Track/Fixed Gear Chain Tension??

Hi,

OK here it goes.

I am used to riding my track bike with a rather high tension on the chain. I have recently built up a bicycle for a friend who couldn't get on with it. Well that was until I loosened the chain tension a little.

He stated that it seemed tough to pedal at first, but after adjusting the chain it seemed to be easier. In the middle of the chain, between front and rear it probably moves an inch up and down in total.

Can anyone explain this to me or if there is a correct way to have the chain tension?

Many thanks in advance.

If the chain is super tight the drivetrain will wear prematurely if not have the potential to bind up due to slight out-of-roundness in the rings. I always found that a little bit of slack (an inch is fine!) is not a problem.

Things will be quieter/run more smoothly. If you are riding a conversion make sure that you have proper track nuts--you don't want a Q/R slipping.

I've also used MKS tensioners, and they are neat little doo-dads, but not really necessary in my experience.

I always run my fixed chain a little on the slack side. I don't really like that little bit of back-play you get in the pedals from a slack chain, but I don't like the grinding noise it makes if it's too tight either. So I go for looser over tighter.

Looking at the track bikes in the Olympics and Paralypics, it looks like the pros don't run theirs massively tight anyway. I've seen more than a few chains with a bit of droop on them.

General wisdom is that about an inch total deflection is what is required. Too tight and you get the grinding and premature wear (of cogs and bearings) already mentioned, too slack and you risk unshipping the chain on every bump in the road.

The classic way to check your tension is hold the bike on its side spin the cranks and shake the bike up and down. If you can't make the chain come off then it's not too slack. You can slacken the chain off until it comes off when you do the aforementioned test then tighten it a bit.

I remember when we used to go to six day events being surprised how slack the track riders had their chains. Until then I always ran mine too tight I think.