Enduro/gravity bike suspension and geo

[Eddy Gordo]

XC 

• 20-25mm internal width range
• Generally suited for 2-2.25″ wide tires

Trail

• 23-27mm internal width range
• Generally suited for 2.25-2.5″ tires

Enduro/dh/ freeride

• 27-35mm internal width range
• Generally suited for 2.3-2.6″ tires

Plus size

• 32-50mm internal width range
• Generally suited for 2.8-3.8″ tires

https://www.singletracks.com/mtb-gear/can-i-run-a-wide-tire-on-my-rim-mountain-bike-rim-widths-de-mystified/

[Eddy Gordo]

"The other area worth noting is the consistency of times between the 30mm and 35mm rim - much of the conventional wisdom suggests that a 2.35 tire on a 35mm rim is a less than ideal combination, but in terms of times and feel, it is hard to separate the two - it follows that wisdom in losing some side bite, but the profile of the carcass is better."

 

'If your question is: "My current rims are narrower, should I upgrade them?" In honesty, I would have to say no. If you are used to riding your current rims, why worry? Unless you have the chance to ride wider rims, you'll never know their benefits. In terms of outright performance, good geometry, suspension, and brakes are always more important"

 

"The other area worth noting is the consistency of times between the 30mm and 35mm rim - much of the conventional wisdom suggests that a 2.35 tire on a 35mm rim is a less than ideal combination"

 

https://www.pinkbike.com/news/rim-widths-comparison-test-mountain-bike.html

[Hairy]

I use the tried and tested squeeze test, first founded on old 26'ers with beefy 26x1.95" tyres back in the day.

[Headshot]

Started running my back tyre at 32psi. Rides horribly on the flat rocky stuff at Tokai but is great on the downhills. Also requires a slower rebound to compensate for the extra bounce.

[stefmeister]

Started running my back tyre at 32psi. Rides horribly on the flat rocky stuff at Tokai but is great on the downhills. Also requires a slower rebound to compensate for the extra bounce.

 

Interesting that you mention that. I never consider rebound and tyre pressure, but I do prefer the way the bike's suspension feel when I run higher pressure. Just clicked now. Running 23/30. Have run 20/23 in the past and no issues, but then again I way ~72-75.

[RiverInTheRoad]

I have found that nothing has a bigger effect on riding comfort than tyre pressure. I try to go as soft as is practical. 

 

My current setup:

 

29mm internal rims (FLOW MK3)

 

Front: DHF 29x2.5WT EXO - 1.4bar (20.3 psi)

Rear: DHR 29x2.4WT EXO - 1.5 - 1.6bar (22-23 psi)

 

With these pressures my tires get those diagonal lines which are typically from tyre squirm. They only burp (I don't really feel it that much on other trails) on extreme high g-force berms like at G-Spot. My mass is around 86kg with riding kit.

 

As mentioned tyre pressure also has a knock-on effect on your required suspension rebound setting! 

 

I have a Specialized Stumpjumper 2019 and basically followed the Bike Setup Tool on their website. Which I found was an extremely good base setting. I am on the lower end of their suggested tyre pressures.

 

PS: I measure tyre pressure with a Topeak digital gauge (floor pumps can be way out!)

Edited January 29, 2020 by RiverInTheRoad

[Headshot]

I have found that nothing has a bigger effect on riding comfort than tyre pressure. I try to go as soft as is practical. 

 

My current setup:

 

29mm internal rims (FLOW MK3)

 

Front: DHF 29x2.5WT EXO - 1.4bar (20.3 psi)

Rear: DHR 29x2.4WT EXO - 1.5 - 1.6bar (22-23 psi)

 

With these pressures my tires get those diagonal lines which are typically from tyre squirm. They only burp (I don't really feel it that much on other trails) on extreme high g-force berms like at G-Spot. My mass is around 86kg with riding kit.

 

As mentioned tyre pressure also has a knock-on effect on your required suspension rebound setting! 

