Home › Forums › Bike Forum › Who runs slack HA on their HT bikes?
- This topic has 78 replies, 37 voices, and was last updated 13 years ago by Jeffus.
-
Who runs slack HA on their HT bikes?
-
SpokesCyclesFree Member
No, I run a 68.3 degree head angle with 140mm forks on an old Sovereign.
I’m unconvinced by super slack HAs on hardtails- on a bouncer, it’s great, but you do have a rear shock to soak it up. You don’t on a hardtail, you “work the fork” (tm and c bikeradar 2008) and this needs a steeper head angle in my opinion. I don’t think a steep head angle is for everyone, but I think a skilled rider will get more out of a slightly steeper HA.
littlegirlbunnyFree MemberI got a small chammy frame with Lyriks on. Gawd knows what the head angle is, prolly about 66-67? It’s fab for steep stuff, DH stuff, bit wishywashy for pedally undulating techy trails, and a pig to climb with unless I wind the forks down. Never liked climbing much on a HT anyway, so the forks tend to stay at 160.
_tom_Free Member68degs static is 70degs with 30% sag.
Trailstar must have been about 74 then, that’s approaching a bmx HA 😕 I don’t run 30% sag though, probably around 20 if that. Feels a bit “wallowy” to me if there’s more than that.
brantFree MemberWorking the fork is a whole lot easier when it’s not trying to throw you off the front.
ooOOooFree MemberI thought trail was set on the fork. Is 90mm a horiz measurement brant?
NorthwindFull MemberSpokesCycles – Member
“I’m unconvinced by super slack HAs on hardtails- on a bouncer, it’s great, but you do have a rear shock to soak it up. You don’t on a hardtail, you “work the fork” (tm and c bikeradar 2008) and this needs a steeper head angle in my opinion.”
I don’t get this at all. It’s a lot easier to work the fork on a slacker bike, whether it’s a full suss or a hardtail. Or so I’ve found anyway. Could you explain what you mean any more?
brantFree MemberRake is set. Trail is a function of wheelsize, head angle and rake.
SpokesCyclesFree MemberI just find it easier being a bit more over the front, on everything. Obviously, what I run isn’t steep by any means. The superslack stuff like the 64.5 Ragleys just don’t particularly light my fire.
When you corner on an ht you’re over the front more, on a bouncer you’re over the back more. A steeper ha helps with that.
SpokesCyclesFree MemberNot enough on the super slack ones, no- hence not convinced rather than don’t like. I have jacked mine back to 67 degrees with a bigger fork for a while and it didn’t make any sense to me.
I can see the place for them, though. The 64 degree thing in t’alps would be exciting.
AndyhiltonFree MemberMy Stiffee falls into the slack category at 66 with pikes set to 140. Feels fine for everything to me, although I do wind my forks down for climbs.
chiefgrooveguruFull MemberDo longer travel forks have less rake to reduce the decrease in trail as the head angle steepens as the fork compresses?
steve_b77Free MemberI thought my Cove Handjob was pretty slack with a shortish fork on it, measured it at 67.5 with 115mm Rebas on there.
Handles like a dream on quick stuff but not as quick on tight stuff as my Genesis iO with a 70.5 HA (all static)
I’m tempted to try the 130mm Revs I’ve got on it, should see about 67 static, if I get hold of a pair of 2010 ones for my FS
stevehFull MemberBrant – How does a 456 SS compare to an mmmbop? I’ve got my summer season with 160mm 36 van r’s and love the slackness but would be interested in trying an mmmbop if it’s likely to be even slacker.
Mr whiles you may now call me a deviant again. I blame riding dh bikes…
NorthwindFull MemberSpokesCycles – Member
“Not enough on the super slack ones, no- hence not convinced rather than don’t like. I have jacked mine back to 67 degrees with a bigger fork for a while and it didn’t make any sense to me. “
Yup, sure, but there’s a big difference between just pouring extra fork into the front of a bike to slacken the HA, and designing a bike from the ground up for it.
JeffusFree MemberI love my mmmBop’s slack feel I’m running a FOX Talas 32 150mm, 15mm axle,taper steerer , just feels good.
Brant a quick question is the Nuke Proof Mega similar angles to the mmmBop?? I am thinking of buying one when they come out 😀
GWFree MemberIt’s a lot easier to work the fork on a slacker bike, whether it’s a full suss or a hardtail.
WTF BS is “working the fork”? please explain what you mean?
FWIW my main bike is a 100mm forked hardtail with a 69deg HA and I use it for XC, DJ and DH.. I rode another 100mm hardtail with a 63deg HA for a few years for XC only alongside my main hardtail, super slack HA don’t DJ too well so I stuck lighter parts on it. there’s far more to a hardtails handling than just the HA.
brantFree MemberBrant a quick question is the Nuke Proof Mega similar angles to the mmmBop?? I am thinking of buying one when they come out
The Mega is a 66deg head angle, so depending on how you set the rear up, is similar/slacker than the Ragley. But it is designed for going quite a lot faster 🙂
there’s far more to a hardtails handling than just the HA.
Sure is – the “I can get a slack head angle by putting a long fork on” thing is a bit daft.
brantFree MemberBrant – How does a 456 SS compare to an mmmbop? I’ve got my summer season with 160mm 36 van r’s and love the slackness but would be interested in trying an mmmbop if it’s likely to be even slacker
I think, thought i haven’t looked for a bit, that it’s pretty similar h/a. However, mmmbop will end up with a slightly lower BB, steeper seat angle, though a similar kind of reach to the bars (shorter top tube, but steeper seat angle puts the bars in the same place, ish).
bravohotel9erFree MemberCommencal Ramones 2 on Pikes…67 I believe.
Slack and fun.
poppaFree MemberWTF BS is “working the fork”? please explain what you mean?
As far as I can tell, working the fork means biasing your weight forwards so that when you hit something the fork takes the brunt of the impact, whilst the back end ‘skips’ more.
Best tried with caution though. If you overdo it you end up being a lot more likely to go over the bars. Which is where the slack head angle thing comes in.
I think you need a bit of skill to do it properly IMO, probably best off weighting the fork for smaller roughness and unweighting/hopping over the big stuff where possible.
BadlyWiredDogFull MemberI built up a Blue Pig a few months back because after riding a Ragley Ti briefly, I thought it was intriguing. Back to back with a Hummer, the Cove felt sweet and balanced, but the Ragley – even with a not brilliant fork, I thought – was just, er, interesting.
The thing that works brilliantly with the Pig is the steeper seat tube. I’ve ridden several bikes with forks longer than intended – I’ve just taken a 150mm Rev off my RC405 because it felt wrong – but that’s quite a different thing as while you might get a slack head angle, you also cant the seat backwards and screw up the weight distribution and BB height, most notable on climbs, but also generally. It’s night and day compared to something that’s designed from the ground up to work with a slack head angle and long-ish fork.
Anyway, yes, love the downhill stability, the climbability and the composure on steep, techy descents. I’m a very normal sort of rider, but the Pig makes me feel that I might actually, occasionally, be semi competent… works well in the snow too, harder to knock off line.
It does take a few rides to get used to and the Pig’s a bit grumpy on meandery, flatter stuff, but ride one somewhere hilly and techy for a while and it all makes sense.
thisisnotaspoonFree MemberIt thought it was designed precisely so that you CAN climb on it with a big fork. If you are desperate to use your TALAS you can always get a different frame though
2007 Z1 RC2 forks, 150mm at full travel, set to give 1/3 sag and plenty of compression damping to keep them from being wallowy. Flick the ETA switch to climb though and its just becomes impossible, the only thing I can think of is that the seat angle must be becoming soo steep that it comes to a point where I’m trying to use the wrong muslces to turn the pedals, there jsut isn’t any power!
Next summer I’ll be on a 16″ mmmbop or summer season with a layback poost to compensate.
Either that or a full susser 🙂
messiahFree MemberA few thoughts.
My Balfa has a 66deg head angle and 70deg seat angle with 120mm forks. I’d like the seat angle a little steeper as techy steep climbing is a nose of the saddle tricky affair.
My Whyte 19 has 67deg head angle and 71deg seat angle with 120mm forks. Climbs and rides okay but the high bottom bracket makes it unstable and a bit of a handfull in the nadgery fun stuff… but it does the miles better than the Balfa
I demo’d a Cotic Soda – 68 head angle and 70deg seat angle with 120mm forks. Bottom bracket was lower than the Whyte and the same as the Balfa, which made it feel great much of the time, but it didn’t have the stability of the Balfa and Whyte when really pushed into the gnar… the bike had a tendency to “stall” when hitting things and felt like it didn’t want to roll over them as effectively as the other two bikes. It also didn’t recover as well from jumps and drops as if when being at full compresion I felt pitched over the front. Obviously this could be set up and other issues but I think the head angle had a lot to do with it. I like the feel of the head angle on the Whyte and Balfa as they suit my rather “blunt” and “bludgeoning” style of riding.
On all the above bikes I ended up running the saddle forward on the rails to make the bikes climb better – probably making the seat angle more like 72/73 deg. None of the above are perfect for what I want… if I had the cash I would get something made or at least keep trying some other frames. It’s hard enough to keep up with the bits I break and wear out without buying lots of things to try 🙄
Brant… I’ve tried an 18 Ragley but it was too big and simply felt wrong for me. I would love to try a 16 or the 17 when they come out… perhaps when I decide I’ve had enough of the Whyte (or I break it again).
My full suss bike has a 65 head angle and 72 seat angle (saddle forward again) – it really suits my style of riding just fine.
Side note – I don’t understand how people can use “sag” to modify the geometry for a longer fork. I tried it… and when I used a lot of sag I’d be bottoming the fork out all the time and eventually breaking it… but it also gave little benefit on the steep climbs as the fork is unweighted and hence at max extension anyway… so no point. Travel adjust forks also don’t work for me as I always end up forgetting to change the travel 😈
brantFree Member71.5deg static seat angle on a 16in Ragley (with 140 forks). Half a degree steeper on an 18in, or half that on a 17in. Degree steeper on a 20in.
ooOOooFree Memberthe only thing I can think of is that the seat angle must be becoming soo steep that it comes to a point where I’m trying to use the wrong muslces to turn the pedals, there jsut isn’t any power!
Yeah I understand this. Do you prefer to spin or pedal slowly on climbs?
Rake is set. Trail is a function of wheelsize, head angle and rake.
Thanks for that, think I’ve seen a few sites where they describe fork offset as trail.
brantFree MemberI’ve seen a few sites where they describe fork offset as trail.
They are wrong then.
Fork offset can be called “offset” or “rake”. But not trail. Trail is something else.
Oh – and regarding the ETA = no power… I’m sure several people reported a phenomena where lockdown forks make it feel like you’re riding with the brakes on.
Ragleys are designed to climb without lock down. As I always forgot to take it off.
kelvinFull MemberThis might help some people here talking about the BFe:
http://www.cotic.co.uk/geek/#forks
“All angles are based on appropriately sagged forks”
kelvinFull MemberBFe with 140mm Pikes so I guess about 68 degrees? Feels well nice after being used to a 71 degree head angle for so long.
68degs static is 70degs with 30% sag.
BFe probably is about 68 degrees with 140mm Pikes WITH 30% sag.
thisisnotaspoonFree MemberYeah I understand this. Do you prefer to spin or pedal slowly on climbs?
Somewhere between the two, flat pedals but tend to sty and stick in the lowest gear possible and shift up when i run out of spin rather than a high gear and shift down when it becomes too hard.
ooOOooFree MemberHey that is a great page on the cotic site Kelvin
Hmmmm mr spoon I guess I’m similar to you, but I was thinking that steep seat angles make it harder to get the power down, when you pedal slowly. I seem to need a layback post on all my bikes
james-oFree MemberWe probably talk about HA in detail as it’s easier to measure than trail and sus forks all have a similar rake, or it can’t changed at least. Trail’s the important bit tho.
Stem and weight dist variables can counter excess flip-flop but generally i like a HT that’s slackened off to just at or before the point of having a noticable ‘flip-flop’ steering feel at ride height. Seems like a nice balance all-round and is as confident handling as a hardtail needs to be w/o feeling ‘slow steering’ etc. 80-90mm trail at ride height seems to be about there.
ooOOooFree MemberIs there a similar measurement for where your hands are, relative to the contact patch? That must change a lot between a xc frame w/ long stem & dh frame w/ stubby stem, more than the trail varies I’d imagine.
brantFree MemberCertainly when falling down things, with lots of weight on your front wheel/rear wheel in the air, the relationship between contact patch and handlebar position is certainly important 🙂
BlowerFree MemberSpokescycles – the blue pig works well and balanced due to the seat angle,over the front
be honest ive never had a hardtail frame which has worked so well as this one ever!JeffusFree Member[The Mega is a 66deg head angle, so depending on how you set the rear up, is similar/slacker than the Ragley. But it is designed for going quite a lot faster ] Thanks Brant, I like the feel/size etc of my mmmBop and to have a full sus similar would be great.
I’ve had a few hardtail with long travel SC Chameleon 140mm Pike, Orange P7 140mm Revelation and now the mmmBop 150mm Fox, all have been fun the Orange was really good and the Ragley is proving to be another good un.Just need to save up for a dropper seat post.
The topic ‘Who runs slack HA on their HT bikes?’ is closed to new replies.