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Discussion Starter · #1 ·
So I just now needed to tighten my chain, and I though what better time to try out my new bike stand than now!

So after adjusting it to the freeplay specified in the service manual, I then did as I always do. Smash the bike down on the rear suspension, rotate the tire around a few times, and check it again with me sitting on it to ensure it's not too tight. All checked out fine.

Today riding in to school, there was a weird vibration and thrum sound on deceleration. Shifting was EXTREMELY smooth. When I got to school ~24 miles later, I checked the chain tightness while the bike was sitting on the side stand. It was VERY tight, with very little play.

So just a word of warning to those doing their first chain adjustment. Go a tad on the loose side, and if possible, ride the bike for a few and check it again. Be ready to make another adjustment. And if you feel a vibration or hear a "thrumming" sound on clutch-in deceleration, YOUR CHAIN IS TOO TIGHT! Loosen it up before you hit a big bump and break it, or make your output shaft leak!:D
 

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Did you check for the tightest spot before you set the tension?

All chains and sprockets will have some variation and run-out. You have to find the tightest spot first, then set the slack.

Better too loose than too tight - within reason.


Jay
 

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My chain was tight from the factory and the dealer did not notice this at the 600 mile service. It is very important to rotate the back wheel when checking the chain tension and find the tightest spot because, as jkv357 mentioned, there is often a lot of variation. My Honda mechanic suggested I set the chain slack at one inch at the tightest spot. So my slack now varies between 1 and 2 inches so it is within the required limits.
 

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mine was loose from the factory..tightened it at 500 miles to around the minimum spec...in 5,500 additional miles since, it measures at 1"..hardly moved /stretched at all

I dont know why but i dont get and never have had any variance at all..measures the same all the way around chain...every time
 

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Mine got real loose around 7-800 miles too and I set it at 1". Mine also was identical at about 6 or 7 different spots that I measured.
 

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Discussion Starter · #8 ·
Yep. Mine is identical all the way around. If you have run out, either your sprocket is bent, or you don't have all the tension relieved from the drivetrain. In other words, when driving the bike forward, the tension will usually be highest on the top of the chain due to the forward pull. When in reverse, the tightest tension will be on the bottom. As long as the bike is in a neutral position, there should be no variation in tension when spinning the rear wheel. If any of you have that, check your wheel alignment and sprocket alignment. Either may be bent.

Mine didn't really need an adjustment, it was just a little loose for my taste. Then I ended up getting it too tight!:rolleyes: Every bump I hit on the way home made my pucker factor go up.
 

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Yep. Mine is identical all the way around. If you have run out, either your sprocket is bent, or you don't have all the tension relieved from the drivetrain. In other words, when driving the bike forward, the tension will usually be highest on the top of the chain due to the forward pull. When in reverse, the tightest tension will be on the bottom. As long as the bike is in a neutral position, there should be no variation in tension when spinning the rear wheel. If any of you have that, check your wheel alignment and sprocket alignment. Either may be bent.

Mine didn't really need an adjustment, it was just a little loose for my taste. Then I ended up getting it too tight!:rolleyes: Every bump I hit on the way home made my pucker factor go up.
That's not usually true. Almost all chain/sprockets combinations will have some variation that will caused loose/tight spots - even new ones.

If you don't have any variation that's great, but having some amount of tension difference doesn't mean there is a problem.

Even if it's good now, I'd still get in the habit of checking it every time you adjust the chain because it may change as it wears.

I always check the tension in at least 4 spots (valve stem at 12 o'clock, 3 o'clock, 6 o'clock, 9 o'clock) before deciding where to set the tension.


Jay
 

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Discussion Starter · #10 ·
If they have uneven spots that are enough to maltension the chain, then the manufacturing clearances they were made to were very low quality, or they are defective. No point on the chain should ever be tighter than another to any extent that is noticeable if checked at the same spot every time. If so, the chain may have bad clearances between bearings, or one section of chain may be damaged, or the sprockets have uneven teeth. All I know is when we did my buddy's ninja and we swapped his rear sprocket with a cheapo off amazon, it had uneven slop in the chain. Checking with a micrometer, it had run out horizontally and width-wise, albeit just a couple thousandths. Got the official Kawasaki one, and everything is even. No problems since.
 

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Discussion Starter · #13 ·
I just had a flashback from "A Clockwork Orange"...
 
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