Chain / sprockets opinion

[426 NOOB]

I have searched endlessly on this subject and I know i want a regina orn6 chain. For front sprocket i was looking at the moose chromoly and the pro taper chromoly. Has anybody had experience with either of these?

Also I would like an ironman rear but it has to be a 52 tooth and msr does not have one in that size:banghead:. Does anybody carry them in 52? Also I have heard that ironmans are now made with a full ring in the sprocket center, instead of small tabs where the bolts are, but msr does not show them like this. And last but not least, has anybody had any problems with the full inner ring ironmans (such as bending or breaking like rumors said the old style did)? Any input apprecated.

[Jim813]

Also I have heard that ironmans are now made with a full ring in the sprocket center, instead of small tabs where the bolts are, but msr does not show them like this. And last but not least, has anybody had any problems with the full inner ring ironmans (such as bending or breaking like rumors said the old style did)? Any input apprecated.

I have never seen any of the old style have any issues as far as bending or breaking. But, Ironman does now make their rear sprocket with a inner ring. But, the inner ring does not contact the hub. Here is a picture:

Personally, Ironman only added the ring to get rid of any doubt about the sprocket having strength issues.

[grayracer513]

I have never seen any of the old style have any issues as far as bending or breaking.

I have. Not breaking, but bending, and thereby breaking the hub. Almost always had to do with an excessively tight chain, though.

https://www.thumpertalk.com/forum/showpost.php?p=4584448&postcount=8

[ThumperKid250F]

i love ironman sprockets. i had a 52 tooth ( oldstyle ) ironman on my 07 yz 250smoker and i bent it in half and riped my chainguide off .. no fault on iron but it was just some crazy thing that happend racing in the woods.. my chainguide hit a stump and ripped off my chainguid and bending the sprocket in the process

[426 NOOB]

I have never seen any of the old style have any issues as far as bending or breaking. But, Ironman does now make their rear sprocket with a inner ring. But, the inner ring does not contact the hub. Here is a picture:

Personally, Ironman only added the ring to get rid of any doubt about the sprocket having strength issues.

Cool, thanks for the pic.

and also thanks for the bit of info on the tight chain causing most of the bending of the sprocket, i will be maintaining my new sprockets and chain very meticulously.

[426 NOOB]

So does anybody know of a decent dealer that carries these in 52 tooth? I have looked on my local dealers website and they can only get the msr repackaged ones and cannot get them in 52 only 51.

[ThumperKid250F]

So does anybody know of a decent dealer that carries these in 52 tooth? I have looked on my local dealers website and they can only get the msr repackaged ones and cannot get them in 52 only 51.

i orderd mine online. just type in iron man sprockets in google and it will just list it

[426 NOOB]

i orderd mine online. just type in iron man sprockets in google and it will just list it

ok will do.

[426 NOOB]

so does anybody have any experience with the pro taper and moose front chromoly sprockets?

[grayracer513]

I've used both Moose and PT fronts. The Moose didn't really impress me on the 250F I installed it on, while the PT is holding up quite well on the YZ450.

[426 NOOB]

I've used both Moose and PT fronts. The Moose didn't really impress me on the 250F I installed it on, while the PT is holding up quite well on the YZ450.

awesome, pro-taper it is. thanks to all who helped.

[Polar_Bus]

so does anybody have any experience with the pro taper and moose front chromoly sprockets?

One of the aspects of "sprocket life" that i've come to learn over the years is that it's not the lack of quality of the sprocket that prematurely wears out sprockets, but the lack of quality within the chain that trashes sprockets IMO. I have traditional, inexpensive Sunstar steel (front) and aluminum (rear) sprockets, with a top quality Regina ORN gold chain on my KX500 and it's been on there for almost 4 years with normal weekend riding, and the sprockets are only showing a very minimal amount of wear. I'm very impressed thus far. (just my $.02)

[Jim813]

I have. Not breaking, but bending, and thereby breaking the hub. Almost always had to do with an excessively tight chain, though.

https://www.thumpertalk.com/forum/showpost.php?p=4584448&postcount=8

I stand corrected. I have yet to personally see one fail when a correct maintenance schedule is applied.

[grayracer513]

One of the aspects of "sprocket life" that i've come to learn over the years is that it's not the lack of quality of the sprocket that prematurely wears out sprockets, but the lack of quality within the chain that trashes sprockets IMO. I have traditional, inexpensive Sunstar steel (front) and aluminum (rear) sprockets, with a top quality Regina ORN gold chain on my KX500 and it's been on there for almost 4 years with normal weekend riding, and the sprockets are only showing a very minimal amount of wear. I'm very impressed thus far. (just my $.02)

This is absolutely correct. As witness to it, I give you the OEM 49 tooth rear on my own '06, which is still there after over two years (there were only two rides on the bike up to Sept. '07, so I'm counting from there). That whole time it was run with a Regina ORN6, which has just now got to the point where it will need to be replaced.

The key is the wear within the chain, just as said above. When the chain is new, or in near new condition, the drive loads are distributed fairly equally over the entire contact area of the sprocket. About 55% of the sprocket teeth, 27 or so for a 49T cog, share this load, and the force of it on any one tooth is reduced by that amount because of it. As the chain wears at the pins and bushings, the pitch, the length between pins and rollers, gets longer. As this progresses, the chain no longer bears equally on all teeth. Soon, only the foremost tooth on the top of the sprocket is carrying the entire force of the drive load all by itself, because the distance back to the next roller is greater than the distance to the next tooth. This means each tooth is now carrying 27 times as much load as it's supposed to. Why wouldn't it wear?

Yamaha states that the chain needs replacement when it has "stretched" (stretch is actually cumulative wear) 2%. That's over .012" at each pin, and I think it's excessive, but it should definitely be replaced if it gets that long. I replace at no more than 1.5%.

And by using a truly wear resistant chain like the ORN6, I can run good quality, lightweight, relatively inexpensive sprockets like the Tag or AFAM units instead of pricey stainless steel ones.