Mobie25 45mm gives minimal depression - should it be tuned?

[Fandomii]

Hi folks,

I'm riding with a new SR Suntour Mobie25, 45mm travel front fork on a speed pedelec (28mph/45kmh). Vast majority of my time is on asphalt. I find that when I do some hard stops, I do not feel the fork depress much. In my previous speed pedelecs a hard stop like that would mean a substantial sink and recoil (they were using RockShox Paragon 65mm). Is it the 20mm less travel that I missing or is it a configuration I can tune?

I have currently the Rebound and preload set both at "medium"... would it be prudent to tune one of those to create a bigger depression on hard stops for asphalt riding?

Thank you and looking forward to your advice!

 

[Stefan Mikes]

Hi folks,

I'm riding with a new SR Suntour Mobie25, 45mm travel front fork on a speed pedelec (28mph/45kmh). Vast majority of my time is on asphalt. I find that when I do some hard stops, I do not feel the fork depress much. In my previous speed pedelecs a hard stop like that would mean a substantial sink and recoil (they were using RockShox Paragon 65mm). Is it the 20mm less travel that I missing or is it a configuration I can tune?

I have currently the Rebound and preload set both at "medium"... would it be prudent to tune one of those to create a bigger depression on hard stops for asphalt riding?

Thank you and looking forward to your advice!

Only work with the Preload please. Rebound is controlling how fast the suspension recovers from the compression.

The rule for the Preload setup is that if you just sit (stationary) in full clothes on your bike, the fork should dive maximum 20% of the travel. For a 45 mm travel fork that would be just 9 mm, which is very little.

The function of the "city" suspension is rather to damp the road vibration than handling big holes .

 

[AHicks]

Only work with the Preload please. Rebound is controlling how fast the suspension recovers from the compression.

The rule for the Preload setup is that if you just sit (stationary) in full clothes on your bike, the fork should dive maximum 20% of the travel. For a 45 mm travel fork that would be just 9 mm, which is very little.

The function of the "city" suspension is rather to damp the road vibration than handling big holes .

I agree with all, but would add that the suspension SHOULD bottom out on occasion when set up properly for the conditions you ride most. This is the ONLY way you can confirm the entire suspension is being used. There is no point riding around on the top half of the suspension because it's set too stiff.....

 

[Stefan Mikes]

but would add that the suspension SHOULD bottom out on occasion when set up properly for the conditions you ride most. This is the ONLY way you can confirm the entire suspension is being used. There is no point riding around on the top half of the suspension because it's set too stiff.....

I cannot agree with you on this. A properly tuned suspension never works more than 75-80% of the available travel.
My recent incarnation of Vado 6.0 has the same suspension fork as the OP is using (only my version has an older name). It never bottoms out yet it ensures excellent smoothing out of road vibration including very dilapidated asphalt or gravel.

With short travel coil suspension, reducing Preload will only result in taking more of available travel by the rider's own weight.

 

[AHicks]

I cannot agree with you on this. A properly tuned suspension never works more than 75-80% of the available travel.
My recent incarnation of Vado 6.0 has the same suspension fork as the OP is using (only my version has an older name). It never bottoms out yet it ensures excellent smoothing out of road vibration including very dilapidated asphalt or gravel.

With short travel coil suspension, reducing Preload will only result in taking more of available travel by the rider's own weight.

We'll need to agree to disagree here I guess. I did mention "conditions most frequently traveled" which made no mention of "very dilapidated asphalt or gravel". Those conditions are clearly going to need a stiffer suspension set up.

Been messing with off road type suspensions (tuning hyd. shocks) a VERY long time (snowmobiles, quads, Atv's, dirt bikes, etc), so I do have a clue regarding how they work, and how to make them work for me. That in mind, clearly there may be others with different thoughts than my own. I'll admit that, but wasting 20+% of a good suspension's travel seems like quite a waste from where I'm sitting. If that's the way you want to set YOURS up, go for it....

 

[Stefan Mikes]

The problem with the Mobie fork is you cannot utilize the whole travel regardless the Preload.

It is the spring rate that controls the suspension fork performance here.

Even the travel of long air forks cannot be fully utilized unless the rider does jumps on singletrack.

 

[fooferdoggie]

Hi folks,

I'm riding with a new SR Suntour Mobie25, 45mm travel front fork on a speed pedelec (28mph/45kmh). Vast majority of my time is on asphalt. I find that when I do some hard stops, I do not feel the fork depress much. In my previous speed pedelecs a hard stop like that would mean a substantial sink and recoil (they were using RockShox Paragon 65mm). Is it the 20mm less travel that I missing or is it a configuration I can tune?

I have currently the Rebound and preload set both at "medium"... would it be prudent to tune one of those to create a bigger depression on hard stops for asphalt riding?

Thank you and looking forward to your advice!

I have the paragon too and never quite bottomed it out. but with only 60mmyou may just run out. the paragon never handled much in the way of hards bumps it worked best on the fine stuff.

 

[Stefan Mikes]

I have the Rock Shox Paragon Gold RL on my hub motor e-bike. That air fork has never bottomed out for me. Regarding the performance: nothing special and I would even say disappointing.

 

[AHicks]

I have the Rock Shox Paragon Gold RL on my hub motor e-bike. That air fork has never bottomed out for me. Regarding the performance: nothing special and I would even say disappointing.

I've tried a couple of inexpensive air shocks now, and have a similar opinion. An inexpensive air shock has nothing over a decent straight spring suspension (with proper pre load) while riding on pavement and hard pack surfaces. When it comes to rougher gravel (not big rocks) and pavement that's totally shot, I've found it easier to run bigger tires (I like the Schwalbe Super Moto X) in the 2.4 and 2.8" sizes, running 20psi in front and 25 in back. That REALLY takes the vibration under control - without much of a decrease in rolling resistance. My opinion - Al

 

[Stefan Mikes]

I've tried a couple of inexpensive air shocks now, and have a similar opinion. An inexpensive air shock has nothing over a decent straight spring suspension (with proper pre load) while riding on pavement and hard pack surfaces. When it comes to rougher gravel (not big rocks) and pavement that's totally shot, I've found it easier to run bigger tires (I like the Schwalbe Super Moto X) in the 2.4 and 2.8" sizes, running 20psi in front and 25 in back. That REALLY takes the vibration under control - without much of a decrease in rolling resistance. My opinion - Al

You are very right regarding the tyres. I was on a demanding group ride today. We had to ride a long segment on rough cobblestones in the forest. I can say my "Mobie" fork did the work (plus 2" tyres at 2.8 bar). Nothing could, however, match my brother riding a full e-MTB. Yes, his full suspension worked. However, it was the 2.6" tyres at 1.4 bar that made my brother ride the cobblestone "full throttle"!