Measuring chain stretch with a tape measure??

[clean]

Hi guys,

Wondering if anyone can let me know if I'm doing this right. the book says 12.57" for 21 pins. I was measuring with a tape measure, and got about 12 9/16" which is about the limit?

anyway I also measured a brand new ZVMX and its a little shorter but pretty close. I'm guessing this measurement needs to be way more precise then what a tape measure can produce?

Im also guessing most of us dont have a pair of 12" calipers, however I do have an 8" pair. I took 12.57 / 21 = .5985

so .5985 x 13 pins = 7.781. 13 pins on my chain measures 7.544 ...... something doesn't seem right? how could it be approx. .200 under?

 

[ZeePopo]

I always have a hard time measuring chain stretch. Hopefully someone will chime in soon with advice.

 

[WuzzaCBXRider]

I always have a hard time measuring chain stretch. Hopefully someone will chime in soon with advice.

I don't recall ever thinking about measuring chain stretch. Not ever.

 

[clean]

I don't recall ever thinking about measuring chain stretch. Not ever.

I have a bad case of OCD

 

[Berlin Germany]

@clean

first of all get and then read the manual.

every chain manufacturer specifies a length wear factor of 0.5%.
and suzuki does the same.
the manual even gives a specific value - 319.4mm / 12.57" between (inside measured) 21 pins on the 530 chain.
see page 2-21 (+/- 1) for gen1 or 0B-17 (+/- 1) for gen2

to be able to estimate the wear (without a slide gauge ), one tries to pull the chain at hight of the wheel axle horizontally backwards from the rear sprocket.

prerequisite: the chain has the prescribed slack (or a little bit more).

If now the chain can be lifted more than 1.5 mm from the sprocket, the chain is worn and the chain set must be completely replaced.
at the same time you can also look at the teeth of the sprocket - if they are pointed or washed out, this is also an indication of a worn chain set.
see example pics at page 3A-5 (+/- 1) for gen2 or 6-44 (+/- 1) for gen1.

 

[clean]

@clean

first of all get and then read the manual.

every chain manufacturer specifies a length wear factor of 0.5%.
and suzuki does the same.
the manual even gives a specific value - 319.4mm / 12.57" between (inside measured) 21 pins on the 530 chain.
see page 2-21 (+/- 1) for gen1 or 0B-17 (+/- 1) for gen2

to be able to estimate the wear (without a slide gauge ), one tries to pull the chain at hight of the wheel axle horizontally backwards from the rear sprocket.

prerequisite: the chain has the prescribed slack (or a little bit more).

If now the chain can be lifted more than 1.5 mm from the sprocket, the chain is worn and the chain set must be completely replaced.
at the same time you can also look at the teeth of the sprocket - if they are pointed or washed out, this is also an indication of a worn chain set.
see example pics at page 3A-5 (+/- 1) for gen2 or 6-44 (+/- 1) for gen1.

you said inside measured? don't you mean center to center of pins? instead of 21 pins, what's the max distance for 13 pins?

 

[Berlin Germany]

@clean

man, read the manual & look at the drawings - if nec. use a magnifying glass - pagenumbers i told you - follow that prescriptions and all is fine.

 

[Mythos]

anyway I also measured a brand new ZVMX and its a little shorter but pretty close. I'm guessing this measurement needs to be way more precise then what a tape measure can produce?

Im also guessing most of us dont have a pair of 12" calipers, however I do have an 8" pair. I took 12.57 / 21 = .5985

so .5985 x 13 pins = 7.781. 13 pins on my chain measures 7.544 ...... something doesn't seem right? how could it be approx. .200 under?

Yes a tape measure is a crude method of measuring chain stretch but I use a tape measure. measure center of pin to center of pin as best as possible and measure three different sections of chain. Take an average. LOL with a tape measure you probly won't get a definite difference but if your observant, you can get an idea.

