Sean21

I replaced my chain and now it won't go down the gears, is this indicative of worn chainring and rear free wheel?

oldbobcat

What do you mean by "go down the gears?" Did it used to "go down the gears" before you replaced the chain?

ClydeClydeson

Generally the lateral movement (shifting) of the chain is not greatly affected by replacing the chain. SHifting might be a little faster or slower, but if you could get to all gears with the old chain, you should be able to get to all gears with the new chain. If the chain isn't able to move across all gears the problem is likely with derailleur adjustment. You'd have to give more details about what exactly is or isn't happening with your shifting for anyone to give a helpful answer.

The indicator that your cogs or chainrings are worn is that the new chain skips under load - sometimes violently. If you can pedal at full strength in each gear without the new chain skipping then the cogs and chainrings are not overly worn.

Bill Kapaun

Did you route the chain correctly through the RDER?
Look at another bike to compare.

Sean21

I was having problems shifting from larger cogs to smaller cogs on my 21 speed freewheel and chainring while under load. I've changed the chain, bb and cables and housing. The shifting is nice going from small cogs to larger cogs, the problem is coming back down they seem to be sticking, not smoothly shifting back to smaller cogs. If I take tension off by the barely adjuster, it doesn't improve and just messes up how smoothly the shift is from small to large. This is without pressure and is basically the same problem I was having before. Because shifts good from small to big I assumed might be worn cogs? Having same problem in the front. I mistakenly put 118mm bb, should be 115, could this be an issue? I would think either worn gears, bad DR'S, not attaching correctly at pinch bolt, or STI shifters or not working well with altus DR'S, STI's are not original.
the chain appears to be routed correctly. Pedals ok in gear.
I

imakecircles

Sounds like it shifts fine when you're pulling the cable (shifting from smaller to bigger), but not when the derailleur is returning, which means that perhaps the derailleur return spring has lost its tension or there is gum in the works somewhere. Most often this is caused by friction in the cable/housing, especially if they have not been replaced recently. Try removing the chain and unfastening the derailleur cables to see if the derailleurs return to where they should without anything holding them back. If they do, you have friction in cables/housing and they should be replaced. If they don't return all the way to their 0 position, then try cleaning/flushing the derailleur mechanisms out with WD-40 or similar.

Sean21

​​​​​​The cables and housing were replaced and the derailleurs and shifters have been cleaned.

Sean21

​​​​​​When I shift to smaller gears there is immediate derailleur movement, It's just not smooth or quick, it's out of one cog, then for a moment it's on top of the cog then down.

Digger Goreman

That sounds like poor derailleur adjustment.