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Interactive Ramp Rate Comparison with Graph

Ramp Rate Graph Blog

Ramp Rate Graphing Example

To help our clients better understand volume spacing and ramp rate we built an interactive google sheet.

This google sheet may not work with all browsers and navigation – if you find issues please let us know and we can help you navigate as needed.

Ramp Rate Comparison: How It Works

In short, viewers are invited to modify Rider Weight as well as choose Sag and Volume Spacers (the white boxes) for up to three setups. This will produce both a chart of PSI at travel percentage as well as a comparative graph with the three series for review.

Now we don’t claim these numbers are “go-to” for your setup – rather they are a reasonably accurate comparison to help you visualize how you can modify your air suspension. This example allows you to visualize differences modifying Sag % (15, 18 or 20%) and Volume Spacing (0-5).

What you’ll notice is how relatively small variations can make a big difference. Particularly in the 60% to bottom out portion of travel.

We hope the additional understanding of how the air system is actually behaving will help riders better modify setup to hit their goals.

After working with the google sheet you can read more below to better understand what the graph shows and why as well as the formulas and reasoning we’ve used.


NOTE: Mobile Users – most mobile applications will require opening the sheet in Google’s App using the link below (but we suggest you check it out on your computer for full functionality)

Ramp Rate Comparative Graph Google Sheet

More About Ramp Rate Comparison

Did you see how the ramp rates vary depending on setup? Some changes and the series are very close to each other, while other changes make large swings.

That’s why its’ important to have some basic ideas, or access to a team to help you determine what your suspension is actually doing versus what you’d like it to be doing.

Each point on these graphs represents an “instant” as the air suspension is either rebounding to extension or continuing compression based on load. Understanding the ramp rate will help you fine tune suspension, particularly on components without compression controls.

Forks and shocks with compression controls offer another level of performance hydraulically damping (slowing) the shaft input adding resistance with the air spring. Understanding how to setup compression to balance small bump compliance, mid-stroke support and bottom out can make a big difference in the direction your setup takes.

What Does Ramp Rate Change

How much pressure your suspension produces effects support. Without enough support (too low of PSI) the suspension will sit too deep “eating” up more suspension travel then required by the terrain. Too much support tends to produce a harsh ride as the bike skips across trail.

Ramp Rate effects bottom out and total amount of travel used. With too little air pressure to resist the compression riders suffer hard bottom out, excessive dive, etc. Too much pressure will limit amount of available travel. Remember to mentally review your ride when you compare travel – just because you have the travel doesn’t mean you’re always going to use it. Riding in steep terrain or smooth lines often use less travel than say, slamming straight into a curb.

Using this graph you will have an idea of changes available to you with ramp rate. If the bike “is close” minor sag or volume spacing differences may help with the dial in along with using compression controls if available. If you need larger changes this graph can help you visualize directions that will make bigger impacts.

Other Factors on Setup

So you’ve got your sag, volume spacing and compression pretty good, or even really good in portions of the travel. But, you’re still struggling to really get that “dial in”?

There are other factors to consider, and frankly few “magic bullet” options. Let’s look at some of the common culprits.

Poor Small Bump Compliance

Too much air pressure for your ground speeds is a common cause of a bike skipping across the trail. Tip-toeing down trail tends to be hard on suspension as well. Sometimes, as counter intuitive as it may sound, a bit more speed will smooth out your ride.

Remember force is mass times acceleration – so to add some force to drive the suspension speed is your friend.

Other factors to consider include rim and wheel build spec based on your size and ground speeds. Some rims are very stiff and take pretty high forces to be compliant.

Are you a very light rider? Or medium weight and medium ground speed? Having your wheels built to accommodate you will dramatically help with small bump compliance and traction.

Air pressure comes into play on both poor small bump compliance as well as higher speed “shouldering” issues.

Un-Damped Air Springs

Your fork and rear shock have rebound and compression dampers. But, you know what doesn’t? Your tires.

Remember how hard it was to dial in suspension for Plus tire bikes? With such large masses of air the tires became very efficient secondary suspension but without the ability to really be tuned.

