Hey there guys, I recently noticed my nearly new sprockets are wearing super aggressively and oddly and I’m hoping you guys might be able to share some insight and knowledge as to why. The bike is a new to me 2019 450 xcf. I bought it with 25 hrs on it and did a full Cush drive warp 9 sumo conversion around the 28hr mark. With that I put on a new standard non o ring ktm 520 chain and 14t countershaft sprocket. The rear wheel came with a 45t warp 9 sprocket already installed. The kit also came with spacers for the wheels already as well. It was a pain to squeeze the rear wheel in there but got the kit installed and everything was seemingly good with it. That being said I didn’t mess with sag at all, and gave the chain the good ol 3 finger slack measurement and called it good. I have put maybe 10 hours on this setup total, and Lately I noticed quite a bit of noise from the driveline while riding and upon further inspection noticed my sprockets are worn to shit. The chain seems fine though? The chain was if anything loose, so I don’t suspect a tight chain to be the culprit although I did neglect setting sag so maybe that could be a variable? The wear pictured is only on the outside of the rear sprocket, and similar deep wear on both sides of the countershaft sprocket. Any info would be greatly appreciated, I’m in the process of switching back to factory dirt setup with the factory countershaft sprocket and chain, in hopes of isolating this issue to the sump setup and can hopefully narrow it down from there. The countershaft splines don’t show any wear as I probably caught the problem earlyish. Again any insight would be huge as I’m a bit of a dummy. Thanks!!
IMO doesn't look too bad, maybe a little more wear than I would expect for 10h, but I also haven't used a Warp 9 sprocket so I don't know what their durability looks like.
Sumo wheels are smaller than stock, and the 45t is smaller than stock, also probably doing more distance than a dirt bike, so the sprocket would take more wear than the dirt set up.
If it was me I'd stick one of those cheap heavy steel sprockets on to get more time between changing. DirtTricks makes some trick looking steel sprockets that last a long time too.
450”s eat aluminum sprckets & standards chains up fast….steel rear & quality xring chain last long time…I run RK mxgbu & supersprox rears… even in sand I get solid 50hrs out of this setup…
It looks like your chain guide is bent in, or something stuck in your chain guide and is wearing into the face of the sprocket
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Same here, RK MXU and JT steel sprockets.
+50h and only minor adjustment needed. It comes with clip type connection link which I change once or twice
Running steel won’t add anymore wear and tear to the countershaft? How are you ensuring that the rear wheel is aligned properly? I was assuming the axle blocks would get me close enough to call good but seems like that may not be the case? Sorry for the dumb questions lol thanks fellas 👍
Here’s a couple pics of the front sprocket. Still can’t wrap my head around the idea of things being misaligned and it only effecting one side of the rear sprocket and both sides of the counter shaft sprocket. Seems like it would only wear on the same side of each sprocket if things are out of whack? Granted I’m a idiot and know nothing so maybe I’m way off lol.
The chain and rear sprocket are 520 like the counter shaft sprocket?
Yessir unless I somehow totally botched it lol
I can't see your chain guide so not positive but the hub may not have the same spacing as stock causing a side load on your drive line. Run a piece of string from the center of the top tooth on the counter sprocket to the center of the rear most tooth on the rear and see if you can detect any angle.
^This. You mentioned the kit came with spacers and it was hard to squeeze the wheel into the swingarm. Is the rear wheel straight? Is the chainline straight from the rear sprocket to the countershaft?
Also: is the sprocket straight? A wobbly one would explain wear on both sides of the countershaft sprocket. You'd see that in your chain guide, for sure.
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