I used to like the steeper trails out there (think Afan UKGE Stage 4 & others of that ilk in the area, various off piste in the FoD, etc). But I rode them by running 12psi and a 40mm stem. I've since realised this isn't the best for most other riding, and now with 20psi + 70mm stem I'm struggling to maintain control on anything that goes properly downhill, unless it's a straight line.
Any advice?
40 to 70 is a big jump. something in the middle?
18psi and a 55mm stem?
There is a direct relationship between the stem length and bar width - sounds controversial, but try narrower bars? It will allow you to get your weight further back, as you could with the shorter stem.
Sounds like you need to go full lycra, forget the steep stuff
That's some pretty extreme changes! What's the bike? What bars?
19psi, 36.7mm stem?
DrP
Only 1 solution really: New bike.
why have you changed for longer stem?
"not the best for most other riding"
It's always going to be a compromise.
I'd be concentrating on optimising it for the bits you enjoy the most.
[s]7[/s]12psi? Crikey, in what wheels/tyres?
Enduro 29.
Tyres, minion 2.3 29er, what's the lowest you can go without them squirming on fast corners I wonder?
The extreme stem change is from the short stem I had to experiment with back to the stock one. Why longer stem? because after a coaching session on jumps I'm told the bike is too short for me. New bike is obviously the answer 😉
I may well settle on something in between, but let's face it the weakest link is me not the bike, I was hoping for more of a discussion on technique - which means the full lycra comment is the most apt so far!
@dangrourbrian I think you're getting confused with scuba there
If only they did dropper stems so you could adjust the length on the fly...
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Wouldn't fancy adjusting it on the fly, though
minion 2.3 29er
I find my 2.5 bloody awful below about 25 on the front and my 2.3 highroller flops and rolls about much below 25 or so I the rear (peels off my rims in hard corners below 20ish)
I tend to run about 30 both ends. Ymmv of course.
Yes spotted that sideshow!
Yeah I'm still trying to find that sweet spot for pressure. That sounds particularly bad though, mine corner fine at 20psi, are you on narrow rims? 30mm here.
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When Ann Summers and CRC packages collide...
DrP
after a coaching session on jumps I'm told the bike is too short for me
O really?
If your bars have some rise, put the 40mm stem back on and roll them forwards which will give you more effective stem length.
I don't see how 12psi in a Minion 2.3 is rideable unless you're incredibly light - or more likely that the gauge on your pump is way out - which means 20+psi on your pump might actually be 30+!
On a tyre like that I'd say twice your weight in stone in psi is about right to hold up in berms, maybe a bit lower, unless you're pumping super hard. I can get away with about 22psi with 2.4 and 2.5 Maxxis.
Yeah I'm still trying to find that sweet spot for pressure. That sounds particularly bad though, mine corner fine at 20psi, are you on narrow rims? 30mm here.
30mm lb carbon with those.
Shorty 2.5/2.3 on roval 29mm at similar pressures
Mkii 2.4/2.2 on i25s at 30 and a bit
Mud x 2.0 and storm control 2.0 on mavic 319 at 40ish
As above, i imagine your gauge is wrong...
May I just suggest in future that if you're after advice on form/technique you voice your question as such, it just appears to be a question regarding component selection. Changing the length of your stem especially will require an adjustment to how you handle the bike. As the stem has gotten longer you'll be positioned further forward on the bike. This is good for climbing however putting more weight on the rear is better for descending, I'd recommend leaning a little further back which might feel odd at first but should help improve your positioning somewhat.
May I just suggest in future that if you're after advice on form/technique you voice your question as such, it just appears to be a question regarding component selection. Changing the length of your stem especially will require an adjustment to how you handle the bike. As the stem has gotten longer you'll be positioned further forward on the bike. This is good for climbing however putting more weight on the rear is better for descending, I'd recommend leaning a little further back which might feel odd at first but should help improve your positioning somewhat.
I don't see how 12psi in a Minion 2.3 is rideable unless you're incredibly light - or more likely that the gauge on your pump is way out - which means 20+psi on your pump might actually be 30+!
