Drive Chain Slack

[Anonymous]

Every time I set my chain tension to about 1" it goes back to a bit over 2" after a little riding. Do chains tend to stretch to a position that they feel comfortable at or someting? The axle isn't moving to where it was previously as far as I can tell. I've been setting the chain to about 1" because it seems right and I have gotten conflicting values for the slack.

Thanks, Steve

[earlfor]

Re: Drive Chain Slack

THERE! You have hit it exactly. Chains DO "relax" at a position they feel "comfortable" at. Different types and makes, will naturally assume a different running tension. If set too tight, it will stretch until it reaches it. I usually set the chain at about 1 1/4" to 1 1/2 slack. After setting a chain, it will usually stretch to its
"preferred" tension in about 150 miles. Note the slack at that point and thereafter, set it to that amount. You will find that you
subsquently will need to make very few adjustments to your chain tension. Set up this way, I tighten my chain about 1/4 turn on the adjuster bolt every 3 or 4 hundred miles. Ya gotta keep the chain slippery lubed too, otherwise beat build up will make it stretch.
If your rear rim stays shiny, youre not using enough lube. :-)

Earl

Every time I set my chain tension to about 1" it goes back to a bit over 2" after a little riding. Do chains tend to stretch to a position that they feel comfortable at or someting? The axle isn't moving to where it was previously as far as I can tell. I've been setting the chain to about 1" because it seems right and I have gotten conflicting values for the slack.

Thanks, Steve

[Anonymous]

If your rear rim stays shiny, youre not using enough lube.

Earl

i oil my chain thoroughly every couple of hundred miles with a 50/50 mix of 10w/50 and stp and i give it a shot just about every time i ride.. my rear rim is always awfull looking and i dont want to use any wax or whatever- my spockets show almost no sign of wear and the chain seldom requires adjusting--- But then i am not a bike polisher and dont mind a leak here or there

[crc1214]

A post brought back from the dead!!!

Did some searching and ran across it.

The exact same thing is happening with my brand new x-ring chain and sprockets.

When cold, I have MAYBE 1/2 of slack, more like 1/4"!!! That's because when I ride I get tired of the damned thing stretching to about 1" of slack. When it gets warm like that, I can feel it flopping when I decelerate!!!!!!

I'm driving myself nutty!!!!! If I set the chain slack at around 1" from the get-go, it will stretch to about 2" when it warms up - WAY to much slack!!!!

And the weird thing is this......... when I let the chain cool down some, and check the slack again, it will be at it's original setting!!!! This is driving me NUTS!!!!

Example........ I'll check the slack before riding......... 1/2". Start riding, pull off after about 15 minutes........ slack is a little over 1". Go back home, let the chain cool off, and check the slack....... back to 1/2". I WANT TO RIDE WITH 1/2" of slack all the time. It gives me smoother shifting and the chain doesn't flop around. But, this requires having a COLD chain slack of hardly 1/4"!!!!!!!!! What do I do?????

Chad
Columbus, OH 1978 GS550E

[crc1214]

A post brought back from the dead!!!

Did some searching and ran across it.

The exact same thing is happening with my brand new x-ring chain and sprockets.

When cold, I have MAYBE 1/2 of slack, more like 1/4"!!! That's because when I ride I get tired of the damned thing stretching to about 1" of slack. When it gets warm like that, I can feel it flopping when I decelerate!!!!!!

I'm driving myself nutty!!!!! If I set the chain slack at around 1" from the get-go, it will stretch to about 2" when it warms up - WAY to much slack!!!!

And the weird thing is this......... when I let the chain cool down some, and check the slack again, it will be at it's original setting!!!! This is driving me NUTS!!!!

Example........ I'll check the slack before riding......... 1/2". Start riding, pull off after about 15 minutes........ slack is a little over 1". Go back home, let the chain cool off, and check the slack....... back to 1/2". I WANT TO RIDE WITH 1/2" of slack all the time. It gives me smoother shifting and the chain doesn't flop around. But, this requires having a COLD chain slack of hardly 1/4"!!!!!!!!! What do I do?????

