Can't get enough weight on front wheel

[anfos]

I have Giant Stance E+2 2021 size Large which is on the bigger size spectrum for me (I am between sizes). I seem to not be able to put enough weight on the front wheel to aid with grip for turns. For 90kg rider + gear I am using 80 psi on the Suntour fork which barely compresses on the flats. I have also changed the stem to a 70mm -17 to get in a lower position since I also used to do a lot of road cycling but I feel like going to a -35 deg stem.

Before changing the stem again should I use less air on the forks or tires and do some testing?
Since I do a lot of tarmac before getting to the trails I like to use ~30 psi on the front tire, let me know what kind of pressures I should try for both tire and fork to see if that improves things? Thanks!

 

[Mat_Ron]

Regarding forks, you need adjust the air pressure to set your sag to around 30% of the travel. Then check that you are using at least 90% of the travel on the hardest hits. If you are not using most of the travel of the fork, with correct sag, then you may need to remove a volume spacer and try again. If you are blowing through all of the travel with correct sag then you will need to add a volume spacer. Tire air pressure sounds about right. Riding style/experience can also play a part in the problems you describe.

 

[anfos]

Regarding forks, you need adjust the air pressure to set your sag to around 30% of the travel. Then check that you are using at least 90% of the travel on the hardest hits. If you are not using most of the travel of the fork, with correct sag, then you may need to remove a volume spacer and try again. If you are blowing through all of the travel with correct sag then you will need to add a volume spacer. Tire air pressure sounds about right. Riding style/experience can also play a part in the problems you describe.

The XCR Suntour doesn't have any adjustable volume spacers and the sag is set correctly. Could it be something to do with oil or maybe it's just a stiff fork by nature? I can try 70 psi though.

 

[fenwick458]

I think the 30psi in the front tyre may be exacerbating this problem

what sort of stuff are you riding?

 

[anfos]

I think the 30psi in the front tyre may be exacerbating this problem

what sort of stuff are you riding?

At the moment non-technical fire roads, so no downhill or anything like that, most have moderate size stones and I drop the psi to ~20 on the front (which works fine). I guess it's normal for the fork to not compress when doing tarmac and using 30 psi on the tire and 80 on the fork?
Still I feel like the forks are quite stiff at 80 psi and I need to stand up to compress them properly, although I don't have anything else to compare to as it's my first EMTB.

 

[Gary]

Just intentionally move your weight further forwards when cornering. assuming you do realise you need to be stood up not seated whenever you require additional cornering grip. (the only exception being climbing)

 

[anfos]

Yeah but what about when sitting down and taking flat turns? Would lowering psi on the fork make it less stiff or should I experiment with tire pressures only? I don't think I need 80 psi for the rides I do since there are no jumps or anything like that but not sure how low I can go? Thanks!

 

[Mikerb]

I think your fork and tyre pressures are red herrings as far as applying more weight through the front wheel is concerned. If you remain sat in the saddle you are always likely to be weighting the rear wheel more than the front and extending the stem will have little impact on that.
To slightly fine tune the front to rear weight balance on your bike it largely depends where your hips are since they form the centre of your mass, so sliding the saddle forward on its rails will move that mass forward a little. After that it is really up to you to shift your position on the bike to apply more weight to the front of rear wheel and you can only do that effectively if you are stood on the pedals rather than sat on the saddle. Note as well that once stood on the pedals just rotating your feet forward or heel down on the pedals can make a big difference to front to rear weight balalnce on the bike.
I suggest you go back to the original stem
You say the fork SAG is set correctly..............how?? If you stand on the pedals to set your fork SAG ( the correct way) but meanwhile you are primarilly only riding on the flat sat in the saddle it is likely set with too much pressure. Reset you fork SAG whilst in the seated position. If you progress to riding more lumpy trails and/or downhill trails then you may wish to reset it ( probably with a higher pressure).
Note, the geometry of a trail mtb is very different to a road bike. The seated riding position is much more upright with almost equal weight on the saddle and bars/arms. It is that balanced starting point that enables you to be more flexible in adjusting your weight balance slightly either bringing your torso more upright or leaning on the bars a little more. You certainly do not want to be riding with too much weight on the bars/your arms otherwise the rougher terrain will kill your wrists and shoulders. You arms need to be slightly bent at the elbow to enable them to act as shock absorbers.
Finally if you still have trouble on turns...even on fireroads and similar, you need to learn how to corner by leaning the bike whilst you stay more upright with your weight down through the outside pedal and your hips twisted into the turn.........again, not a technique easy to do if sat in the saddle.

 

[RustyMTB]

Yeah but what about when sitting down and taking flat turns? Would lowering psi on the fork make it less stiff or should I experiment with tire pressures only? I don't think I need 80 psi for the rides I do since there are no jumps or anything like that but not sure how low I can go? Thanks!

Try it, see how you get on, why not? Go out with a shock pump, let 5psi out ata time for example & see how it feels. You can always put the air back in. The 30 psi advice you've received is good, it's deffo on the high side for riding around on fire roads.

 

[Gary]

Yeah but what about when sitting down and taking flat turns?

You can still alter your weight bais on the bike and weight the front tyre when seated. but if you seriously need more grip why would you still be sat down?
lower fork pressure is going to lower front end support and your fork is pretty basic so has little in the way of compression damping or support already. a soft divey fork is pretty much the opposite of what you want when weighting your front tyre on a flat gravel turn. Gravel bikes don't even have suspension.

If you're new to mtb and want to cross over you should maybe consider going on am mtb skills course. You're not likely to get great advice on a forum where no one can see what you're actually doing on the bike.

 

[anfos]

Thanks for the great suggestions! The Gravel bikes are so light and agile since they have a different geometry compared to emtb's which is the main issue I'd imagine for what I am describing but for a good reason since emtbs are very stable when going downhill with that wheelbase/chain stay length and fork rake. I will experiment with tire pressures and get the saddle a bit more forward and see how it goes

 

[Gary]

Sorry mate. But now you're just looking for excuses.
You don't honestly believe a lightweight gravel bike with 35-40mm tyres and no suspension will have more grip on a loose flat fire road corner than an heavy FS Emtb with 2.5" (60mm) tyres?
Regardless of geometry differences. The Emtb will have more grip than the gravel bike. The main thing here is going to be that YOU need to get used to the different handling and being less of a passenger. You'll get there one way or another so long as you keep at it.

 

[Wheels]

Ill preface this by saying im lazy…that said- i bought a battery powered bike pump so i can air up quickly after airing down when i get to the trails. Makes it easy to experiment with air pressures on the ride. Again….im lazy.