I've had an IRO Mark V for about 3 months now. Great bike.
My only complaint is that there is a very annoying buzzing/clicking sound coming from around my bottom bracket/chainring area. It has always been there since I got the bike, and I'm not sure if it has gotten worse or just slowly started progressively pissing me off.
I took it to an LBS, told them what was going on and asked them to check out my bb and cranks. They did and said that the sound was normal for a single speed. I don't believe that. I have friends with whisper quiet bikes that are much cheaper than mine. After they checked it out, they tightened my chain. Like, there was no slack in there.
On the ride home it was even noisier than before, and when I was going slow(like slowing up or starting off at a light) I could feel waht seemed to be the teeth on the chainring slipping into the chain. Later when I got off the bike and was just walking it with my hand on the saddle I could still feel that slight bumping. I loosened my chain, and solved that problem. Its still makes that sound.
I went on a pretty intense ride yesterday(Got up to 30mph for my first time on a flat) and several times when I was just pedaling hard as **** the chain sounded really bad.
I have the stock bb, chainring, chain, and cranks from IRO. I've routinely greased the chain.
Do you guys have any ideas? I was thinking about maybe trying to borrow a different chain and cranks set, switching them out with mine, to see if either of those could be the problem. I looked at sheldon browns noise guide and none of that stuff sounded like what was happening with my bike.
I know when something doesnt sound right, and I am almost ocd about mechanical noises. Any help would be greatly appreciated.