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Ironman sprockets

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Posted by: lobotomy---------------------

Has anyone tried an Ironman Sprocket? They're more expensive than a Renthal, etc. but the specs look pretty impressive. Any thoughts? There's a website with info on them: http://ironmansprockets.com/


Posted by: MikeT---------------------

I bet the steel sprockets from Rocky mountain will last a good long time.


Posted by: dell30rb---------------------

Yeah... Reel cheep too!


Posted by: Jaybird---------------------

They can make sprockets out of inconel or spacecraft titanium and it still won't make one iota of difference. Running an aluminum sprocket will tell at a glance when your chain has reached its limit...a hard sprocket will not show the wear until damage of the chain has occured and breakage is probable.
The only plus to buying a hard sprocket is that IF you measure and stay up on where your chain growth is, you can replace the chain after it has grown about 2-3% and get by without replacing the sprocket. Many wait until they see sprocket tooth damage....with a hard sprocket showing tooth wear, your chain has reached it's potential long ago and you are riding on borrowed time.
Bottom line for me is, only those who are very careful to check and change their chains often should ever run a hard sprocket.


Posted by: jeb---------------------

I don't agree with Jaybird. I think running a steel rear sprocket with a good quality sealed chain is the way to go, especially for offroad. I think having a rear sprocket that lasts longer causes the chain to last longer, too. Aluminum is soft and hooks quicker which, IMO, puts more strain on the chain making it wear out sooner, too. There are measurements listed in my owners manual for chain limits but, even on the sealed chains I've replaced, I've never seen one past or really close to it's limit.

I still wouldn't ever use a old chain with a new sprocket or visa-versa, of course. You should always replace the sprockets and chain at the same time.


Posted by: lobotomy---------------------

Thanks for the input. I tend to believe, like Jeb, that a harder sprocket will increase chain life (longer sprocket life = longer chain life). However, I think that Jaybird is right by saying you need to keep tabs on chain stretch. Thanks again.


Posted by: Jaybird---------------------

I should let this drop becasue so many have things in thier head and can't seem to be changed no matter what they see or hear.
BUT...I can't let it go, because I know that there is some confusion on this topic and some folks may actually enjoy the facts.
Not trying to be a butt, just want to be clear that this is something that I challenge anyone to prove me wrong on....anecdotal information excluded.

Ok....Jeb, I know you are a KTM man, so let's use KTM info. I believe your manual will state that you should measure a distance of 18 reels to check for wear. In that distance you should have no more than 272mm. They advise you to change out the chain when it reaches that measurment. Well, KTM does this so that you won't blame thier chain wear recommendations on the wear of your sprockets. This measurment is WAY shorter than what a chain can run and not deform the sprockets...reguardless of sprocket material.
Bear with me here....a 520 chain has a new pitch of .625" or 15.875mm,
so if you measure 18 reels (which by the way is 17 spaces since the first reel is #1....look at the picture in the manual if you must) should have a measurment of 10.625" or 269.875mm. Before I go further I want to add a quote from a chain website:
Quote:
Chain wear life is usually 1.5% elongation (often measured over 6 to 12 pitches) in drive applications and 2% elongation in conveyor applications. Chains can operate up to 3% elongation, but there may be sprocket damage, unexpected loading, or increased vibration and noise.

This was from http://www.ustsubaki.com/
Now, the KTM manual states that the chain needs replacing when a distance of 18 reels(17 spaces) measures 272mm. This would be a growth of less than 1% of the new length(actually less than .9%). Any quality roller chain will last and provide good service much longer than the KTM manual states.

Now, Jeb...if you have changed out your chains because the sprockets had shown damage or "hooking" then I garantee your chain was Way past what your manual states is max. If there were no signs of wear on the sprocket, and you said that the chain had not even come close to recommended growth...why did you change anything out? IF that were true, there was no reason to change things out. I know some state that they change out every year "like you should"...well that is a load. You SHOULD change out chains when they have grown past max tolerence. Most all chain MFG's agree that chains will function to spec at up to 3% of growth. The problem with letting them go that long is that there will no doubt some noticible damage to the sprocket teeth. In that instance one should change out the whole set-up.
If you do in fact decide to change out the chain before it has grown past 1.5%-2% of original length, then you can still run the same sprockets as there will be no visible(or measurable) signs of wear on them.

I still maintain that if you run a steel or harder sprocket...then you run the risk of letting your chain go too long before you change it out. Only if you keep an eye on the chain and don't let it get past 2% growth will you not see any wear on the teeth...that is if you are lubricating properly. Only if you watch your chain on a daily basis and know when to change it out should you run a hard sprocket. Usually a harder sprocket can take the chain growing to past 3% without damaging the teeth, BUT the hardened teeth WILL cause a very accelerated death of the chain from that point if the chain is not changed. Actually risking breakage.

Take a good look at how you are measuring things, Jeb. Then go to the website I mentioned above and enjoy lots of good reading.


Posted by: jeb---------------------

Thanks for the post, Jaybird. I will take another look at the manual. The last time I actually measured stretch was on my 98 380MXC and I used that bike's owners manual measurements for chain wear. After a year of riding with that monster motor, the chain, the stock DID 520VM xring, was well within tolerance. Since that one was, I assumed all the follow on, less powerful bikes would be, too. Maybe not, though.

You're saying that if you toss the chain before it gets to 1.5-2% growth, you can reuse the sprockets. I'd personally never reuse any components when replacing the chain so this is of no benefit to me. I find that using a DID xring chain (the most expensive part of the deal) with good quality steel rear sprocket, I can easily get a year out of the setup with very low maintenance. Wash it with soapy water, rinse it off, let it dry and lube it with Honda HP chain lube is all I ever do. For me, this is, by far, the most economical route compared to putting on several $80 chains in season.

[q]Well, KTM does this so that you won't blame thier chain wear recommendations on the wear of your sprockets. [/q]

Where did you find this out? And I don't understand why I'd blame KTM for that anyway?


Posted by: Jaybird---------------------

Jeb,
I understand that you change everything out, and usually that is the best advise to give someone...BUT if you change out the chain before it has reached 1.5-2% growth, then you can in fact run the same sprocket.
There is the economy of a hard sprocket. An aluminum will also make it just about as long, but when you reach about 2% growth on the chain, you will start to see the slightest bit of wear on the teeth, especially with a HP monster.

There is no blame of KTM, other than a chain will last much longer than their recommendations state. It's kinda like when Eric **** tells you that MFG's recommend a mix ratio of 20:1 to ensure you use plenty of oil. He's in that business and he knows this to be fact just becasue he does. Same with chains and sprockets, they are part of my livelyhood and I better know what I'm talking about.

BTW...approx. 54 hours and counting on a standard chain with chrome-moly front and aluminum rear.
Do take the time to read the info at www.ustsubaki.com Worth the read.


Posted by: dave186---------------------

For people like me that buy sprockets based on looks, those Ironman sprockets sure do look trick!


Posted by: jeb---------------------

Jay,
I did take a look at the manual and the website. You're correct in that the KTM spec doesn't allow much stretch. I guess it boils down to what's the most economical and reliable setup for *me*. I've found that using the xring chain with good steel sprockets and the maintenance I describe will get me easily through a season of riding that usually includes lots of deep mud, sand, etc with no problems for about $120.


Posted by: ml36---------------------

jaybird - i totally agree with you on the idea of proper chain maintenance. but, i disagree with you on the fact that a aluminum sprocket will last as long as a steel or stainless sprocket. friction is friction, and knowing the properties of the two metals will tell you that the aluminum will wear faster than the steel. i ride mostly in the woods and if i race, it is only hairscrambles. i don't care what you spray on the chain, as soon as you hit a few mudwholes and the chain is completely covered with gritty mud, there is zero lubrication between the roller and sprocket. now, if you ride mostly mx, i could see how you get comparable life out of an aluminum sprocket, but for the woods, they will not hold up as well.

you have however gained my attention on the matter of chain elongation. i admitt that i never measure this quantity and like to change the sprockets/chain as a set. since i just payed 130$ for a ti-moly superman rear sprocket, i think i will give your theory a try.

just curious, how many chains do you go through before you replace an aluminum sprocket, and do you replace the driver at the same time as the rear?


Posted by: Jaybird---------------------

Guys, I don't want to loose your interest in this thing....you are getting real close to understanding where I'm comming from, but I need to touch on a few things. To do this properly, I need to post some pics.
I am a total non-digital guy at present, but I will have the shots put on a disk so I can post them. Give me just a couple days to get it together and I think you will be interested in my reply to the last threads.

btw...Jeb, I have no qualms with your procedure other than I feel if you are going to use the hard sprockets, get the use that they were inteded to give you before you change them. If there is no visible deformation of the teeth, then it's still a usable item(there is no invisible wear or stretch on a sprocket, what you see is what you get). Just don't let the chain get past spec and you should get good life from any hard sprocket. That alone will reduce your yearly spend.

Be back soon......


Posted by: MikeT---------------------

Just latching on. I'd like to see the pics.


Posted by: mark_england---------------------

anyone seen the stealth rear sprockets?
aluminium centre and steel teeth hald on with titanium pins
a friend of mine uses them and seems to like em


Posted by: rpmRMiam---------------------

So..... does the sprocket wear out first ruining the chain or does the chain strech and ruin the sprocket? You all prop answered this but how bout a recap?


Posted by: Zerotact---------------------

I know jaybird is extremely qualified to make is statements. He deals with chains and sprockets on a daily bassis in an industrial enviroment... But I'm claiming Iggnorance is bliss... You should see what an Aluminum talon sprocket looks like after a 2 hour hare scramble on my ATK... Maybe I was just masking a problem, but the steel ones appear to hold up better for me...

As far as the Ironman. they are made of tool steel, with hardened tips. The other ones just say they are made of steel... Tool Steel is a lot harder than what ever mystery steel the others are made out of.. And the cheap steel sprockets will not hold up as well as say an ironman, or the Ti coated sidewinder.


Posted by: Jaybird---------------------

Two things are the biggest contributors to sprocket wear, chain that is stretched and bad adjustment.

Yes, sand and other trail goodies can eat at a sprocket, but if there isn't lots of external forces eating at it, a sprocket will last as long as the chain isn't stretched, and adjusted properly.

Ironman sprockets are actually a chrome/moly steel. I don't think the tips are hardened. The hardness of the Ironman is consistant throughout the sprocket.
Actually, the lesser steel sprockets are preffered over a super hard type like Ironman. A regular steel sprocket will be case harnened, which allows for a very hard tooth surface, yet the softer core absorbs shock load.

This means that any energy transferred to the sprocket teeth will not be absorbed and will pass on to the other componenets. Like the chain, wheel bearings and coutershaft.

Ironman charges three times what an aluminum sprocket costs, and offers you a one year guarantee. This seems like a good deal, until you consider that you may have accelerated chain wear, as well as undue stress could possibly be put on the other components.

If you adjust properly, and measure your chain to know where it is always at, you can run any sprocket with good success. Superhard is a gimmick for those who, for what ever reason, have had an aluminum sprocket wear before it should.



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