40mm vs 35mm stem: what difference, if any, will I notice?

I’m experimenting with stem length. Currently I’ve got a 35mm stem, which feels good, however I sometimes feel that I lose front end grip on flatter technical sections.

I’ve tried a 50mm stem, which just became a little uncomfortable on longer rides as I felt that I was putting too much weight through my arms when sat peddling.

I quite like the idea of putting a (matchy matchy) 40mm stem on. Mostly because I want to colour match, but also because I wonder if it’ll be a good compromise between the two lengths.

My question is, am I really likely to notice a 5mm difference having an effect on comfort and bike balance?

Only one way to find out is try it, this video is a good summary of the differences:

I’ve been through the same process of 35, 40, 45, they’re all fine, non of them feel lethal, 35 is fun and makes the bike easy to manual, charge on steep stuff, 45 feels nice and planted like you can just stand up in the middle of the bike and let the bike do it’s thing.

I find more difference in stem height, for steeper tracks around Hebden I like the stem a bit higher, for flatter flowier trails it’s nice to drop it down a bit so you can weight both wheels easily for flat corners.

I’ve tried 31/35/40 on the same bike, and, yes, they all felt different… but you just adapt to whatever you have on there.

Thanks guys.

Interesting that like the video says, I also noticed a bit of oversteer with the 50mm stem. I didn’t realise it was due to the stem length though.

I think that if you have asked on here AND watched one video, then you have definitely justified a matchy matchy 40mm stem. Almost impossible to avoid it now. Best get it done asap. In fact as you already know what you want you have saved money by not buying a cheap one ‘just to check’ first before you get the matchy one.

Thank you. This is the answer I was looking for.

It’s more than a 10% difference, it’s really worth trying to see what suits you, sir. I recently built up a new bike with a 44mm offset Zeb and couldn’t get on with it at all. Soon as I fitted an older fork with 51mm offset it all came together and the bike rode as I wanted it to.

I went from 10mm to 35mm and found a big difference. Pulled me right forward.

Soon as I fitted an older fork with 51mm offset it all came together and the bike rode as I wanted it to.

Was the older fork also shorter axle to crown?

No, same length

*reaches for tape measure to double check what 5mm looks like…*

I crashed on my first ride on my Switch9er. Front wheel washout on a rocky flat turn. Swapped it for a 50mm and didn’t ever crash (in that manner) again.

More importantly though is that you will notice if it’s matchy-matchy. So will everyone else. They’ll think you have impeccable taste and illogically transfer that to their view of how you ride, thus more than justifying the purchase. In fact you’d be barking mad to not buy a new stem.

You can roll your bars forwards/back to get +/- 5mm reach.

It’s not about the bike

This is what you need. Evert trail covered.

You can roll your bars forwards/back to get +/- 5mm reach.

whilst absolutely true I’ve never liked the feel of bars that are overly rolled forwards.

Me neither. Nor too far back.

For me, bar roll has always been about getting the bar ends at the right angle for my hands to sit on them comfortably.