Enduro/gravity bike suspension and geo

[Headshot]

So I had another bike suspension and geo tyre test ride this morning ( See Jimmy). Had a peculiar front slide moment on a slightly off camber hard pack with sand over descent. Weird. No issues on any of the rocky fast stuff and the front tyre feels great at slightly lower pressures. Can't say the same for the rear Butcher which burped or flatted at the bead and lost air again after a reinflation. Time to bin it. 

 

And the geriatric hiking crew were out in force - all over the trails. It was like dodge body. 

[jimmy hardtail]

Dude, really interested in how it rides. Those are some serious figures. And you're what, 3 or.4 years into the development cycle, if you include the hardtail?

[jimmy hardtail]

I've been tinkering with geometry and sizing for a while. My goal is a 29er with a 170 to 180 fork and 160 or more rear. Basically as close to DH as I can go but still able to climb without being impossibly awkward. But actually there is no one bike that can do it all. Enduro style riding, slog up climbs and race down is one thing, but if you want to ride more varied trails it's not so good. So really you can have a race bike or a fun bike. It's very hard to get one to do both

[Headshot]

I have almost managed to stop noticing my new front tyre whcih is a good sign. It just works. My recent suspension adjustments have been the following. Setting the rear sag at around 35% . Increasing the rebound speed to 5 from full open up front and 2 clicks faster out back. I now have the kind of smooth bottomless feel I wanted over repeat hard hits and the bike seems to skip over rather than get caught up on rocks and roots. I felt that  the fork dives a bit too much under braking. That could just be the damper or a lack of compression damping up front. Will play around with that next. 

[Hairy]

good to hear the bike is coming together for you!

 

I have not been on the trails for a few weeks, and managed to get in a ride yesterday. At first I was all over the place, did some tyre kicking and soul searching ... this did nothing to improve the ride. The noticed that my forks compression was completely open (I think the youngest was "dialing in" my suspension for me) .... 3 x clicks of LSC compression on the DVO and she was sitting up tall again and not diving ... knocked it back to 2 x clicks and the bike was glued to the trail again and it had a good feeling in the turns.

 

Amazing how small things make such a big difference.

I have almost managed to stop noticing my new front tyre whcih is a good sign. It just works. My recent suspension adjustments have been the following. Setting the rear sag at around 35% . Increasing the rebound speed to 5 from full open up front and 2 clicks faster out back. I now have the kind of smooth bottomless feel I wanted over repeat hard hits and the bike seems to skip over rather than get caught up on rocks and roots. I felt that  the fork dives a bit too much under braking. That could just be the damper or a lack of compression damping up front. Will play around with that next. 

[Eddy Gordo]

Gotta love how easy it is to setup a dvo!

[Bos]

So I squeezed in a ride in Jonkershoek on Saturday morning and thought I'd share my experience. 

Its always nice to measure yourself against some trails of relevance. You might be KOM'ing your local trails but when you get faced with proper trails it challenges you on new levels. Wish I lived closer or had some proper space to build(and a truckload of freetime

 

It would also be the first time I ride there with my new bike and bigger wheels so was really keen to see how I'd go. The last time I rode the plumber on my RM Element with saddle dropped wasn't a very nice experience(the trail wasn't in the best condition to ad) One can be pretty competitive on the bottom flatter trails. One thing I noted was that Maxim Marott is KOM on a lot of the middle to lower trails and he probably rode his 4'' Cannondale FS. Mans got skills.

 

So once at the top of Saaltjie I had a choice of either Armageddon or Status Quo. I was a bit pushed for time so opted for the Armageddon 8 (bad decision). Main reason was that I've seen some of the features on Status Quo, which some are blind and since being alone and pressed for time, I wasn't keen on stopping to push back up all the time. Armageddon 8 is boring as SH*s though. 

 

But then there's Iron monkey, which I really wanted to ride (never rode it before) and the top bit of that was really awesome. Wow. Flows so well. IM 5 is however a proper test of strength and skill. Also really enjoyed it. The two doubles halfway down just before the drop(If I remember correctly) I rode around and I'm not sure I would have made since there was also a bit of headwind, but that trail is awesome. A real trail rewarding aggressive riding and a real test of the bikes most of us seem to be riding these days. 

 

Some pointers to take away for me:

1. I almost lost my grip on the bar for a second. These foam grips are not grippy enough for the rough stuff)

2. I can do with a wider front tire.. need a 2.4/2.5 for those rocks

3. I'm not so sure my fork is set up right. However It could be that I started getting tired, or that im just not use to it. Its set up quite progressively and I have a bit of LSC to keep it riding higher. My Formula 35 fork has these interchangable compression valves that serve as custom tunes. It felt to me that the combination of the slightly harsh LSC which I felt on rounderslow to medium speed hits especially Iron Monkey 5 and the sharp increase in progression from 3 volume spacers gave me a real workout. Id be keen to ride a Pike down there and see how it feels. However I think I need to swap out the Compression circuit for one with a flatter end of stroke(falling rate) and a firmer initial and mid stroke. Ride slightly higher pressure and take some volume spacers out. 

