A question about chains and sprockets

[.chris]

Yep, got their hands on some more high-grade steel. And there is now supposed to be an Auckland distributor.

KTM sprockets are cheap because all the adult bikes (singles) use the same rear sprockets. The LC4 fronts are unique but the SX & EXC bikes use a common front.

Chain Gang rears are slightly more expensive to run than KTM steel, IME: cost slightly more than double but last slightly less than double. But they are bling! bling! KTM fronts are very good - last nearly as well as Chain Gang but cost about half. Also Chain Gang's fronts are imported high-grade European stuff, not made by them. From memory the ironmans, stealths and chaingang all last roughly the same.

Given that KTM OEM steel is reasonably priced and lasts well, I wouldn't buy anything cheaper, and certainly wouldn't run a good chain on cheapo sprockets. Not only do you have to match the initial wear of all 3 components, for maximum life you also should match the quality so they all wear consistently.

At the moment the aussies are saying the DID 520 x-ring ATV chain is the hot ticket. That'll be my next one, and soon, as I'm up for a new set now.

PS if you reckoned your sprockets were good enough for another chain, then you can wait 3 weeks for the next set to arrive...

I agree with you on all points there, I was considering the cheaper sprockets, but maybe just waiting for the ktm's is better, would hate to ruin a good chain just to save $70.

My sprockets seem good enough to last a bit longer, but my chain I have my doubts about. I am away riding next weekend so I will just have to chance it (its ok I have AA Plus membership). I guess taking it easy on the throttle should help things (not that I am ever overly harsh).

I was thinking just buying a cheapest 520 chain (about $120) and running that till its bung, but with careful lubrication and gentle throttle work I might get that distance out of my old chain.

For reference, here are my chian/sprockets. I notice the front looks quite worn in the photo, that will be my eyes deceiving me I guess.

[bart]

I'd go the cheap chain, and flog those sprockets right out. For $120 chain and perhaps a $40 front sprocket later on, you should get at least 10000km. You're only running a 60hp, lightweight, dirtbike thing, mostly on constant throttle, not some 160hp, 300kmh sportsrocket, or lapping a mx track day in day out.

But I'm a rough bugger though.

[dino3310]

i replaced the lot and they looked like yours, but i got no slipper or cush drive, but i had the $$$ saved for a replacement, when i got no pingers i will run them right down, i only start to worry when i gotta adjust the chain after every ride

[warewolf]

For reference, here are my chian/sprockets. I notice the front looks quite worn in the photo, that will be my eyes deceiving me I guess.

Yeah, I certainly wouldn't call that "still look pretty good". They're all fcuked... replace as a set. Keep riding it for a few weeks to make sure they're fcuked, and/or get the utmost last bit out of them, if you are tight like bart.

The front sprocket is almost hooked, and has the tell-tale flat-bottomed glacial valley look about it, should be a nice sine wave. It's on it's last legs. Also, check the chamfer visible on one side... it's absence from the other side shows the thickness of tooth worn away.

The chain is stretched, close to wear limit which is approx 2/3 rear teeth showing when pulled like you have in the photo - how does it measure? Plus it has heaps of stiff links.

The rear sprocket may be the best of the lot but hard to tell from the photo. Some of the teeth look quite pointed instead of fat & rounded - missing the chamfer.

80/20 rule: 80% of the wear occurs in the last 20% of the life.

[MSTRS:Me]

My sprockets seem good enough to last a bit longer...

Um...in a word...NO.
The whole lot has had it. They will last a little while as they are, but replace together. Front sprocket in particular will destroy a new chain within a couple of thousand kms - if you are lucky. And looking at the link alignments on the chain...

[.chris]

Um...in a word...NO.
The whole lot has had it. They will last a little while as they are, but replace together. Front sprocket in particular will destroy a new chain within a couple of thousand kms - if you are lucky. And looking at the link alignments on the chain...

Yep, just ordered replacements for the sprockets. Going to source a chain locally due to better prices/more range than my ktm dealer can offer.
I shall just have go easy on her for the next 3 weeks till they arrive, only one weekend planned riding anyway, only some beach riding.

Thanks everyone for your help, I feel well informed and made the right decision.

[bart]

if you are tight like bart.

Ahhhhhhhhhh. I just 'got' it. You're all KTM riders, so you've got to have everything all shiny and new.

Seriously though, they look pretty shagged. I picked up a chain for $79 so would be absolutly stoked to see 10000km even with new sprockets. Being a 525 on the DR, I thought it was worth a gamble. With the 520 chain on a KTM 690, I'd be buying quality stuff also.

[Taz]

I agree. Those sprockets are shagged.

[pampa]

this is what happens if you try to replace all set together and not as recommended the front more than once per rear+chain



Weirdly enough bike didn't have more torque ... I was told I would get but extra hp per tooth drop ... so
15t => 58
9=> should be close to 100 but it didn't happen

[MSTRS:Me]

For a sprocket to get like that, the chain was long gone too...
Dropping a tooth or two on the front (or raising on the rear) does not give you more torque or HP. It does, however, drop the gearing. Which will give a better rate of acceleration, albeit a lower top speed.