Front sprocket and SES pulley replacement

[tallpaul]

I am replacing these two sprockets on my 2&1/2 year old Haibike Full Seven.
I have 5000 miles on it, almost all on pavement, very little dirt trail rides.
Ride mostly relatively flat terrain, weigh 200lbs., never in the rain, and mostly in eco or tour.

Religiously cleaned and oiled the chain and drivetrain components.
Replaced chains (about every 1200 miles or so) with KMC bike chains.
Replaced cassette at around 3k miles.
Upgraded the SES bearing at around 2k miles with ceramic bearing.
The front sprocket and SES sprocket are quite heavy duty, especially compared to the Shimano cassette.
And quite expensive (well over $200 for the two) and not easy to obtain.

My question is if this is to be expected?

 

[Ravi Kempaiah]

I am replacing these two sprockets on my 2&1/2 year old Haibike Full Seven.
I have 5000 miles on it, almost all on pavement, very little dirt trail rides.

What is prompting you to replace those items?
Noise or reduced performance?

 

[tallpaul]

Replaced a chain about 6 months ago and it was noisier then the one it replaced.
But it eventually "stretched in" I assume and ran quieter.
Got about 1200 miles on it, now stretched out. New chain makes a racket engaging front sprocket under load. I put the old chain back and it was quiet.
I think that the front sprocket must be worn in such a way as then the new tighter chain has to "bang" into position when under load.
What surprises me is that both of these sprocket are hefty cast stainless steel and don't particularly look worn.
You can slightly feel a vibration synced to noise in the handlebars.
I'm told that aluminum frames carry vibrations very well.
Hope my assessment is right and the new sprockets will fit the new chain and quiet it all down.

 

[bglidin]

TallPaul
where did you source the ses ceramic bearings and how have they held up ?

 

[tallpaul]

Got the bearing at a local bike shop. I don't think it held up any better then the original steel bearing from Haibike.
The refitting of the SES and chainwheel sprockets did the job, all quiet again and hopefully for the next 5000 miles or whatever!