[Crud]

Wondering if any suspension savvy people can shed some light on something for me.

I’m in a situation where I have a 145mm and 160mm bike. I like them both a lot but probably should have a 120/130mm. So what’s the downsides of running the 145mm at around 130-135mm? The advice I get from manufacturers is “it will reduce performance” and no specifics on that.

I figured this is exactly what a lot of transition bikes do with stroke length, same with the Cannondale habit for example, so I’m unsure of the downsides if I’m looking for a firmer and poppier feel.

Especially when I look at the leverage ratios for the Hightower and tallboy. Say I had a Hightower, and wanted to run it firmer, even at 120mm I would have similar ratios start and end. So I can’t figure out how a firm Hightower would feel different.

is it an anti squat or anti rise thing? Does it involve the longer shock stroke? Geo will obviously be different what that’s not something I would care about. It only takes about 15% increase in psi, so I wouldn’t think I’d be running into high psi shock differences.

I’m just trying to see what I’m missing here.

Cheers!

 

[SouthSoundRider]

I hate squats! Leg pains for days! When my legs are burned out, that’s when anti-rise kicks in.

 

[DrYeet]

Do you mean that you'll reduce travel by swapping to a shorter stroke shock or are you just gonna stiffen things up on your current one? I'd personally inflate it more and add damping, as you'll still have some travel available, should you need it. But there aren't really any downsides aside from weighing more than the shorter travel bike.

I had to ride 200 km during a school trip on my 170/160 enduro bike, so I just pumped up the tires and suspension and it felt good.

 

[Muddysocks]

Wondering if any suspension savvy people can shed some light on something for me.

I’m in a situation where I have a 145mm and 160mm bike. I like them both a lot but probably should have a 120/130mm. So what’s the downsides of running the 145mm at around 130-135mm? The advice I get from manufacturers is “it will reduce performance” and no specifics on that.

I figured this is exactly what a lot of transition bikes do with stroke length, same with the Cannondale habit for example, so I’m unsure of the downsides if I’m looking for a firmer and poppier feel.

Especially when I look at the leverage ratios for the Hightower and tallboy. Say I had a Hightower, and wanted to run it firmer, even at 120mm I would have similar ratios start and end. So I can’t figure out how a firm Hightower would feel different.

is it an anti squat or anti rise thing? Does it involve the longer shock stroke? Geo will obviously be different what that’s not something I would care about. It only takes about 15% increase in psi, so I wouldn’t think I’d be running into high psi shock differences.

I’m just trying to see what I’m missing here.

Cheers!

If you have a shock where you can reduce the travel through spacers, (like a lot of the metric shocks) and you can keep the eye to eye the same, you can absolutely do that. The bike won´t use the very last bit of the travel so that may change the progression of the frame a bit (depending on what the manufacturer built into the very last bit of the leverage curve. ) But shouldn´t be a big deal. Most forks can be reduced in travel as well either through spacers or a new air spring. Problem is here that the fork will get shorter while the shock stays same lenght so you do make the geo a bit steeper. If your frame has a flip chip that could compensate - at the price of a lower BB.

I have been running that setup for quite a while now. Running a 170/170 mm frame at 160/~157mm. Fork reduced through spacers to 160mm, 65mm stroke shock reduced to 60mm and using an offset bushing to shorten it slightly and compensate for the shorter fork. It was a curiosity experiment that I liked so much I don´t feel like going back anytime soon. I find the bike does indeed feel a little more poppy and responsive.

Making the bike sit deeper in it´s travel by just running lower pressure will likely do the opposite of what you are looking for and make the bike a wallowy, pedal striking mess.

Making a bike sit higher in it´s travel through more pressure will make things more harsh and likely decrease traction, too. You may be able to find a sweet spot though that gives you the more poppy feel you are looking for without making things too harsh. Feel free to experiment. Air is free

 

[Crud]

Cheers. Yeah, I was going to just run more air, more compression to taste. Wasn't going to shorten stroke as I wasn't sure if that would do anything limiting that last bit entirely. An offset bushing and shorten the fork 10mm to bring the BB lower.

The skeptic in me thought the manufacturer just didn't want to admit it would work fine, and I should just get another bike. But I'm no kinematic expert.

 

[plummet]

The whole point of having less/more travel bikes is that the entire package is optomised for that travel. In theory a 120mm bike will be lighter with faster rolling tires lighter wheels. and adjusted geo and kinematics to suit.

By Just changing travel you will don't change weight or kinematics. You just make a heavy shorter travel bike.

If you want faster performance getting a lighter wheelset with lighter faster rolling tyre's will make much more actual performance increase.

 

[Crud]

If you want faster performance getting a lighter wheelset with lighter faster rolling tyre's will make much more actual performance increase.

Agreed. I have two sets of wheels for this purpose Not that frame weight worries me much since it will be trail and not XC, but the tallboy and HT also have similar weights. Hence my question is directed towards those who understand kinematics, since they seem the same from my limited knowledge.

 

[Fleas]

On my HT I can run anywhere from 130-150mm fork. I dont need tons of travel so I run a 130 fork, but I have a ~10mm-tall external lower headset bearing. So the geo is like having a 140, but with a more taut fork (very little brake dive, good pedal clearance...). I imagine it probly would feel like a dirt jumper to someone else.

-F