Originally Posted by
Cyclocujo
The stem on the bike now is 85mm but it's a 25.4 so ill be looking for a 31.8 stem cuz the bar I'm planning on using is a 31.8 and 685mm long.
Huh. From a steering/handling perspective, 85mm is a pretty short stem for a bar as narrow as 560mm. Sounds like a very "twitchy" ride to me.
Going from a 560 to 685mm bar (which is a pretty huge jump), I would normally think going about 30-40mm shorter on the stem would be a good starting point, but in this case that would be a ~50mm stem which mighy be a tad short for a 685 width bar. Or maybe not.
If the fit of your current setup feels good to you, I would start with a 60 mm stem and see how it feels. Thos is erring slighly on the long side, but will be more likely to work out if you end up cutting the bars down some.
In the end, a change this large may take some fine tuning in stem length and rise.