2 mark to get it back in spec again. Glad it wasn't that far out, so I'm still 1.5 marks from the last one. I just don't get how it was loose enough to hit the swing arm, yet tightened up again so fast. But it's running smoothly now. I never got around to picking up some chain lube but I brushed on some 80-weight gear oil which seemed to work well. I just got back from riding for a couple hours and didn't have any further problems with the tension.

So yes, you folks are quite right that I made the mistake of replacing the chain (yes it is the original 630 size) without replacing the sprockets. Good advice, and in fact I think I want to go with a smaller rear or larger front sprocket because most of my riding is on the highway and she's running about 4000rpm at 60mph, so I'd like to bring that down a bit more. Our interstates here are 75mph so riding for a couple hours at that speed does seem to warm up the engine. Any suggestions on number of teeth for good highway gears on this bike? Or a rough idea what difference in RPM I might see for each tooth I drop on the rear? I think I'd like to get closer to 4000rpm at 75mph just to bring it down a bit. I will also need to count the existing teeth to see where I'm at, because I had two sets of sprockets, all of which had different tooth counts.

I thought I still had the box the chain came in, but it looks like I tossed it. All I can say is it was a yellow box with black and red print, not sure if that really helps. I would assume this is an O-ring style chain, there is nothing X-shaped about the linkage. This one had a clip on it rather than rivets. I did take care on reassembling the rear wheel to get the spacers back in the right place and the sprockets visually aligned, and there is no side wear that I can see on the rear sprocket although I do think I see some wear down within the teeth (which of course matches what was said about not replacing the sprockets with the chain). All of the wheel bearing were also replaced as the old ones had several years exposer to dirt before being put back on the bike.

So yeah, Winter project looks like new chain and sprockets, plus I need to replace the seals in the front forks since they've been leaking all Summer. And I need to pull the top of the engine to figure out why it sounds like timing chain is hitting the inside of the case. Otherwise it has been running really great this season and I'm sad to see the weather turning chilly already.

An o-ring chain is pretty easy to identify. There is an obvious gap between the outside plates on the links. The o-rings are meant to hold the lubricant grease inside the pin and bushing surfaces.



I just replaced my sprockets with the same 15 / 39 that were on it. While gearing it up a bit, lowering the final gear ratio will also effect low speed operation / torque Just like everything you change, has effects on other things.

Moving the adjustment 1/2 of a mark is a lot. My chain tightens in only a 1/4 -1/2 turn on the adjustment bolt, not the adjustment marks themselves. Hopefully you took a look at the sprocket and swing arm bearings for wear / slop. (Sorry, I did not take any pics of the numerous times I had it apart)I am thinking as much as this chain needs adjustment, there is definitely something wrong. I can't even imagine a really cheap chain stretching this fast., unless it goes on a combine.. and even then..

Wheel bearings are not the same as sprocket bearings. There is a separate bearing on the sprocket assembly with a rubber damper between the sprocket and the wheel. I tried googling it so I could illustrate the bearing, but was mainly seeing a lot of video's with very little illustration value, and a whole lotta obnoxious thumping, overbearing music.. kinda like going to a car wash or gas station in St. Louis city.

The only difference between an X ring and an O ring chain is the cross-section shape of the rings. It is not visible once the chain is assembled.

The sprocket carrier bearing is number 601 in the diagram.
www.partzilla.com/catalog/kawasaki/motor...rear-wheel-hub-chain

I'm running 16/35. I bought a 15 (stock) and ran it for a while. It was fun off the line but 5000 RPM at 70 was too buzzy for me. With the 16 I'm at 4500 @ 70-75. I ran a standard chain after I bought a CHINESE JUNK O ring chain on eBay. Damn near killed me. The standard chain had to be adjusted every 2-400 miles. I wound up buying all new chain and sprockets. The new O ring chain started coming apart at the master link because the lube went away (clip style). The rest of the chain was fine. I got a new O ring chain and front sprocket and it's doing fine. I'll be buying a all new setup soon and start over.
You get what you pay for or like Carl said, "You want cheap, you get cheap".
Steve
kzrider.com/forum/5-chassis/596545-chine...hain?start=40#656870

kzrider.com/forum/5-chassis/597172-chain-recommendation#661586