 

Felt perfect on everything else up to now..

[Headshot]

Nice. We were out Jonks way on Sunday for a party and boy was it raining. Trails must be mint after that.

 

Bos, what bike are you on? 

 

Foam grips are a no no for techncial riding. I tried them once and hated it. Some nice sticky ODI's are far and away the best. Currently I have Nukeproof Horizons on my Enduro which are also very good. 

 

Not sure that wider tyres work better on rocks. What are you running right now?

[Odinson]

Nice, simple article over on enduromtb on suspension kinematics: https://enduro-mtb.com/en/mtb-suspension-kinematics/

[Duane_Bosch]

List of words that #Enduro riders use but don't actually know what they mean.

 

1. Kinematics

 

It's a pretty short list I'll admit.

Sorry not aimed at you Odinson. I just can't with the overuse that word.

Edited February 4, 2019 by Duane_Bosch

[Bos]

Nice. We were out Jonks way on Sunday for a party and boy was it raining. Trails must be mint after that.

 

Bos, what bike are you on? 

 

Foam grips are a no no for techncial riding. I tried them once and hated it. Some nice sticky ODI's are far and away the best. Currently I have Nukeproof Horizons on my Enduro which are also very good. 

 

Not sure that wider tyres work better on rocks. What are you running right now?

 

I'm on a Chinese carbon 135mm Horst-link varient. Looks a bit like a Trek EX. Reasonably updated geo. Really wanted a one bike quiver since I use to be into marathons for a couple of years.. Got that last year and then upgraded wheels and fork for Christmass. I found as it became more capable, I rode less distance and more fun stuff and I just wrote off tires and rims, so I decided, the hell with it, I'm letting go and going back over to the dark side Its been a fun journey.

 

Speaking of Kinematics..

I quite like the Horst link. I have had VPP and Singlepivot's before. The HLink is incredibly sensitive and active with minimal feedback, so much so that I really use the middle position on my Fox DPS rear shock a lot. Pretty much only open her up for downhills. Makes the bike feel like I went from a 110mm to 135mm instantly. I'm pretty happy with the rear I must say. I hope to see some options similar to what Scott is doing available aftermarket. Reducing the volume is really the best way to make a bike feel like a shorter travel version since it doesn't mess with small-bump sensitivity etc. 

 

Regarding the Grips, Heck yes. I'm getting some real rubber. Will look at those options.

My Front tyre is a 2.25 IBEX on a 30mm ID rim. The tyre is pretty good, I quite like it. I will replace with wider once worn out though. 

Got a couple of upgrades to sort out and a family to feed so its a work in progress. I feel like its a capable enough for what I need and can build on it..  

[Bos]

@ Headshot. Its made by a ICAN and they called it the P8.. 

[Headshot]

After fighting off most of a severe snot sinus bug I managed to get out on the Kirstenbosch XC loop yesterday afternoon. My bike is set up in the high position, around 35% sag and 26 psi in the Aggressor front tyre. With this set up it pedals well enough to almost never need the pedal lever on the shock. 

 

I took it down the same track I experienced the big front wheel slide with the Butcher. I didnt notice any lack of grip there but interestingly started to sense that the tyre gives a bit but never lets go enough to need a serious correction. Its predictable once you get used to it. One of the reviews I read mentioned this trait. While the time proves nothing really, I did get a PB down the slithery Newlands forest heep track descent which may point to greater confidence in my front tyre, or a relative lack of traffic, or both.

[Steven Knoetze (sk27)]

I will not lie and say I have read through this entire thread but I do have a geometry question.

My bike is setup up with the same travel suspension as per said manufacturers geometry chart yet I get different angles for my head angle and seat tube angle.

Why would this be?

Yes the tyres and rims may differ, could it be this?

More my own internal curiosity than anything.

I am also using an android app called AngleMeterPro2 so there is the inaccuracies of said app to consider too.

Anyway, any feedback appreciated.

[Steven Knoetze (sk27)]

Double post  

Edited February 13, 2019 by Steven Knoetze (sk27)

[Headshot]

And following on from the Chromag HT monster truck in teh other thread, there wa a heated debate on PB re how a long travel fork will or wont work on a hardtail. Some rather misguided opinions being expressed. Along teh lines of, on steep stuff, the front will go too low and you'll go over the bars. 

 

My point was that a dual suspension biks rear suspension extends on descents to some extent anyway and that my experience does not bear this out at all. What do you long travel HT riders say?