Oh I have gone all saggy ....

[2manyoranges]

I freaked out everyone in the 1990s when I insisted on having 30% sag on my ProFlex 853, Amp B3 and Pace forks on my hardtails. 'It's a waste of travel' they said. 'there's no reason why...' they said. When I ordered soft elastomers for the ProFlex, Magic Cycles genuinely said 'you don't need them...you just don't need them....'. The bike worked brilliantly.

At 170 and 66kg I am certainly lightweight. But I do like hammering trails....

And I like my suspension to DROP into things as well as respond to bumps. Sag is a vital feature of suspension systems - it sets the mass hanging in a spring system rather than balanced on top.

i now have some long travel DH and ENDURO full suspension bikes, but love my hardtails. With 150mm and 160mm of front travel. WHAAAAT??? say friends. 'That's completely unnecessary' they say. 'when you burn through the travel you just upset the geometry of the bike....' they say.

I see it differently.

Stanton, for example, quote frame angles with a 140mm fork 25% into the sag.
This makes the available travel 105mm.

I use a 2deg angleset (works components) to slacken the head angle 1-2deg, which uses up around 15mm of travel. So my 160 fork is now a 145...which makes the available travel at 25% sag 120mm. I can now increase sag, and if I increase it to 30% (COTIC use 30% and PIPEDREAM 40%) then 145-43.5 = 102.5mm.

Which means a 160 fork gives me a tiny bit LESS travel than a 140 on 25% sag. Which is what the frame is designed for.

I now do not have a madly elevated bike, I have a lot more control all the time since I have increased trail and more suspension to drop into depressions when I ride, and I LIKE IT.

Being saggy that is.

One reason I know that this setup is good is that I get VERY good small bump sensitivity, good support, and at the end of a ride my marker ring is about 80% through the travel.

Of course, the magic setup for any fork is initial fast breakaway to deal with small bumps, then support in the midstroke, then rapid ramp up on really big hits. Getting that is a lot easier with longer forks, I think, since I can play with compression damping and rebound and have a more sensitive set of changes for any given adjustment. I am just wrangling a Cane Creek Helm COIL SPRING fork which is really promising on the bench - very low breakaway then good support in the mid stroke despite the linear nature of the spring. This is in the workshop. It will be interesting to see it in anger on the trail. I have yet to get a frame but I think a Pipedream Moxie, Kingdom Vendetta2, Cotic BfE last gen or Stanton Slackline gen3. Should be fun.

 

[lou74]

Back in the 90's the likes of Performance Bikes and Fast Bikes would bang on about 'static sag' in articles about suspension set-up. Because it's important, the beginning of setting up everything else. Tent amount to witchcraft is suspension set-up, up there with carburetion..... Black magic... (I did learn stuff when I worked in a motorbike shop)
Clearly you understood the mechanics of suspension where as the others didn't, although setting static sag with elastomers was a bit tricky

 

[2manyoranges]

Back in the 90's the likes of Performance Bikes and Fast Bikes would bang on about 'static sag' in articles about suspension set-up. Because it's important, the beginning of setting up everything else. Tent amount to witchcraft is suspension set-up, up there with carburetion..... Black magic... (I did learn stuff when I worked in a motorbike shop)
Clearly you understood the mechanics of suspension where as the others didn't, although setting static sag with elastomers was a bit tricky

Interestingly, the Big Yellow Elastomer versions of the Proflex w Girvin forks allowed for combinations of Hard Med and Soft elastomers, and you could cut them in half too, which meant for some very interesting combinations of suspension curve. Ultimately, at my low weight (120 lbs) I simply ran the bikes with all Soft - and that seemed to work well….

I love the Black Magic of carburation - Ian Tyrell runs up a V12 and then listens to the walls of the intakes using a tube. And then makes tiny tiny adjustments until things are ‘just right’. And he does know….the plugs tell a story 500 miles later - neither lean nor rich….

 

[clubby]

I use a 2deg angleset (works components) to slacken the head angle 1-2deg, which uses up around 15mm of travel. So my 160 fork is now a 145...which makes the available travel at 25% sag 120mm. I can now increase sag, and if I increase it to 30% (COTIC use 30% and PIPEDREAM 40%) then 145-43.5 = 102.5mm.

Which means a 160 fork gives me a tiny bit LESS travel than a 140 on 25% sag. Which is what the frame is designed for.

No it doesn’t. Angle set won’t change travel. It will change bar height but that’s not the same as travel.

 

[2manyoranges]

No it doesn’t. Angle set won’t change travel. It will change bar height but that’s not the same as travel.

Sorry I put it in strange words.
If you change the angle, a given length will be lifted slightly higher at the base end, thus effectively reducing VERTICAL travel but not the ACTUAL travel of the forks.

Comme sa