Wider rims and higher volume tires, although not the plus size the marketeers all said we’d be running by now – just sayin – sometimes the hype is just hype eh, but wider rims and higher volume tires made this secondary suspension more of a factor.

Luckily riders have access to different sidewalls which help to damp the tire’s air spring. Rubber is an effective vibration isolator and the additional sidewall technologies help control terrain inputs through the wheels and into the suspension.

Setup & Tune

One of the things we pride ourselves on is unmatched after sales service. Helping client’s take their setups from “decent” to “dialed in” is truly gratifying. Is bottom out, ramp rate, rebound, compression and how they interact confusing? No problem. When you purchase a bike, suspension or Pro Tune suspension our team is here to help you. We can walk you through what the concepts mean and help you articulate what’s working well and where adjustments may be needed.

Our Pro Tune Suspension is a popular option for riders of all levels. Taking the industry leading FOX suspension and narrowing the performance window for individual riders based on ground speed, aggression, riding setup, terrain, goals, etc means that every click of compression or rebound has a narrower adjustment window. Each click has more minute adjustment allowing a more precise dial in.

Questions? Call, chat or email our team today!


Formulas and Concepts for Ramp Rate Comparison

Some insight on the concepts and formulas we used to produce this graph.

Suspension setup has a couple quirks that muddy the water conceptually.

We work with PSI values at full extension during setup to achieve a specific sag. At the sag point, where the suspension settles based on weight, the air pressure has increased from the PSI at full extension (the value we read). Using the same air piston size to support a given weight requires a certain pressure is achieved no matter at what point in the sag.

For our example rather than working with the starting PSI (at full extension) we are using a calculation to determine approximate PSI at sag. This calculation is based on rider weight and starting PSI averages between FOX & Yeti’s FOX 38 170mm setup for 18% sag.

Once we have the PSI at 18% sag with 2 volume spacers we are able to extrapolate a variety of different setups using the support PSI in the proper configuration.

These setup numbers are calculated using volume changes as the fork is compressed in ratio with the defined PSI times Volume at defined Sag. This is done with Boyle’s Law of Pressure1 x Volume1 = Pressure2 x Volume2 which becomes Desired PSI = KnownPressure1 x KnownVolume1 / KnownVolume2

Now, these numbers in the real world would be effected by heat and a handful of other variants that aren’t critical to our reference graphs. Since this is a conceptual visualization for teaching a concept our numbers provide reasonable accuracy.

New Bike Suspension Setup Concepts

New Bike Suspension Setup Concepts

Learn more about setting up your bike’s suspension. At BikeCo.com we pride ourselves on after sales service and helping clients dial in their new bike or Pro Tune suspension is one of our favorite tasks.

Check out this video were Nate goes through some basics of MTB suspension and commonly posed questions during setup.

See the links below for some of the tools and bits mentioned to help you get your setup just right.

Tools to make your MTB Suspension Setup Easier:

FOX Digital Pump, 350 PSI

FOX 350 PSI Digital Shock Pump

FOX Chamferless Sockets

FOX Chamferless Top Cap Sockets

 

FOX Fork Volume Spacers

FOX Volume Spacers

 

FOX X2 Volume Spacers (3 rings)

FOX X2 Volume Spacers

FOX DPX2 Volume Spacer Kit

FOX DPX2 Volume Spacers

 

 

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BikeCo Tips & Tricks: Understanding Rear Shock Negative Air Chamber

Understanding Rear Shock Negative Air Post

BikeCo Tips & Tricks: Understanding Rear Shock Negative Air Chamber

A fairly common question is “why does my rear shock lose air when I check it?” While there are mechanical issues that may cause air loss not pre-charging a pump or understanding how the negative air chamber works are more often the culprit.

Continue reading BikeCo Tips & Tricks: Understanding Rear Shock Negative Air Chamber

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BikeCo Tips & Tricks: Basic MTB Suspension Setup

MTB Suspension Setup Video

BikeCo Tips & Tricks: Basic MTB Suspension Setup

2020 brought a lot of new faces to MTB. We’re stoked to see more people benefit from the sport we all love. That said, a lot of shops simply can’t support rider development like we can. So, here’s a video & blog going through Basic MTB Suspension Setup.