I've given up on pumps with pressure gauges, I check by feel when letting out air at the top of the hill, plus have a digital gauge I use on occasion (which has confirmed the pump gauge fwiw). I was as surprised as you to find I used to run 12. Sometimes it was even 9! Put it this way when I press the tread with my thumbs I can depress it a couple of cm.
I weigh 95kg without kit. I'm running tubes, so they don't burp, and only recently came to realise how I dislike squirm on corners.
I used to pinch flat a lot on the hardtail but with minions, 160mm travel and 29 inch wheels it doesn't happen much any more, at least not on the really steep stuff as I'm never going all that fast. (I like to think I got better at riding somewhere along the line as well...)
Good point about thread title Kraken.
70mm! its not 1997
just put the 40 back on and lean forward on the climbs!
Those are silly low pressures - I'm amazed you weren't burping them all over the place. I've ended up running at around 30psi.
I check by feel when letting out air at the top of the hill
Problem 1: You have no real idea what pressure you're running.
I weigh 95kg without kit.
Problem 2: 12 PSI is much too low for someone your weight.
8.3 inch contact patch between two 2.3" (2.3/2^2*pi*2) tyres and you weigh 210lbs that makes the pressure on the ground 25 pounds per square inch. at less than half that in the tyres you're essentially running on your rims and the rubber is only providing grip!
12psi? GRIM! set it closer to 30psi and pop a 50mm stem on. I don't know one person who runs pressures that low because it is horribly squirmy even on loam.
I am amused by your witch hunting seeing as I said at the top I now run 20psi
Low pressures are anything but grim though if you like grip and a total absence of trail chatter. That's what the whole fatbike/plus thing was about. Just don't try to rail a berm at speed if you want to ride out of it!
Low pressures are anything but grim though if you like grip and a total absence of trail chatter. That's what the whole fatbike/plus thing was about
But much higher volume tyres. Katie's maybe 60kg with kit and while she can get away with running sub 20psi it destroyed the sidewalls very quickly.
I can put up with trashed sidewalls. Squirm on corners not so much.
12psi? You must ride very, very slowly. In which case, i don't think the exact length of your stem is going to make any difference...... 😀
I now want to make a meme with that non-robin-williams dude from Good Morning Vietnam saying 'deep inside, I know I am fast'. 😀
Though I'm willing to bet a good chunk of STW couldn't ride Afan Stage 4 at all before they repaired the monster ruts on it.
Given you're on a 29 enduro i believe it's going to be fairly recent geo as i don't think they've been available too long before the long low slack revolution.(i stand ready to be corrected mind)
On that basis dump the 70mm stem and go back to shorter one. If you're comfy with squishy tyres and able to ride without pinching and ruining your wheels every time you so much as imagine a rock (i wouldn't be but I'm not you), go back to lower pressures.
What things are you trying to ride that made you think a longer stem would be better? What are you riding where low pressure was a problem that made you want to increase it?
I'm willing to bet a good chunk of STW couldn't ride Afan Stage 4 at all before they repaired the monster ruts on it.
So why ask us?
40 to 70 is massive- only 30mm is almost double. But maybe 40mm isn't right either. I settled on 50mm for the remedy after dabbling with 35 and 40, it's just the right balance for me.
That you SurfMatt?
So why ask us?
Cos I'm just about awake enough not to fall for the [url= https://en.wikipedia.org/wiki/Ecological_fallacy ]ecological fallacy[/url]?
Jeez! put the stem back on! Then push the saddle back as far as it'll go - the stem will have a massive impact on handling on steeps - I ride a bike (round FoD a lot) which is slightly too short but wouldn't consider a stem longer than 50mm now. Some of the stuff round FoD is just too steep so I'd never want to push my weight further forward over the axle and into impending doom
Though I'm willing to bet a good chunk of STW couldn't ride Afan Stage 4 at all before they repaired the monster ruts on it.
It's really not that steep, or hard.
As for 12psi, Must feel awful - are you dinging the rim on every single bump? That would literally last the first corner, even at moderate pace before the rim & tyre parted company.
