Chain adjustment on or off the bike?

[nivram]

Could someone give me a definitive answer on adjusting my chain on a Hyobag I keep reading conflicting information some say adjust the bike with no weight on the bike and others are saying I should adjust sit on the bike and check tension.

If I adjust without sitting on the bike I find the chain is way too tight when I sit on it, any advice?

[FROSTY:Me]

Ive NEVER heard of a bikes chain being tensioned whilst the owner is sitting on the bike.
are you setting the chain at the tightest point ?
Are you setting it to 25mm of slack?

[nivram]

Yeah adjusting at the center of the chain at what would be the tightest point as per manual, I need to have 20-30mm of slack. When I sit on the bike how tight should be chain be should I expect it to be tight with no slack?

[FROSTY:Me]

No the chain shouldn't be tight -I suspect you might not be tensioning it at the tightest spot or another thought is you're rolling the bike back and putting the loose bit at the top run of the chain.

[vifferman]

The chain is usually tightest when the swingarm is directly lines up with the centres of both the front and rear sprockets. You're supposed to set it so the slack is measured when the swingarm is at maximum extension (so the chain has the most freeplay).

[tri boy]

I have found the best way with Hyosung chain adjustment using the following method.
Sit on the bike, and check the freeplay in several spots to make sure the chain isn't worn excessively in a particular area.
Adjust the freeplay, and recheck while sitting on the bike.

Now, here is the trick that works the best.
Lay a shop rag across the lower section of chain, close to the rear sprocket teeth. Wheel the bike forward a wee bit to feed the rag onto the first few teeth.
This quarantees the adjusters are pulled snug to the swingarm ends.
Nip up the axle nut, and nip up the adjusters.
Wheel the bike back, and remove the rag.
Check chain freeplay while sitting on the bike.

This is the best way IMHO.

(There adjusters, and chains are of a lesser quality than most brands).
Almost every one of them that came in for a service had bow string tight chains when the rider was sitting on them.
They spit the clip of the chain joiner frequently if the chain is incorrectly tightened. Use a paint pen to colour the link, and check it before each ride.

[nivram]

Thanks that seemed to do the trick

Just didn't seem right that when I adjusted the chain and sat on the bike that the chain should be so tight that there's was no play just didn't make sense. And I was following Hyosungs adjustment procedure as per there manual which is a worry.

[CookMySock]

I just tension it up and leap on it and see if I can make it go tight at any point. If I make make it bind anywhere, its too tight. At its tightest point (of swingarm movement) it just needs enough slack to not pinch anything. Too loose and its noisy and flappy, and the return links curl up in a nasty scary 'S' at any speed, too tight and it pinches and grinds.

My last chain (hyosung standard chain woefully under-lubed) lasted about 17,000km.

Overall I don't think it matters a shit. As long as its not so tight its making grinding noises, and not so loose it comes off.

Steve

[tri boy]

Tight chains, besides wearing the sprockets and links prematurely, put extra load on the countershaft/out put bearing.
If incorrect adjustment towards being tight continues, early bearing failure is possible. (the stress loads should never be underestimated, especially on engines with light weight bearings).
Worn bearings will then allow for excessive loading on engaging drive gears, causing hardfacing to fail early.
It's the start of a very slippery slope towards gearbox failure.

[Taz]

Trail bike chains are best checked by weighting the bike to get the sprocket/swingarm in a straight line as this will be the tightest spot. Not so important on a road bike due to shorter suspension travel but still worth checking in that position. I do this by leaning over the seat pushing down and checking the chain adjustment. None of this applies to the BMW G450 tho.

[rok-the-boat]

You should be able to do it without sitting on it, but, once done, sit on it and make sure the chain has a bit of slack once the swinging arm lines up horizontally with the sprocket. Otherwise, the chain may be too tight. If on doing that, the chain is too loose at rest - without sitting on it, the chain may be stuffed (worn too long). The easiest test for a stuffed chain is to see if a pencil will go between the chain and rear sprocket. If it does, your chain will probably come off itself while riding if you don't change it.

[Ocean1]

First, (like the nice man says) the slack should be checked with enough load on the back to line up the back axle with the swingarm pivot and the countershaft.

Can't be arsed finding a Hyosung pic, but some variation of this will work: Put a phone book on the seat, wrap a cargo strap over the phone book and through the back rim and crank the suspension down until those three points line up, (make sure the bike don't fall off it's side stand here). Check the chain slack half way between the sprockets, 20mm is good. If it's an old chain check it in several places to see if it's worn evenly, if not replace it.

You only need to do this once. When you're finished checking the slack in the "correct" position as above let the strap go, jump around on the bike a bit to "normalise" the suspension and put the bike back on it's stand. Measure the slack again carefully and write it down. Whatever it measures is your new reference, from now on you set the slack to that measurement with the bike on it's stand.