I am a cheapskate!

[powerslave]

So,I'm adjusting my chain the other day,and it's reached the "replace"mark on the chain guard.
I took a good look at the chain and it has no tight spots,and no evidence of O-ring faiure....it's just stretched.
The sprockets look perfect as well,do distortion on the teeth at all...
Here is my cheapskate thought:why not just take a link(or 2) out of the chain to get it back near the "new" mark on the chain guard????
Can this be done?
Should this be done?
If this is a bad idea,please advise,because I thought it was pretty brilliant!

[drewl]

sure it can be done, but I wouldn't

If you were to remove a link, you would have to replace it with a clip type master link. This will not match the original chain, therefore making it the weakest link and subject to failure.

I had the same problem this spring. I bought an RK chain and replaced it, but not the sprockets because they were dang near perfect. With all the riding I did this summer, and the increased flogging recently, I am glad I have a good chain.

[Cyborg]

Questioned in order:

A) Because the stretch, however even, also indicates at least some degree of metal fatigue
B) Yes
C) No

IMO, not worth the risk...

[Longerfellow]

You also should watch for tight spots. Your chain may be tighter in some spots than in others. Check its tension in various locations.

[SCraig]

I agree, it isn't worth the risk. I found this information:

Chain drives require tensioning on a regular basis. Industry standards recommend chain replacement when the chain has "stretched" by approximately 3%. When the chain has "stretched" 3%, it is heavily worn. All the components of the chain: rollers, pins and bushings, have lost their case hardened surface, and failure is imminent.

on this PDF file: http://www.gates.com/facts/documents/Gf000379.pdf Admittedly it pertains to roller chains in general and not motorcycle chains specifically, but a roller chain is a roller chain and Gates has been making them for a long time.

I also found some other guidelines that state that the 3% stretch limit is for non o-ring chains. O-ring chains should be replaced when the stretch exceeds 1% of the overall length.

The bottom line is that you could probably get some more miles out of it but why take a chance? If it breaks the BEST that can happen is that you will be stranded. I don't even like to think about the worst.

[Lgn001]

I don't know how often chains fail anymore. If/when they do, however, there is a possibility of the rear wheel locking up and/or the chain punching a big hole in the side casing, in addition to destroying the clutch slave cylinder. And most chains probably don't break at 10MPH; they'll break at 45 plus. Think high horsepower chainsaw... Like SCraig says, even if nothing catastrophic happens, you'll be stranded. Murphy will make sure it happens at the worst place, worst time, etc.

[powerslave]

Thanks for the advice,guys.
Looks like my "brilliant" idea wasn't so brilliant after all.
I guess i'll just have to invest in a new chain/sprockets.
I kind of knew there would be a good reason why this was a bad idea!!
Thanks again!

[VFR_Bulldawg]

You're making the right choice. I'm an engineer and my specialty is in jet engine and aircraft repairs so I have a decent amount of experience working with fatigued metals. Replace your chain when it hit the replacement mark. I won't bore you to death with the finer points of metallurgy but I'll say you can't see the wear and tear on the metal with the naked eye, but believe me it's there.

For some anecdotal evidence, I'll tell you a story about my best friend and his old 03 Yamaha R6. The chain wasn't at or past its max useable life, but it broke on him anyways. He lived in Vail, CO at the time but when it broke he was in the middle of nowhere in Utah on a long road trip. He was on the highway doing about 80 when it broke and the chain hit the crank case so hard it put about an inch wide hole in it. It would have cost a ton of money to rent a truck, drive that thing home, and then fix it. He was lucky to get some help from a local guy who happened upon him and his friend. He was able to get it into the next town and trade it in on a new 08 GSXR-750, but he got way less than what that bike would have been worth without a busted crank case.

Now imagine the chain breaking while you're having fun, going fast, and leaned way over in a tight curve with a drop off or a guardrail on the outside. You won't be able to hold the curve with no power. Yes it's worst case, but not a impossible.

[slippy]

Yea, my chain broke on me earlier this summer. If you are a cheapskate, it will be much cheaper for you to buy a new chain now instead of buying a new chain, new clutch rod, new slave cylinder, new sprocket cover, new clutch rod seal, new chain guard (this is assuming you're doing less than 35 or so). And that's just damage to the bike.

[eddievalleytrailer]

I have taken links out of a chain before. But, it was on a dirt bike. A chain doesn't really "stretch". The pins and the holes they are in wear. The pins become smaller and the holes become larger. This slack between the pins and holes is what causes the chain to become longer. Since the pins are smaller, they are weaker.
BTW The dirtbike chain broke shortly after cutting a link out. You guessed it....in the middle of nowhere on a Sunday afternoon when I was all by myself and before the days of cell phones. I'd spring for a new one as well as a new front sprocket.

[VFR_Bulldawg]

Originally Posted by eddievalleytrailer

A chain doesn't really "stretch". The pins and the holes they are in wear. The pins become smaller and the holes become larger. This slack between the pins and holes is what causes the chain to become longer.

I'm going to have to disagree with you on that, because I'm quite sure that the links do stretch. I'm a noob to motorcycles, but not a noob to metals and stresses.

(WARNING: THE FOLLOWING IS WRITTEN BY AN ENGINEERING NERD, WHICH IS A REDUNDANT TERM TO BE SURE)

Any metal that is under cyclical tensile loading of any significant amount will physically stretch and fatigue. If Honda made the chain large enough that the tensile load from the engine were to be insignificant I'm pretty sure we'd all be complaining about how large and heavy the chains on our bikes are. Everytime a chain link makes a revolution and the engine and rear wheel are mechanically linked by the transmission the link is loaded and unloaded once. The stretch is immeasurably small on a per revoluation basis, but over the huge number of times your chain makes revoluations it adds up.

This stretching and fatigue will naturally occur at the location in the link with the smallest cross sectional area since this is the weakest location in the link and the location of the highest stress. This is of course at the pin holes. While there is undoubtably wear between the pins and pin holes, some of the slop you would see in the pin holes would very probably be from the metal stretching leaving the pin hole with a very slight oval shape. This oval shape should actually cause the rate of wear between the pin and pin hole to increase and become uneven.

I'm not totally disagreeing with you, EVT. You raise an excellent point about wear on the contact surfaces of the pins and pin holes and the resultant slop. The "stretch" in the chain over its useful life would probably be most accurately described as a function of both metal fatigue and pin and hole wear.

I will stop boring you guys now. If you can't tell, yes I am a nerd.