In my opinion, you're expecting results that are too precise. Measure three spots and if it looks very close to max, change the chain. If it's over 12 and 1/2 inch at all, change it soon. Measure the brand new chain across 21 pins for kicks. It won't be a lot less than 12.5 inches. Twenty-one pins is only about one sixth of the total chain length.

 

[clean]

Yes a tape measure is a crude method of measuring chain stretch but I use a tape measure. measure center of pin to center of pin as best as possible and measure three different sections of chain. Take an average. LOL with a tape measure you probly won't get a definite difference but if your observant, you can get an idea.

In my opinion, you're expecting results that are too precise. Measure three spots and if it looks very close to max, change the chain. If it's over 12 and 1/2 inch at all, change it soon. Measure the brand new chain across 21 pins for kicks. It won't be a lot less than 12.5 inches. Twenty-one pins is only about one sixth of the total chain length.
View attachment 1637149

im not sure if im trying to be too precise. The new and old chain are very close with the tape measure (about a 1/16)

anyway I was trying to divide the 21 pins down to a smaller amount so I could measure more precise with my 8" caliper. The max for 13 pins should be 12.57" / 21 =.5985 x 13 pins = 7.781

mine was a fair bit shorter then that by about .200 so either my chain is fine or I'm doing something wrong. Don't have time to dive in again right now, but will report back when I get it figured.

 

[WuzzaCBXRider]

Why are you doing this? I (have) pulled on the links on an old chain during a service, to see if they pull too far away from the rear sprocket but I’ve never measured the links in a chain. Are you just trying to compare a used chain to a new one?

 

[clean]

Why are you doing this? I (have) pulled on the links on an old chain during a service, to see if they pull too far away from the rear sprocket but I’ve never measured the links in a chain. Are you just trying to compare a used chain to a new one?

The service manual suggests to replace the chain if 21 pins center to center exceed 12.57" or 319.4mm .

Other then a tape measure I have nothing that will measure that big accurately. I do have an 8"/200mm caliper so I measured 13 pins and compared new to a low mile chain, and a 18,000 mile chain.

The new chain was 190.8mm
The low mile chain was 191.3mm
The 18000 mile chain was 191.5mm

Going with the 0.5% max allowed stretch limit the 18000 mile chain is close , but still in spec by 0.254mm (over 13 pins).

First gen chain is 112 pins. 112 / 13 = 8.615 x 0.254mm = 2.18mm more stretch left in overall length of chain.

Sorry guys, really went down the rabbit hole on this one .....

 

[WuzzaCBXRider]

I may have missed this but you’re a brand new rider with his first ever motorcycle?

 

[Mythos]

You are trying to be too precise, I think. Measure the stretch and make a judgement. If it's at the limit, change it. A lot has to do with sprockets too. If you r sprockets are alomst used up, change all chain engine sprocket and rear sprocket.

im not sure if im trying to be too precise. The new and old chain are very close with the tape measure (about a 1/16)

1/16" is a great deal. Remember, you are measuring approximately 1/6 of your total chain stretch when you measure 21 pins. So the difference is more like 3/8" if you were to measure the total chain stretch across the whole chain. That's a big difference between old and new.

 

[Mythos]

...not to say being too precise is a bad thing, just use that OCD toward something that will really matter like your valve lash clearances.

 

[ottafish]

I just work on the theory I change both sprockets and chain all at the same time.
Rear sprocket is worn, replace as a 3 piece set.
Can't say I've ever worried about chain stretch on this basis

 

[HayaWakened]

Sorry guys, really went down the rabbit hole on this one .....

I strongly encourage you to keep the 'rabbit hole' attitude, esp as it pertains to bikes. It will enrich your riding...

...not to say being too precise is a bad thing, just use that OCD toward something that will really matter like your valve lash clearances.

...but ... killer chains at about $150 last 10 - 20 k mi, AT LEAST. Ima have to side with Mythos DeerKiller on this one

 

[Kiwi Rider]

I just work on the theory I change both sprockets and chain all at the same time.
Rear sprocket is worn, replace as a 3 piece set.
Can't say I've ever worried about chain stretch on this basis

Exactly my approach also . . . dont think I've ever measured chain stretch, I just look at the sprockets wear, and if the chain can be picked up off the rear sprocket and decide on that basis if it needs changing or not.

