Chain broke, pictures tell anything?

[RussMcB]

I broke a chain this past weekend. I'm afraid I don't remember how new it was. I haven't had a chance to put a lot of miles on the car yet, so I wasn't thinking it was ready to be changed (but could be wrong)

The night before the test day I tightened the chain. I suppose I could have tightened it too much, but it didn't seem like it.

I figured I'd post pics here in case someone might have a keen eye and can make an educated guess about why it failed.

A little more info: It's a stock Hyabausa. I was coming out of a 2nd gear corner. I'm pretty sure the two sprockets are aligned well. My chain is shorter than most and the rear sprocket is small, too - 22T (because my Quaife has a reduction gear inside). It was not the master link that failed.

I do have some good, new chain to install, which I'm hoping/expecting will last a while. Maybe I should plan on replacing it pretty regularly.

Thanks for any thoughts.

[DanW]

Hard to tell much from the photos. The pin appears to have yielded with plastic deformation. Not sure the cause, but there does not appear to be much lubricant evident. The pin/plates may have been in a bind.

There are multiple articles on roller chain failure identification available with a google search.

Here are some:
https://www.renold.com/media/291236/Trc_Module_3.pdf


http://www.johnkingchains.com/technical-data/analysis-of-damage-cause-and-remedies/


http://bogaert-transmission.com/imag...e%20chains.pdf

[99sh]

The blue hue on the rollers may be a sign of overheating. When was the chain lubed last?

[Daryl DeArman]

Looks to me like heat/lack of lube.

How does it compare in stretch compared to a new chain?

If you are running an 18f/22r combination with an EVEN number of chain links, your sprockets and chains are going to wear much faster than a 17/22 or 19/22 combination with an ODD number of chain links.

Take a look here: https://www.gearingcommander.com/


This is the link I believe of interest: Optimal teeth-links combination

[ghickman]

Russ is this a 530 chain?

Pretty certain you already know this but lube the chain every session and while it is still warm. Get lazy doing this and they will snap.

I time my chain out after 4 race weekends.

I'm curious as to what type of diff you have that has a gear reduction built into it?

[J Leonard]

press an unbroken pin out, see what it looks like. Maybe no lube outside or inside.

[Brandon Dixon]

The gear reduction in the diff would mean that the chain will be rotating faster than a 1:1 diff. This will mean that the chain links are rotating more often, and with a short chain this will only be compounded. This setup and 'Busa torque may make life for the chain difficult.

[ghickman]

The gear reduction in the diff would mean that the chain will be rotating faster than a 1:1 diff. This will mean that the chain links are rotating more often, and with a short chain this will only be compounded. This setup and 'Busa torque may make life for the chain difficult.

Exactly what I was thinking.

[Daryl DeArman]

The gear reduction in the diff would mean that the chain will be rotating faster than a 1:1 diff. This will mean that the chain links are rotating more often, and with a short chain this will only be compounded. This setup and 'Busa torque may make life for the chain difficult.

Chain speed is the same at a given engine RPM, trans gear, and front sprocket size regardless of final drive ratio.

If by "rotating faster" you mean that the chain is making more rotations per minute, then yes but the variable there is chain length, not drive ratio. (Given the same constants.)

I posted a link that calculates the relative chain wear rate between lengths of chain and sprocket sizes. The idea is to reduce the frequency that the same link ends up on the same tooth.

Ideally the number of links in the chain and the front sprocket teeth count have a very high lowest common multiple. Also nicer on all the bits if the f/r sprocket sizes have a very high lowest common multiple.

[RussMcB]

Thanks, everyone. Have been away from a computer for a half day. Nice surprise to see a bunch of great replies (and links I haven't followed yet).

I haven't been regularly lubing the chain. I thought that wasn't necessary with the newer X-ring chains. But, I don't have a reason to not do it, so I'll start.

Yes, it's a 530 chain.

Good suggestion looking at a remaining pin to see if it shows signs of heat.

My Quaife model is QBA2R. I haven't seen any others in the US but they seemed to be popular in Euro hill climb cars a decade or so ago. https://shop.quaife.co.uk/quaife-cd-...in-driven-cars

[douglap1]

Hey Russ:

Sorry you didn't get to have more laps with us at TGPR.

You should probably check the sprockets and see what they look like.

In my motorcycle experence, we normally change sprockets and chains as a group so that they wear together.

For chain maintenance, I usually clean an X-ring with WD-40 followed by Repsol chain wax.

Good luck,

Paul
FC #21

[RussMcB]

Circling back ...

A few buddies looked at the chain tonight and the consensus was, it was worn out, past when it should have been replaced.

You know the test when you hold a chain out to see how much it bends? This one was didn't do well in that test. And we saw another link that didn't look great (o-ring had come out), and a few rollers looked blueish.

So, I'll put on a new, good chain, lube it often and plan to replace it after a weekend or two and inspect it. And maybe think about routing some cooling air to it.

Regarding chain adjustment, with my shorter run (a little over a foot), if I can move the chain about 1/2", does that sound about right? I expect the new chain will stretch, and I'll need to adjust it after the first session or two.

Thanks for your thoughts.

[Daryl DeArman]

So, I'll put on a new, good chain, lube it often and plan to replace it after a weekend or two and inspect it. And maybe think about routing some cooling air to it.

Regarding chain adjustment, with my shorter run (a little over a foot), if I can move the chain about 1/2", does that sound about right? I expect the new chain will stretch, and I'll need to adjust it after the first session or two.

Thanks for your thoughts.

Hopefully you find that you don't need to replace it anywhere near every two weekends. Use a good chain lube, keep it clean and properly adjusted. If your sprockets are worn they can eat chains pretty quickly. Take a look at the link I posted about chain length. Play with the sprocket size +/- 1 tooth and chain length +/- one link and see if there is some combination that will work for you(ratio wise) and provide a significant improvement in chain/sprocket wear.

[glenn cooper]

Yo Russ, just saw this.
I had a chain come apart very similar to that, on my Nova Dieman.
The brake line T sat directly over the chain run, and I suspect that when I had it apart to split the chassis, some brake fluid dripped on an O Ring, which swole, and finally tore/came off, letting all the lube out.
Like Gary, I life(d)! mine at 4 weekends.
I also inspect every single roller, o ring, plate, sprocket tooth, chain ADJUSTMENT after every session.
I'm not a fanatical chain luber, but I do keep them clean - as you know, the lube is kept inside by the O or X rings.
I'm a bit lost on the even vs odd chain link thing, though...
Do you have a Profi Cat laser chain alignment tool? If not...
That link definitely looks like it got torn, from no lube, prob from no oring, letting lube out.
Cheers, hope to see you soon - ARRC?
(The guy lives like 10 miles from me!)

[Daryl DeArman]

I'm a bit lost on the even vs odd chain link thing, though...

The more chain revolutions it takes for the same link to encounter the same tooth on a sprocket the longer the chain and sprockets will last (all else being equal).


If you had a 18t front sprocket and a 108 link chain, the same link and tooth will meet each other every chain revolution.

If you had a 109 link chain with an 18t front sprocket it takes 18 complete chain revolutions for the same link and tooth to encounter each other.

If you have an odd numbered drive sprocket you would want an even number of links in the chain.

[RussMcB]

Yo Russ, just saw this.

Do you have a Profi Cat laser chain alignment tool? If not...

Thanks, Glenn. No, but I'm able to lay a straight edge on both sprockets and it's true (as best I can tell).

Interesting about the brake line tee. I had a couple of oily outings, so I've degunked the engine bay a bit. Maybe ...

Yes, I'll be at the ARRC. Looking forward to it. See you there.

[griceiv]

The more chain revolutions it takes for the same link to encounter the same tooth on a sprocket the longer the chain and sprockets will last (all else being equal).


If you had a 18t front sprocket and a 108 link chain, the same link and tooth will meet each other every chain revolution.

If you had a 109 link chain with an 18t front sprocket it takes 18 complete chain revolutions for the same link and tooth to encounter each other.

If you have an odd numbered drive sprocket you would want an even number of links in the chain.

I think he is just pointing out that all chains are even link counts unless you use a half link.

[Daryl DeArman]

I think he is just pointing out that all chains are even link counts unless you use a half link.

Perhaps. Wasn't sure if he was confused about the math or the theory. Half links are readily available. Though it might be easier/more desirable to just utilize an odd-numbered countershaft sprocket.

[JerryH]

Just saw the bit about degunking the engine bay.

Avoid getting any degreaser or cleaner on the chain. Wipe it with a cloth if needed. Never clean it with anything!

Frankly, I don't advise using harsh cleaners on any part of a race car. I clean suspension parts and other steel parts with wd-40....often.....and always after a rain race.

Like Glen and Gary said.......lube every session......and replace on a schedule. I prefer to use a chain lube that goes on in a foam.....dries clear......and doesn't sling off.

Jerry Hodges
JDR Race Cars

[RussMcB]

Thanks, Jerry. I agree 100%. Afterwards when I thought of all the degreasing, it seemed obvious what I had done to hurt the chain's seals.

I watched a YouTube video of someone doing a thorough job of cleaning a chain (on a street bike after thousands of miles) and they used diesel fuel (in a spray bottle) to loosen the oil/road grime. That seemed like a good idea, pretty harmless to the chain. Hopefully I wont have oily messes to clean up in the future. I raced recently and no leaks! (Thank, God).

