new chain, old chainring

Question
Hi Tad, thanks for your concern with the campy hub and shimano hub/wheel. Well, that issue remains and sits on the sidelines, until I put them back on ebay which is how i acquired them. There apparently is no 'cheap' fix for that dilemma.

 I prepare to leave tomorrow for Burnaby, BC and their indoor wooden 200m track. My wife has a conference in Seattle for the weekend and since I need 'track' time I felt it worthwhile to take some time to take the 7 hour drive to Seattle with her and then the subsequent 3 hours up to Vancouver to land at the track, non weather permitting. My ala mater, SImon Fraser University happens to be within a stones throw of their indoor track. The banks are steep at 47 degrees, I've raced though years ago on 43 degrees at Alpenrose where I won the North American Championship 5 mile events. I may very well be a 'legend in my own mind' so to speak trying it all again  but I'm going to give it a go regardless this Friday and Saturday when they have some open time for training. It took getting a UCI lecense and my 'credentials'  to allow me on their track.  I thought I had it all together, order this and that until i was ready to hurl with it all, putting together a Dolan frame from scratch having bought one on ebay from Carytown Va a few weeks ago.But i had new handlebars, new track wheels, bb, pedals, chain, stem, seat, seatpost..blah balh. Alas, when I finally it all together, all was well until I put the chain on this afternoon it scraped and moaned and groan upon turning the crank...add a bit of oil and no change. Crap!!!!!  I can only surmise, it's a new chain with a 43 year old campy 50t chainring. I figured though that happens on small cogs on a cassette, never had it happen on a large ring like a chainwheel before. The chainriing 'looks' fine but only besides that I can only guess the line of drive front to back is off with the bottom bracket/chainring and rear sprocket. Even that looks good to me. But my 'old' eyes aren't what today's mechanics are. Regardless, discouraging.  Bottom line, i just want to ride and have the mechanic part behind me. Any other ideas??? I'll take it to a shop in Seattle. Know any you recommend? I'll see what someone else thinks. On the other side ot things, my Schwinn Paramount track bike i'll probably sell now  has had two go's at straightening the front forks, one in Seattle, one in Sandpoint, only to have front wheels 'not fit' them when i get home both times. I think the forks need a 'retainer', like teeth do after an orthodontist finishes brace work, to maintain the 'new shape' taken on.....anyway, Tad..thanks for listening...smiles on your week :)

Answer
Jim,

That is so cool, you getting on the track again! When I was living and racing in Minneapolis many years ago (Same year Lemond won the Tour and the World Championship) they built a track in a northern suburb. They did have open days for people to come out and try it, but I was either working or just plan lacked the courage. I did build myself up a track bike later only because I got a really good deal on a Cannondale frame. I did a couple of road training rides on it - what a work out! - and I used to commute on it. I got pretty good at "skip stopping."

I am wondering if the old chainring is just slightly wider than the new chain? I wouldn't think they changed the width or pitch on fixie stuff but you never know. I will see if I can find that answer for you. My only other thought is the chain line and that sounds more reasonable. Take a straightedge between the cog and the ring and see if it lines up.

One more thought... could your chain tension be too high? If the cog and ring are not in perfect alignment and the chain tension is high I can see that the the chain would be "popping" as it left the ring. You might want to try backing off on the tension just a bit. If I recall correctly there should be about 1/4 to 1/2 inch of deflection in the chain.

So I would do the reverse order of things I have thought of if the bike was in my stand: I would check the chain tension and play with that a bit; If that didn't do it I would then check the alignment; If that didn't work I would replace the chainring. And if that didn't work I would tell the guy that he is too old and why does he want to mess around on the oval anyway! ;)

Good luck! I think you will find it is something very simple and then you just have to worry about the banking! I do have to say I am a bit envious so go do a couple of laps for me!

Have some fun!

Tad