 

I have a Specialized Stumpjumper 2019 and basically followed the Bike Setup Tool on their website. Which I found was an extremely good base setting. I am on the lower end of their suggested tyre pressures.

 

PS: I measure tyre pressure with a Topeak digital gauge (floor pumps can be way out!)

Yes, quite right, tyre pressure has a massive effect on comfort. I weigh in the 86kg area and find with pressures as low as yours I get too much tyre squirm especially on fast, berm filled tracks so I have to put up with higher pressures and less comfort.

 

A digital pressure gauge is my next purchase, I suspect my floor pump gauge is pretty inaccurate. 

[Headshot]

Interesting that you mention that. I never consider rebound and tyre pressure, but I do prefer the way the bike's suspension feel when I run higher pressure. Just clicked now. Running 23/30. Have run 20/23 in the past and no issues, but then again I way ~72-75.

I'm still experimenting but yesterday it felt more comfortable on the flat rocky stuff with the slower rebound. 

[Wheelie87]

I have found that nothing has a bigger effect on riding comfort than tyre pressure. I try to go as soft as is practical. 

 

My current setup:

 

29mm internal rims (FLOW MK3)

 

Front: DHF 29x2.5WT EXO - 1.4bar (20.3 psi)

Rear: DHR 29x2.4WT EXO - 1.5 - 1.6bar (22-23 psi)

 

With these pressures my tires get those diagonal lines which are typically from tyre squirm. They only burp (I don't really feel it that much on other trails) on extreme high g-force berms like at G-Spot. My mass is around 86kg with riding kit.

 

As mentioned tyre pressure also has a knock-on effect on your required suspension rebound setting! 

 

I have a Specialized Stumpjumper 2019 and basically followed the Bike Setup Tool on their website. Which I found was an extremely good base setting. I am on the lower end of their suggested tyre pressures.

 

PS: I measure tyre pressure with a Topeak digital gauge (floor pumps can be way out!)

 

"My mass is around 86kg with riding kit." ==> To when are you referring here ? Matriek?

Maybe a new digital scale will do 

 

Agree with what you say though - spot on 

[Thermophage]

4k...I run 26PSI in a Spez Elim GRID on the front and 27 PSI in the Butcher Black Diamond rear...and I weigh 73kg with a sock on.

If I run lower pressure than that, the probability of pinches (esp on the rear) is too high.

Hell...DHR2 EXO+ at 30PSI and dead...that EXO+ is poo poo for a rear tyre if you trying to haul assssss.

[RiverInTheRoad]

I purposefully stated around

 

"My mass is around 86kg with riding kit." ==> To when are you referring here ? Matriek?

Maybe a new digital scale will do 

 

Agree with what you say though - spot on 

[RiverInTheRoad]

To need those pressure you are probably very fast or extremely un-smooth. The EWS guys run those pressures.

 

4k...I run 26PSI in a Spez Elim GRID on the front and 27 PSI in the Butcher Black Diamond rear...and I weigh 73kg with a sock on.

If I run lower pressure than that, the probability of pinches (esp on the rear) is too high.

Hell...DHR2 EXO+ at 30PSI and dead...that EXO+ is poo poo for a rear tyre if you trying to haul assssss.

[Thermophage]

To need those pressure you are probably very fast or extremely un-smooth. The EWS guys run those pressures.

Some EWS guys. Most are running closer to 30PSI and inserts often.

[Jewbacca]

To need those pressure you are probably very fast or extremely un-smooth. The EWS guys run those pressures.

Do you mean he ploughs, or that he hasn't been hit by, hasn't been struck by............. (shows himself out) 

[Hairy]

Some EWS guys. Most are running closer to 30PSI and inserts often.

just come out and admit you have the grace of a bull in a china shop

[Thermophage]

Do you mean he ploughs, or that he hasn't been hit by, hasn't been struck by............. (shows himself out) 

A smooth criminal?