 

[Dopey]

@clean

man, read the manual & look at the drawings - if nec. use a magnifying glass - pagenumbers i told you - follow that prescriptions and all is fine.

I don't know if it's me taking what you say the wrong way or what but while you do seem to try and be helpful just telling someone repeatedly to read the manual is a little d!@%headed. Some people grasp things better by having someone explain in a way different then the manual. Not to mention that if all anyone needed to do was get and read the manual which seems to be how you respond to everyone's questions then there wouldn't be much need for this awesome forum because we could all just read the manual with our magnifying glasses and fix everything without asking anyone else anything. I am a mechanic for the same reason you are, because not everyone is able to easily comprehend how things work or are explained in a book and alot prefer to spend money paying mechanics to do it for them which I'm thankful for. And for those trying to understand and ask questions I'm more then happy trying to explain and teach them what I can in a way that's easier then reading a manual. So if I'm taking what you said wrong I'll gladly apologize but if you don't want to help someone with a question just telling them to read the manual isn't real helpful.

 

[clean]

I may have missed this but you’re a brand new rider with his first ever motorcycle?

well not exactly. I use to ride one of those rare Honda bikes with an inline 6 cylinder. I currently only own two busa's though

also agree with everyone's assessment of just checking out the sprockets, and giving the chain a lift off the rear sprocket, and calling it a day.

I was just trying to look solely at chain stretch as the book suggests ... but without a 12" caliper as I dont have one.

thanks for everyone's input.

 

[Kiwi Rider]

I don't know if it's me taking what you say the wrong way or what but while you do seem to try and be helpful just telling someone repeatedly to read the manual is a little d!@%headed. Some people grasp things better by having someone explain in a way different then the manual. Not to mention that if all anyone needed to do was get and read the manual which seems to be how you respond to everyone's questions then there wouldn't be much need for this awesome forum because we could all just read the manual with our magnifying glasses and fix everything without asking anyone else anything. I am a mechanic for the same reason you are, because not everyone is able to easily comprehend how things work or are explained in a book and alot prefer to spend money paying mechanics to do it for them which I'm thankful for. And for those trying to understand and ask questions I'm more then happy trying to explain and teach them what I can in a way that's easier then reading a manual. So if I'm taking what you said wrong I'll gladly apologize but if you don't want to help someone with a question just telling them to read the manual isn't real helpful.

Although I completely understand where you’re coming from, and you’re absolutely correct about the fact that a large percentage of people find it difficult to comprehend engineering concepts, you must realise that our good friend Frank (Berlin) is German, and Germans in general have a precise way of looking at engineering.
They are not known for taking short cuts or guessing. They’re ‘by the book’ types of people and Frank is no exception.
So in summary, Frank is trying to be helpful by always stressing, “read the damn manual!!”, he is right in that reading the manual IS the best source of CORRECT info re the repair of the bike.
But you’re right also in that you like to share with mechanically illiterate people your understanding of the bike’s systems and the reason for why some components have failed and best way to repair that failure.
I too am a mechanic ( lifelong working in the trade) and I’ve met a lot of mechanics only to learn there are various ways of tackling a job, some guys are extremely efficient and some take a longer way around the problem to reach the end goal... (being the repair), some guys are really good at electrics but terrible at other things and so on.
We all have our strengths and weaknesses is what I’m trying to say here.
One thing I’ve noticed is that reading the factory service repair manual is usually the last resort for many mechanics, I’m guilty of that too, but when I do look at the manual BEFORE tackling the job at hand, it does make it easier and the job goes smoother.
So I do think you took Franks comments the wrong way and please don’t insult him inferring he’s a d***head, he’s actually extremely knowledgeable having worked on Busas for almost 20 years and many other bikes too... and he’s read every service manual front to back.
That’s my 2c on the subject.