Angle headset, slacker lower longer

Kerplunk

Likes Bikes and Dirt
Hi all,
I want to have a go at slackening out my trail bike, it’s a 29er with a ~ 68 degree ha (2016 intense spider 29). Looking at works headset (zs/ec tapered). Just wondering how far should I go with it, thinking -1 so the bike isn’t that far out of spec. I like how it handles now just a speed the front end seems a bit more twitchy compared to the rear (445mm cs) which is mega stable. This is a do it all FS bike with a 130 fox 34 on the front.. I ride Bright to the yarra trails on it. I don’t hit anything massive but like dark blue/light black trails mostly.. Have an xc hardtail for pedal fest duties. Just want to see how much more I can get out of the bike without the need to upgrade. -1, -1.5 or 2?
 

rstim

Likes Dirt
What about a set of offset bushings for the shock should be able to get 1 degree depending on pivot size.
 

Kerplunk

Likes Bikes and Dirt
What about a set of offset bushings for the shock should be able to get 1 degree depending on pivot size.
Tbh I prefer the geo changes from the angle headset, steeper seat angle/not as low etc. It also appears to lengthen the front centre which will balance out the longer back end..
Correct me if I am wrong?
 

yuley95

soft-arse Yuley is on the lifts again
Tbh I prefer the geo changes from the angle headset, steeper seat angle/not as low etc. It also appears to lengthen the front centre which will balance out the longer back end..
Correct me if I am wrong?
Slackening our the head angle will also slacken seat angle. And it will slightly shorten the distance to you bars as they will be angled back towards you slightly. At just 1 degree you may not notice the change in reach much though.

What you are suggesting is worth trying but the other (more expensive) option is a longer fork. It will slacken the head angle and give you some extra squish.

I’m not sure what fork you are on now but a burlier fork can feel like a big improvement through rough, rocky and rooty terrain too as it resists twisting and deflecting.
 

kten

understands stuff moorey doesn't
Slackening our the head angle will also slacken seat angle. And it will slightly shorten the distance to you bars as they will be angled back towards you slightly. At just 1 degree you may not notice the change in reach much though.

What you are suggesting is worth trying but the other (more expensive) option is a longer fork. It will slacken the head angle and give you some extra squish.

I’m not sure what fork you are on now but a burlier fork can feel like a big improvement through rough, rocky and rooty terrain too as it resists twisting and deflecting.
Wouldn't putting a negative angle headset in steepen your seat angle slightly if you kept the same fork travel as it will drop the front(talking mm here)? Longer fork will slacken the seat angle.
 

Kerplunk

Likes Bikes and Dirt
Wouldn't putting a negative angle headset in steepen your seat angle slightly if you kept the same fork travel as it will drop the front(talking mm here)? Longer fork will slacken the seat angle.
I put all the geo into a calculator.. -1 headset and it slightly lengthens reach/wheelbase, reduces ETT, reduces Stack/BB height.
 

Kerplunk

Likes Bikes and Dirt
I’m not sure what fork you are on now but a burlier fork can feel like a big improvement through rough, rocky and rooty terrain too as it resists twisting and deflecting.
Fox 34 130mm, it’s stiff enough for this sort of bike. I had thought about bumping up the travel on it to 140mm but I have finally got it dialed with extra tokens and higher psi. Don’t feel under forked anymore.
 

beeb

Dr. Beebenson, PhD HA, ST, Offset (hons)
If you run spacers under your stem, the reach measurement will increase (as it's measured to the top of the headtube), but your physical reach to the bars will likely marginally decrease as the bars will be tipped back toward you more.

Overall with a -1 degree headset I didn't really feel any cockpit fit changes, but a 10mm longer fork changed the feel of the bike quite a bit overall (taller front, slacker seat tube and more rearward seated weight bias). -1 degree mainly gives you a little more front centre, and makes the front-end slightly better at absorbing impacts through rocks.
 