What type of foam oiling do you use? Here is what I'm using:

[Daryl DeArman]

I utilize non O-ring/X-ring chain. I can clean it thoroughly without any concerns about seal damage. I also can ensure that the lube gets into the pins/rollers, rather than count on factory lube that may/may not still be in there. The chain is less expensive, lighter, and has less friction. Differences are minimal, but at fairly frequent chain replacement intervals I don't see the logic behind the sealed chains.

I use Bel-Ray Superclean. It does a fantastic job, only drawback is that it dries white. It's a bit more expensive than the Maxima stuff. I used Maxima 2-stroke oil so I love many of their products, I just prefer the Bel-Ray on my chains.

My application is different, but I have always enjoyed relatively great chain life.

[Mike B]

What type of foam oiling do you use? Here is what I'm using:

I've used that Chain Wax since 2007 and the only broken chain was due to a faulty rivet (user error). I also lifed my chains at 4-5 events.

[JerryH]

Tried the non o ring chains. Yes....lighter and less frction.....but two weekends max. Really marginal on second weekend.

Using 530 zzz chain and chain guard by Maxima. we are now going 6 weekends on a regular basis. No chain failures so far in 5 years.....on multiple cars. Went 8 weekends once, but that is pushing it.

Did have chain come off for another reason....adjuster bolt loose.

Chain lfe is very dependant the on chain alignment...or sprocket alignment to be more prcise......and proper adjustment (to loose is better than to tight).

Jerry Hodges
JDR

[Daryl DeArman]

Tried the non o ring chains. Yes....lighter and less frction.....but two weekends max. Really marginal on second weekend.

I don't doubt your experience. That's ludicrous chain life. Perhaps the real solution is a chain and sprocket combination more suited for the job, and I don't pretend to know what that is. However 530 chain should be good for 1.5x the HP levels a FB produces. So, why the extreme wear rate?

If you are only going to get 2-4 races from a chain, maybe 428 chain will also last 2-4 races at considerable weight savings. Maybe you have to pay a weight penalty and go with 630 chain that will last an entire season.

Obviously, chains and sprockets are wear items, but not approaching the replacement intervals of tires.

[TDI PILOT]

Keep in mind the replacement interval Jerry mentioned isn't running the chain all the way to failure. Its a conservative replacement interval keeping in mind what happens and what is at stake when a chain goes. To me its not worth driving 24 hours round trip and spending all the money on entry fees, tires, meals, race gas , and many other things including punching a hole in your $5000 engine and DNF'ing a race while leading trying to eek out another race on a $100 chain. I run a 520 DID ZZZ X-ring on my F600 and I typically replace it every 4 race weekends or so.
-Eric

[Daryl DeArman]

Eric, I certainly agree with the logic.

I'm suggesting that if chains are being replaced because of wear and not because of catastrophic failure, then it may make sense (and be a performance improvement) to utilize a chain that is both lighter and less expensive. Chains with more pins per inch last longer provided the side plates provide the required strength.

Bigger isn't always better. There's a reason you don't utilize 630 chain.

[10rmotor]

Inspect the chain after every session. it will tell you when its time. Missing o-rings are one obvious sign. Pay close attention to the rollers - they will start to look pitted, and may also start to turn blue. Also, the rollers will start to open up and their seam will begin to show. Eventually they will start to spit the rollers off the pins before ultimate failure.

I check the tension after every session too. It needs to be checked in multiple locations, so rotate the chain while the rear end is up in the air to do this. It should be able to move up and down about one chain thickness.

[glenn cooper]

Just saw the bit about degunking the engine bay.

Avoid getting any degreaser or cleaner on the chain. Wipe it with a cloth if needed. Never clean it with anything!

Frankly, I don't advise using harsh cleaners on any part of a race car. I clean suspension parts and other steel parts with wd-40....often.....and always after a rain race.

Like Glen and Gary said.......lube every session......and replace on a schedule. I prefer to use a chain lube that goes on in a foam.....dries clear......and doesn't sling off.

Jerry Hodges
JDR Race Cars

HOLD UP! I'm not an excessive luber! I clean the chain WD40 on a rag when it needs it. Never had a problem with the WD - that stuff is pretty much weasel piss, anyway.

[DanW]

HOLD UP! I'm not an excessive luber! I clean the chain WD40 on a rag when it needs it. Never had a problem with the WD - that stuff is pretty much weasel piss, anyway.

Well Giancarlo, it certainly isn't BG or JB, but it is simply stoddard solvent and mineral oil(some say turbine oil) with a fragrance added.