We’ll look at sag, rebound, volume spacing, compression as well as high and low speed damping.

Continue reading BikeCo Tips & Tricks: Basic MTB Suspension Setup

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PreCharging a Suspension Pump – BikeCo Tips & Tricks

PreCharge Pump Blog Image

PreCharging a Suspension Pump – BikeCo Tips & Tricks

Let us show you how to precharge a suspension pump for the most accurate air suspension setup.

Many of our clients, and all of our racers, are looking to really dial in suspension. In order to accomplish this it is important to make minute adjustments to air pressure. This blog and video illustrate what’s happening in your air spring and why precharging a suspension pump is so important.

 

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Install Fork Volume Spacers – BikeCo Tips & Tricks

fork volume spacer bikeco blog

Install MTB Fork Volume Spacers

Want to increase or decrease the ramp rate on your fork? You can easily modify the ramp rate with volume spacers.

Disclaimer – If you doubt your mechanical ability utilize a professional resource. Suspension is critical to performance and your safety.

This video assumes your fork is in good working condition. If you suspect any issues such as “suck down”, or an over pressurized negative air chamber, it is important you use a qualified resource.

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Install Shock Volume Spacers – BikeCo Tips & Tricks

BikeCo Tips and Tricks Rear Shock Volume Spacer Install

Install MTB Shock Volume Spacers

Want to increase or decrease the ramp rate on your MTB shock? You can easily modify the ramp rate with volume spacers.

Disclaimer – If you doubt your mechanical ability utilize a professional resource. Suspension is critical to performance and your safety.

This video assumes your shock is in good working condition. If you suspect any issues such as “suck down”, or an over pressurized negative air chamber, it is important you use a qualified resource.

 

Continue reading Install Shock Volume Spacers – BikeCo Tips & Tricks

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Coil Spring Tuning Basics

7 23 19 Yeti SB165 T2 X01 Complete 1

Coil Spring Tuning Basics

With the launch of the new Yeti SB165 we’ve had a lot of questions. Here we go with some Coil Spring Tuning Basics.

Some very basic principals to start with here.

Coil springs are rated by the weight that creates an inch of spring compression. So a 400lb spring requires 400lbs to compress the first inch and would take 800lbs to compress two inches. However, coil springs are not produced to “exact” standards. That is to say if a coil is offered in say 50lb increments ( example: 350, 400, 450) 400lb spring may actually we anywhere from 376 to 425lbs. That’s a pretty wide range and most quality spring manufactures will have a slightly tighter tolerance, but that’s the concept.

Coil springs are also measured by total length as well as available stroke. Running a coil that is too long or short in either measurement can create problems.

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Confidence with Compression: Adjusting your fork

7 15 19 Compression and Confidence

Confidence with Compression: Adjusting your fork

Confidence with Compression – sort of a vague title right? Am I gaining confidence on trail from compression? Am I confident adjusting my compression? Well, both.

The abridged back story: I had a chance to move further south. BikeCo’s website has been growing at a rate that I can now work remotely mostly and come up to the shop a couple times a week. Anyhow – for the first time since I started bikes I’m consistently riding trails I don’t know. This presents some really fun challenges particularly as I tend to ride solo most the time.

Now I didn’t move and decide I was one of our pro riders looking for the most ridiculous lines possible. Nor did I move and decide I was going to find every gravel trail to take my SB130 on. I’m riding the same basic level of trails but the unknown adds quite a bit to riding. Continue reading Confidence with Compression: Adjusting your fork

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Front End Support – Fork Air, Volume & Compression

Front End Support – Fork Air, Volume & Compression

Between our BikeCo Pro Tune services as well as working with some of the fastest racers in MTB we get a lot of questions regarding suspension tuning. Modern forks offer more ways than ever to dial in your ride. Getting the right front end support with fork air, volume and compression improves tracking, ride quality, dive, and how your bike performs in the chunk.

Recently BikeCo Pro Rider Cody Kelley was in town working with Joe Binatena on the 2019 Alchemy Arktos 29. It was an interesting opportunity to sit down and listen to Cody and Joe discuss setup. Continue reading Front End Support – Fork Air, Volume & Compression