Disalligned cassette/chainrings by wheel replacement

[Robert Arnold]

I swapped my old wheels for a Vision team 35 comp sl on my relatively old roadbike Trek road series 370 (1995ish). This has caused the cassette and front chainrings to be disalligned; in the largest three rear chainrings in combination with the smallest front ring, the chain falls of now often. I already used an spaces because the bike is 8 speed. Do I need more spacers or is there some other solution?

[Jesper]

(10-27-2021, 06:18 AM)Robert Arnold Wrote:  I swapped my old wheels for a Vision team 35 comp sl on my relatively old roadbike Trek road series 370 (1995ish). This has caused the cassette and front chainrings to be disalligned; in the largest three rear chainrings in combination with the smallest front ring, the chain falls of now often. I already used an spaces because the bike is 8 speed. Do I need more spacers or is there some other solution?

This would depend on where you want your chainline to be in relation to the cassette. Also, depending on the gearing you may have to adjust the tensioning of the rear derailleur and/or "B" pivot screw setting. I would first verify the hi/lo limit screw settings for the rear derailleur. For my personal use bikes I tend to have the chainline set-up for my primary gear usage rather than a traditional set-up. You may have to change the bottom bracket spindle length. I am not as familiar with 'newer' systems so it might be advisable to wait for some more detail oriented advice regarding your issue from those more experienced in this matter.

[jeffg]

Assuming the chain is falling off of the small chain ring when the rear derailleur is in the three largest sprockets on the cassette, a shorter spindle will be needed. Doing so will then cause issues when the derailleur is in the smallest sprockets on the cassette. Mainly heavy chain rub on the front derailleur. As Jasper noted, set the chain line up to the gears you use most often.