Chad
Columbus, OH 1978 GS550E

[Jethro]

I leave my chain slack at about 1 1/2" cold. It doesn't seem to change much if at all when it warms up.

For lubrication I remove the chain about twice a year (more if I ride a lot) and clean it with kerosene and then heat it up with a heat gun and coat with 90wt gear oil. I wipe off the excess and mount it the next day. This was advice a racer friend gave me.

[Anonymous]

Be aware that when setting the chain slack, the bike trailing arm moves in an arc, and the tightest point is when the rear axel is in the same horizontal plane as the motor sprocket.

I believe stock setting deflection at the chain center point between the two sprockets.

Using 1 inch and making sure the bike is as close to "neutral" position for the trailing arm will probably work and compromise between the aggravation chain slack mentioned and the constant chain stretching if using 5/8.

Lastly, if the chain is not quite new or all parts not quite new, rotate the chain and check for tight spots in the rotation. While this is not a desired condition, it does in fact happen-particularly during readjustment of a chain. - TDieter

[crc1214]

Thanks for your replies guys. Jethro, at 1 1/2" slack you aren't getting any whipping, especially on deceleration? WOW!

What size are your sprockets?

I'm thinking the unusually high final gear ratio of my 550 probably doesn't help matters much. Any oscillation of the chain is magnified greatly.

I have a 50T rear and 15T front!!! Maybe the Suzuki engineers learned their lesson after trying this freakishly high combination, and that's why most sportbikes today are more like 43T rear and 15T front!!!

Just a thought.

Anyhow, I'm going out for a short ride today and will set my slack to about 1" before riding (cold), and I'll see if it helps.

I'll let you guys know.

[Jethro]

No, I don't seem to have any problems with whipping or anything. It shifts nice and smooth too. The bike has been converted to a 520 chain and sprockets. I believe they are 15-48?? Not quite sure, I'll have to check today.

[focus frenzy]

first things first, lets get it out of the way as it is expected from me.
SHAFTIES RULE!!!

next you need to set your preload to the lowest level and compress you suspension to where the swing arm and the rear axle is perfectly in line with the counter shaft. you set you slack at this point, way back when i was crippled with a drive chain (before I saw the light ) I would set just a hair bit of slack with the suspension compressed down to this level, this is the tightest point.
if you set your slack with the bike on the side or center stand, it is going to be to tight and when the suspension compresses it will stretch the chain shortening it's life.
a couple dirt bikes with long suspension travel use a idler sprocket to take up slack.

[focus frenzy]

I would like to add, you can use a ratchet strap looped over the seat or better yet, the sub frame under the seat and hooked to ether side of the swing arm to compress the suspension and hold it compressed while you adjust it.

[saaz]

I have always found that you need to find the tight spot in the chain, then check for the correct tension with normal riding weight on the bike. Once you have that, see what the tension is set at when the bike is on the centre stand. Use that setting for regular checking.

[crc1214]

Well, I'll tell you what. This whole thing is driving me nutty.

First, let me say this........ SHAFTIES DO RULE!!! I had the pleasure of riding my buddies 82 850G this summer, and the shifting was SOOO much smoother. I can't wait until I can find one of those 92 GS1100G's that had the retro GS look, with 1992 engineering, and was shaft driven!!! That'll be the day man!!!

Second, let me explain how I measure the slack. Maybe that's the problem allltogether. I do it like this.......... I measure at the centerpoint between the two sprockets, and DO NOT press DOWN on the chain, and count that as "slack". I only press UP on the chain, and count that as slack.

Let me say this......... back in mid-summer I took my shocks off, lifted up my swingarm to the point where the chain slack was tightest (which was exactly enough to put a 4x4 under the rear wheel), and set the chain to have just barely any slack at that point. When I put my shocks back on, that corresponded to about 5/8" of slack on the centerstand, at my desired shock pre-set level.

