How slack is too slack?

It’s starting at 67deg HA but I think it would end up at about 64.5deg. Too slack and a ruined ride?

What does STW think? Maybe 65.5 would be the sweet spot?

Nah, go straight to the -2deg headset.

You might even decide to supplement it with an offset bushing later to go a touch slacker still.

A -2 deg headset slackens the headtube vs the frame by 2 deg but rotates the whole bike forwards, steepening everything by about 0.5 deg. The 10mm longer fork will slacken it by a bit under half a degree, less still at sag. You'll end up slightly above 65 deg head angle (but it could be about half a degree more or less depending on the manufacturing tolerances). I doubt you'll find it too slack.

Adding fork travel and slacking the head tube together will keep most of your geometry about the same as it was before, just with a slacker head angle. The longer fork raises the front end, then the slacker head angle drops it again.

Just do it, I don’t think you’ll regret it at all and if you do then you can always put the original headset back in.

Shand Launches Ioma hard tail with 58 degree head angle....

64.5 is about average these days tbh, my 3 year old bike with 65.5 (thanks to an extra 10mm on the fork) feels dated!

I reckon my Flaremax is slacker (65 deg before a -2 headset added).

It'll also steepen your seat tube so that's a positive too.

https://www.pinkbike.com/news/shand-launches-ioma-hardtail-with-58-degree-head-angle.html

*60 degree, but supplies a +/- 2 degree angle adjust headset with it.

I've just gone slacker on my Swarf Contour. Originally 66.5 HA. 2deg slackset and running a 150mm fork (geometry figures are for a 130mm), so that all brings it down to around 64-64.5°.

Runs very nicely like that, a subtle but noticeable improvement.

Mt Starling's below 64 degrees and is great. You'll be fine.

Trail bike with around 64-65 degrees works fine for me. Had a Bird Aether 7 which is similar ish (but slacker) to the T130. Rear 4 bar suspension with 130mm travel and I was running a 150mm fork on it. The steering didn’t flip flop or anything like that - it was just confidence inspiring on the steep stuff and fine everywhere else.

Now on a sentinel with 160 front / 150 rear travel that has a 63.6 degree head angle. It still feels natural / great to ride.

I think the majority of us having been riding round on bikes that are steeper / shorter than ideal for years.

You'll be totes fine. Just on the road to getting to the righteous 63°

Cool, well you’ve convinced me - I’ll be giving it a shot

That Shand does seem toooooo slack surely?

My mountain bikes
Geometron g13- 64.2 +20mm fork +1 offset bushings so about 64?

Hello Dave -62 degrees +10mm fork travel so about 61?

Orange clockwork.67 degrees. -2 angle set, stock 27'7 fork length 506mm. Run with 26" 150mm fork at 520mm (I think) axel to crown. so about 64 degrees?

They are all fun. They all go up and down just fine

I’ve never ridden a bike that wasn’t inporoved by slackening the head angle with either a slackest or offset bushings (or both). Go for it. If you don’t like it after a few months just take it out and sell it.

At first I thought that if it was me I’d run a shorter fork on that Shand but having seen the BB drop is already 70mm that might make it a bit low, mine is 65mm and low enough (although I’ve never had a pedal strike with my 175mm cranks I’d still swap to 165mm for preference). I think too low a BB and you struggle to pop the front over things and manual.

I donmt think it’s the slack head angle that makes modern hardtails look ‘odd’/wrong, it’s the really steep seat tubes (although I understand why we have them regarding reach/pedalling, etc) that make them look ‘odd’.

I donmt think it’s the slack head angle that makes modern hardtails look ‘odd’/wrong, it’s the really steep seat tubes (although I understand why we have them regarding reach/pedalling, etc) that make them look ‘odd’.

slack head angles combined with low top tubes - that are lower than the seat stays - kind of give the impression of taken a hard landing to flat and buckled.

the inverse is the older bikes where the headtube was steeper than the seat tube. looks like theve been run into a wall.

Do it.

It's more a case of (or it was for me!) where you notice a difference. Bikes down to about 67 degrees felt quite similar to steeper angled bikes. When you get below 66-65.5 they feel better/safer on very steep trails and when counter steering drifts. It's a subtle, not drastic difference, unless you have gone from one extreme to the other and back to back tested it on specific terrain which highlights the difference!