[mark elder]

Hi

The broken bit and the bits around it are all blue. Only heat causes blue. Heat comes from friction. Friction is reduced with proper alignment (a little) and lubricant (a lot). And it looks dry as a bone.

Most brake cleaning products swell O rings (and indeed brake seals strangely enough; its a simple experiment; get two seals, squirt one, wait, then compare both after a day; some stuff will swell them within an hour). Ask me how I know.

I guess you have BOTH lost some O rings and also not lubed it enough. Bad combo.

Chain wear is a separate issue. The best test it how much longer the worn chain it (this adds up the wear of the actual pins/rollers/plates etc etc). Not sideways flex which measures different things.

Put a new chain next to the worn one. 1% longer is OK, 2% reasonable, 3% is a throw away (so a metre of chain that is now 1% longer is 10mm longer; so half a link longer is OK, a whole link is not).

[DanW]

Chain pitch gages are also available from most industrial suppliers like Motion Industries. You can use them to check wear with the chain on the car.

[RussMcB]

Chain pitch gages are also available from most industrial suppliers like Motion Industries. You can use them to check wear with the chain on the car.

Interesting. I Googled and found one specifically for FB race cars:

https://www.fbchain.com/chain-wear-gauge-solutions

(bad joke - I just noticed the company's name)

BTW, we're 99.9% sure my problem (original post) was because I degreased the back of the car several times after significant oil leaks. Later, after helpful responses earlier in this thread, it was a "Duh" moment, and we realized I had ruined the chain's seals causing it to fail even thought it had very little time, made worse by not lubing or checking it regularly. I know better now.

On edit: This chain checker looks decent. It's in the UK. Anyone know of a better one? Thanks.

https://www.ebay.co.uk/itm/Chain-Che...25816#shpCntId

[john f]

Interesting. I Googled and found one specifically for FB race cars:

https://www.fbchain.com/chain-wear-gauge-solutions

(bad joke - I just noticed the company's name)

BTW, we're 99.9% sure my problem (original post) was because I degreased the back of the car several times after significant oil leaks. Later, after helpful responses earlier in this thread, it was a "Duh" moment, and we realized I had ruined the chain's seals causing it to fail even thought it had very little time, made worse by not lubing or checking it regularly. I know better now.

On edit: This chain checker looks decent. It's in the UK. Anyone know of a better one? Thanks.

https://www.ebay.co.uk/itm/Chain-Che...25816#shpCntId

A dial caliper would do the same thing.

john f

[RussMcB]

A dial caliper would do the same thing.

john f

Well, not exactly the same thing. That tool looks kinda like a go/no go gauge.

But maybe I’m not imagining how you’d do it with a dial caliper. Would you mind elaborating?

[john f]

Well, not exactly the same thing. That tool looks kinda like a go/no go gauge.

But maybe I’m not imagining how you’d do it with a dial caliper. Would you mind elaborating?

You measure over "x" number of roller pitches. If chain pitch is .5 inches and the roller dia is .4" you put 6 rollers inside the caliper the length should be 2.9" (5 chain pitches plus one roller dia.) . Now add 1% or 2% or whatever to the 5 pitches and that is your upper limit. All this should be done with the chain under some sort of tension.

john f

[cjahn]

Hate to hijack this thread but it is related....

Whats the chain to use. (Brand). Intention is a RK 530 or a DID.

I have had success with DID (And a riveted link). Lube every session. Clean every event.

Planned on this (need 2): D.I.D 530 Pro-Street VX Series X-Ring Chain - 114 Links - Gold, Manufacturer:
https://www.amazon.com/D-I-D-530-Pro...30+Chain&psc=1

THX
Cj

[RussMcB]

It's been a while since I researched, but at the time I convinced myself this one had about the best specs:

RK 530 Max-Z

I recently bought some from here:
https://www.2wheel.com/rk-530-max-z-chains.html

[cjahn]

Thanks Russ!

What car? and length?

I have a Stohr FB

Cj

It's been a while since I researched, but at the time I convinced myself this one had about the best specs:

RK 530 Max-Z


I recently bought some from here:
https://www.2wheel.com/rk-530-max-z-chains.html

[99sh]

Everyone has their "best".

DID 530ZVMXG is a popular choice and what I run.

[openwheeler37]

Hate to hijack this thread but it is related....

Whats the chain to use. (Brand). Intention is a RK 530 or a DID.

I have had success with DID (And a riveted link). Lube every session. Clean every event.

Planned on this (need 2): D.I.D 530 Pro-Street VX Series X-Ring Chain - 114 Links - Gold, Manufacturer:
https://www.amazon.com/D-I-D-530-Pro...30+Chain&psc=1

THX
Cj

I've been using this chain for years. One chain lasts all year. Also use rivet style master links.

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1