The trouble I'm having is when I set this new chain to that slack, after riding it will stretch to around 1.5" of slack, which I can feel whipping when I decelerate. Then when the chain cools down it will magically go back to the original 5/8" of slack!!!!!

To get 5/8" of slack when the chain warms up, I have to set the "cold" slack at barely any slack at all!!!! I know that can't be good on the chain, sprockets, bearings, and tranny!!!!

Before I went riding today, I adjusted my slack to about 1" (on the centerstand). Took her out riding, and the darn chain was at about 2" of slack when I got done!!!

I HAVE to think it has something to do with the chain grease warming up, as well as the chain itself warming up, that is causing this great magical expanding and contracting chain. I don't really remember this happening so much during the summer!!!!

I'd set it at 2" before riding, and see if it expands to 3" after riding, but that would be WAY, WAY, WAY too much slack!!! I would surely crash and burn!!!

Well, the GS gods have given me yet another riding day tomorrow here in Ohio, so I'll set my slack at 1/2" when cold, and hopefully it will expand to something like 1" when warmed up, which I may be able to live with.

And I gotta give the shafties out there props............ SHAFTIES DO RULE!!! Chains are more "high maintenance" than my frickin' junior prom date :roll: !!

[Dink]

How old is your chain and sprocket set??
a 1" difference is a huge amount, it sounds to me like replacement is called for. I suggest cleaning the chain (on or off the bike as you choose) in kerosene, and i mean really scrubbing it clean, then set it up , also remember every chain will have a tight spot no matter how expensive ort otherwise, you need to find the tight spot and adjust your tension at that point.
Dink
BTW if you do replace the chain, be certain to replace the sprockets as well they MUST be replaced as a set.

[earlfor]

I cant remember exactly the last time the chain on my 1150 needed adjustment, and I'm pushing about 140 hp through it. Its probably been 3 months. I average 2000 to 3000 miles per month. I have said before, chains do not require pretension to operate correctly. In fact, chains and sprockets last much longer if pretension is kept to a minimum. You cant throw a lightly pretensioned chain because the engine's power is pulling the chain ONTO the sprockets, not trying to throw it off. Downshifting is not a problem if the transition is done smoothly using clutch and throttle. A tight chain eats sprockets, burns up bearings and stretches links. Stretched links acclelerate the wear on sprockets and bearings. Its a vicious circle. I just went into the garage and checked the chain slack on the 1150. Sitting on the centerstand, measuring in the center of the return run, the chain at rest is 3 3/4" off the floor. Pushing the lower run up with my finger, it moves to 5 1/2" off the floor. Therefore, I have
1 3/4" of slack in the chain. Part of that is taken up when I sit on the bike, but since I weigh 160 lbs, not very much. When underway, the chain does not jerk, whip or vibrate. The chain is pulled tight on the top run by the engine. It bows out on the return run by centrifugal force. There is no reason it should jerk, whip, or vibrate. Unless, it has been overtightened causing the links to stretch so they no longer match the sprocket teeth. Or, it has not been kept clean and an accumulation of grit and chain goo is keeping the links from moving freely. Or, overtensioning has worn the sprockets out. Or, overtensioning has caused enough heat build up to boil the lubricant out from around the pins and now the pins are dry and galled.

When a new chain and sprockets are installed, the range of use of the chain is 1 1/2 marks on the rear axle adjuster. That is to say, when the chain is installed and first set (with 1 1/2" of slack on the bottom run) and if the first set up is on the 2nd adjustment mark on the swingarm. The chain is WORN OUT when you reach mark 3.5

If you go for a ride of 100 miles and there is 1" difference in the slack in your chain, it should be in the trash can (along with the sprockets). Too much tension will destroy sprockets and chain in a couple of hundred miles. It is probably the most common mistake made.

Earl