I have a 2020 commencal meta which is great. Geometry already pretty good but want to slacken the head angle from 66.5 probably just to 64.5 with a 1 degree headset.
However just so much variation on what people say this does to the overall geomotetry. Can't seem to get an answer on what this will do to the reach? Ideally wouldn't want to make it much shorter.
The only thread I found on it seemed to have about 10 completely different answers from no effect, shorter reach and longer reach. Has a consensus now been reached?
It’ll drop your front end slightly which increases reach, but I’ll also angle the stem and bar back towards you slightly which decreases reach.
When I did this to my old jeffsy I used a 1.5 degree headset and also increased my fork travel by 10mm which resulted in similar numbers all around and a few mm reduction in reach.
Plug your geometry numbers into this and have a play to figure it out for your frame.
Basic trigonometry will help answer this.
It depends on how much higher your grips are than the top of the headset (I.E. where the steerer emerges from the frame). Ideally measured along the axis of the steerer.
Using that info and some trig you can work out how far rearwards (and up/down) your grips will move. From a 1 deg change I suspect such a small amount it won’t matter. And could be adjusted back again by rolling your bars forwards a touch / fitting a slightly longer stem.
Don't worry about it, is my view. Slacker head angle means grips will "move" a tiny amount both down and rearwards (in relation to the frame). How much they move depends on how far away from the top of the headtube they are currently (i.e a slammed stem and flat bar and you'd barely even measure the difference but (exaggerates) 10cm of spacers and then a riser bar and it'd be much more obvious Easily returnable to original relative positions with stem/spacers (or maybe just rotating a riser bar a little) if you feel that's important
Front centre will be longer by a less-tiny but still small amount. Presumably this is part of what you're after
Also 66.5 - 64.5 does not equal 1 degree...
It’s negligible. Especially when compared to how much better the bike will descend (I’ve yet to ride a bike that wasn’t improved by and angleset).