The thing to bear in mind with stem length, is a 30mm stem is basically a zero stem - lay a metre rule on top of the steerer (perpendicular to the steering axis) and it'll pass straight through the grips with a normal shape bar. So with your 40 and 70mm stems, you're actually comparing the difference in steering feel between a 10mm effective length stem and a 40mm effective length stem - which is huge!
The other thing to consider is that the Enduro 29 is not exactly long of front centre or low of BB for such a hard-hitting bike - so a 70mm stem is likely to move you ominously close to the front contact patch compared to on a longer bike.
I'd go back to the 40mm stem, fiddle with your bars and stick a 2.5 Minion up front which will allow to to get similar grip to the 2.3 whilst having the pressure high enough to ride berms. Keep the old 2.3 for the back.
If Specialized didn't use a weird head tube standard your other option would be to add an angleset - my super-slack full-sus runs a 50mm stem and my hardtail a 35mm stem but the front wheel is still quite a long way further in front of the hands on the full-sus.
12psi for anything is just daft. 12psi for jumping is doubly daft. In conclusion you are daft to the power of 2 😛
Shouldn't take more than a couple of corners to get used to a longer stem imo. Sort your tyre pressures out (i'm similar weight on 2.3 29ers and the minimum i'd run would be mid 20s) and ride your bike a bit more - maybe on less steep stuff til you adjust your body position.
I ride an Enduro 29 and agree with what chiefgrooveguru has just said.
For info., I'm 6' tall on a large and run a 45mm stem and 790mm bars. I like a bit of steep stuff and find this combination seems to suit me and the bike. If i was riding on tighter twisty trails in forests, I'd probably stick a 55mm stem and 750-760mm bars on - just to get a bit more tree clearance, but keeping weight on the front wheel to give similar handling. Maybe (depending on your height and size of bike) it'd be worth you trying a 50mm stem and 780mm bars?
As mentioned above, the E29's are a bit conservative in their geometry for a long travel bike, and I notice mine feels slightly more cramped after riding my new shorter travel Cotic (with 35 stem 780 bars).
Tyre pressure wise, if you're running tubes, I reckon you'd be looking more at pressures closer to 30psi to stop squirm - maybe start there and drop the pressure by 1 or 2 psi till you find the best grip-sidewall support compromise. If it's of any help, I'm running tubeless and like to get the pressure as low as possible without tyres bottoming out - however, if I'm going to be riding more aggressively on purpose built bike trails, I tend to stick a bit more air in to stabilise the sidewalls.
The wider bar is a good point - if your bike is a bit short on reach (and you don't have narrow shoulders or limited shoulder mobility) then try some big bars. I'm on SixC 800s, which measure 810mm tip to tip with Deathgrips. Fantastic on the steep or rough stuff.
12psi is grim as is 20psi for your weight unless its a particularly horrific mud track with minimal nasty rocks.
Don't get an angleset as it'll make your bike slacker and pull the bars back to you. If you want to get more cockpit fit an offset headset and you'll gain 6mm reach and a marginally longer wheelbase.
I'd run a 50mm stem and keep bar width the same for now whilst pushing the saddle back as far as it'll go if the bikes too small.
I ride a Zerode with a custom milled 60mm stem as they are tiny bikes and it's absolutely fine down Champery DH so I'd argue it's rider skill and a normal psi that needs to be addressed.
No point getting used to super low psi's as when you change it up to something more normal you probably won't like the feel of your tyres.
I'd say setting your tyres to 30psi and then adjusting by feel is the way to go.
What size Enduro 29 are you running? And how tall are you?
Would be interesting to see if your coach was talking BS, and has just made you change for no reason.
As rickon said.
You sounded happy with the bike before making some changes to aid with jumps?
I guess the obvious question to also ask is have the changes had the desired effects with the jumps? As in helped with them?
EDIT: Best to change one thing at a time I would think too. Tyre pressure, see how it rides. Tyre pressure back to normal then try stem by itself before mixing the 2 up?
Have to say that the large change in stem length gets my vote as a possible issue for you perhaps.