Kerplunk

Likes Bikes and Dirt
If you run spacers under your stem, the reach measurement will increase (as it's measured to the top of the headtube), but your physical reach to the bars will likely marginally decrease as the bars will be tipped back toward you more.

Overall with a -1 degree headset I didn't really feel any cockpit fit changes, but a 10mm longer fork changed the feel of the bike quite a bit overall (taller front, slacker seat tube and more rearward seated weight bias). -1 degree mainly gives you a little more front centre, and makes the front-end slightly better at absorbing impacts through rocks.
Thanks Beeb, that’s what I am looking for, a bit more front centre to match the longer chainstays. I have spacers under the stem so I can tweak the cockpit fit if needed. Slacking the seat angle further (currently at ~73.5 odd) I think would only make things worse than better.
 

yuley95

soft-arse Yuley is on the lifts again
Wouldn't putting a negative angle headset in steepen your seat angle slightly if you kept the same fork travel as it will drop the front(talking mm here)? Longer fork will slacken the seat angle.
Sorry - you’re right. Was picturing longer fork tilting everything back. Thought I reckon seat angle should stay reasonably static shouldn’t it?
 

ozzybmx

taking a shit with my boobs out
...use offset bushings?
Nice one ! Looked at slackening my Trek XC race bike a few weeks back, both IS cups and E2 geo, no good. The offset bushings will give me 1° with an 8mm bolt. It climbs like monkey but its not so nice on descents at 69.5°.

Did the vernier stuff this afternoon, will order some tonight.
 

leitch

Feelin' a bit rrranty
Hey @Kerplunk what size is your Spider? I have a -1º Works headset that I had on my 5010 that I'm no longer using if you want to try before you buy/save some pennies. It's zs44/ec49 so according to my Google should fit your frame provided you fall within the 108-122mm head tube length range. FWIW it was a great addition to the 5010 for all the reasons you've described above. I'd used offset bushes in the past but the headset was a far superior solution on a bike with slacker seat angle/shorter reach than is now more common.
 

Kerplunk

Likes Bikes and Dirt
Hey @Kerplunk what size is your Spider? I have a -1º Works headset that I had on my 5010 that I'm no longer using if you want to try before you buy/save some pennies. It's zs44/ec49 so according to my Google should fit your frame provided you fall within the 108-122mm head tube length range. FWIW it was a great addition to the 5010 for all the reasons you've described above. I'd used offset bushes in the past but the headset was a far superior solution on a bike with slacker seat angle/shorter reach than is now more common.
Pm sent @leitch
 
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komdotkom

Likes Bikes and Dirt
I've got 150mm DVO Diamonds on my Spider 29c and they made a huge difference to it's descending capabilities coming from 120mm Fox32 Stepcast noodles. No noticeable negatives apart from the additional weight
 

Scotty T

Walks the walk
Hey @Kerplunk what size is your Spider? I have a -1º Works headset that I had on my 5010 that I'm no longer using if you want to try before you buy/save some pennies. It's zs44/ec49 so according to my Google should fit your frame provided you fall within the 108-122mm head tube length range. FWIW it was a great addition to the 5010 for all the reasons you've described above. I'd used offset bushes in the past but the headset was a far superior solution on a bike with slacker seat angle/shorter reach than is now more common.
Cool, I will look at these for the Juliana v1 I got for the missus, it could be a tiny bit less twitchy.
 

Kerplunk

Likes Bikes and Dirt
Just a quick update, burner leitch was able to supply me with a -1 angleset and I managed to press it in straight after a bunch of goes..
Went for the first quick spin today and happy to say it definitely calmed down the front end as advertised. Bike also feels a more stable with the front wheel raked a bit further out infront. Head angle is now 67 degrees which feels right for this sort of bike..
Be good to hit some longer rocky trails to really test it out..
 

safreek

*******
Damn, if you have the loot go angleset, offset bushings and 160mm fork, slacken it by 5 degrees or so. What could go wrong
 
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