Caaah

Ok, my Curve D3 finally decided to make a weird noise. Starting in the middle of last week--I have about 300 miles on this bike--I started to get this extra rattling. What's weird is it only happens when I'm in 2nd gear (direct drive) while coasting AND only while the chain side crank is pointing at 12 o'clock. I tried to figure out what the noise was while off the bike, but its not obvious to me. Any ideas??

EvilV

Second gear is usually the quietest of the gears so there is something amiss here.

Check that the hub is properly tight in the frame and that the rear wheel is aligned properly. From what I've read there can be problems in keeping the rear wheel properly aligned as pressure from the chain can can pull the wheel out of alignment.

Is the axle bent?

If that's ok, try and put the bike on a repair stand and turn the pedals in the affected gear. If you haven't got access to a stand, upturn the bike on a garden table outside and do the same. Spin the back wheel up with the pedals and listen carefully to the hub, while looking at the rear sprocket to see that all looks correct there. If the noise is coming from inside the hub, try adjusting the cable according to the instructions to be found online.

I adjust my srf3 by putting the handlebar changer in third gear and then adjusting the gear cable until it is just VERY SLIGHTLY slack - only a touch though. Then I try the bike out and make sure I can still get first gear. If I can't, I tighten the cable bit by bit until I can and then check again that I can get third. When all gears are reliably selectable, I tighten the cable lock nut.

The only time I've had a funny noise come from inside the hub was when I had the cone adjustment wrong. This can alter gear alignment. From your description though, I can't imagine it could be this.

There are good descriptions online of how to adjust the cones - but only mess with this IF YOU HAVE VERY GOOD REASON to suspect that is the problem. If you rock the rear wheel side to side, there should be only just a touch of lateral play. You can get internal noise if there is too much or too little because the gears can run out of line. This is a very destructive situation for those tiny teeth on the sun and planet gears and the gear ring.

Caaah

Thank you! I'll try all your suggestions when I get home tonight.

Edit: Oh, I should mention--a day or two before I heard the noise, I moved the grip shifter over on the bars to make room for new grips. Could that have anything to do with it? I thought the cable adjustment for the hub was down near the wheel. Or is one of the screws on the grip shifter the adjustment? If that's the case I bet I have it adjusted wrong.

makeinu

That's probably it. Since moving the shifter probably changed the taughtness of the cable, you probably want to readjust the cable at the wheel.

Caaah

Thanks makeinu.

Is the adjustment under the black plastic cover on the right hand side? I didn't want to pop it off without asking first.

It looks like this: