Forum Hot Seat - Dave Camp, RockShox Design Engineer

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jeff.brines
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jeff.brines 11/19/2015 3:46pm
11/19/2015 3:46pm
I have a lot of questions.

1) How many bike parts did you personally break this year?

2) Does the ground make any screaming noises when you unleash your DC Special cornering ability upon it?

3) In one sentence, what is your life's motto?

4) Describe your most expensive crash...

5) Has Ranger Camp ever needed to chase you down for overly aggressive riding?






PS Would my turbo snowmobile beat your supercharged miata in a straight line?
eldsvada
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eldsvada 11/19/2015 3:48pm
11/19/2015 3:48pm
iceman2058 wrote:
Yo Dave! Have you (or anybody else to your knowledge) experimented with dual-rate springs for MTB suspension? Everybody is always looking for small bump compliance +...
Yo Dave!

Have you (or anybody else to your knowledge) experimented with dual-rate springs for MTB suspension? Everybody is always looking for small bump compliance + big hit ramp-up...could dual spring rates help address that need, or am I missing something?



Dave_Camp wrote:
I think a few bike suspension companies have played with dual-rate springs, but no one has been able to make them work. Not sure why. I...
I think a few bike suspension companies have played with dual-rate springs, but no one has been able to make them work. Not sure why. I think springs are pretty hard to make in general, and adding another tuning option to a rear shock might be difficult for frame manufacturers and people to understand.

If you think about it- the regular coil and bottom out bumper are already a sort of dual rate spring- just right at the end of stroke you get a massive increase in force.

Also- air springs are generally adjustable in this manner by using volume reduction.
Actually, the RS sector DP coil had a double rate spring. In had one of those myself and it was great, all though only in the medium spring rate, the soft spring ramped way too quick.

sean08
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sean08 11/19/2015 4:00pm
11/19/2015 4:00pm
Ooh,

You know anything about test tracks in Durango? This place was a bunch of jumps on single track that was supposedly devoted to rock shox testing.

History? Personal stories? No idea what Im talking aboot?
kc358
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kc358 11/19/2015 4:51pm
11/19/2015 4:51pm
With current tokens/bands both bottom out (progression) and spring rate are affected, so if you need a stiffer spring you will unfortunately suffer from mid-stroke harshness. Do you see Rock Shox making a system to separate these adjustments?
kc358
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kc358 11/19/2015 5:08pm
11/19/2015 5:08pm
iceman2058 wrote:
Yo Dave! Have you (or anybody else to your knowledge) experimented with dual-rate springs for MTB suspension? Everybody is always looking for small bump compliance +...
Yo Dave!

Have you (or anybody else to your knowledge) experimented with dual-rate springs for MTB suspension? Everybody is always looking for small bump compliance + big hit ramp-up...could dual spring rates help address that need, or am I missing something?



Ramp is much better controlled by frame design. Adding ramp to the spring and not the damping causes bad performance characteristics. It has been tried in motorcycle forks and shocks and abandoned for bad performance. In fact, some designs that have high praise now use progressive end damping with a straight rate spring in forks. Shocks work well with a progressive linkage design that ramps spring and damping together.
Plus, the springs are harder/more expensive to make and makes choosing the right one more difficult.
Dave_Camp
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Dave_Camp 11/19/2015 5:41pm
11/19/2015 5:41pm
gbil wrote:
Hi Dave, are there any plans to add remote lock on option on a monarch rt3/plus rc3 or a vivid air ? seems like a very...
Hi Dave,

are there any plans to add remote lock on option on a monarch rt3/plus rc3 or a vivid air ? seems like a very
logical add on for today's bikes/tracks.

thanks !
Smile
Dave_Camp
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Dave_Camp 11/19/2015 5:43pm
11/19/2015 5:43pm
eldsvada wrote:
Actually, the RS sector DP coil had a double rate spring. In had one of those myself and it was great, all though only in the...
Actually, the RS sector DP coil had a double rate spring. In had one of those myself and it was great, all though only in the medium spring rate, the soft spring ramped way too quick.

Nice- I did not know that... I think a progressive fork spring might be easier to do since it's not having to interact with a frame linkage.
Dave_Camp
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Dave_Camp 11/19/2015 5:44pm
11/19/2015 5:44pm
sean08 wrote:
Ooh, You know anything about test tracks in Durango? This place was a bunch of jumps on single track that was supposedly devoted to rock shox...
Ooh,

You know anything about test tracks in Durango? This place was a bunch of jumps on single track that was supposedly devoted to rock shox testing.

History? Personal stories? No idea what Im talking aboot?
I don't know about any secret test tracks in Durango... HB might if you can find him.
Dave_Camp
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Dave_Camp 11/19/2015 5:47pm
11/19/2015 5:47pm
kc358 wrote:
Ramp is much better controlled by frame design. Adding ramp to the spring and not the damping causes bad performance characteristics. It has been tried in...
Ramp is much better controlled by frame design. Adding ramp to the spring and not the damping causes bad performance characteristics. It has been tried in motorcycle forks and shocks and abandoned for bad performance. In fact, some designs that have high praise now use progressive end damping with a straight rate spring in forks. Shocks work well with a progressive linkage design that ramps spring and damping together.
Plus, the springs are harder/more expensive to make and makes choosing the right one more difficult.
Agree. Ramp should be controlled by frame linkage. But sometimes a frame or rider needs more ramp (or less) and adding tokens is cheap, easy and accomplishes similar end result (limiting harsh bottom outs) vs building a new linkage.
Dave_Camp
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Dave_Camp 11/19/2015 5:50pm
11/19/2015 5:50pm
kc358 wrote:
With current tokens/bands both bottom out (progression) and spring rate are affected, so if you need a stiffer spring you will unfortunately suffer from mid-stroke harshness...
With current tokens/bands both bottom out (progression) and spring rate are affected, so if you need a stiffer spring you will unfortunately suffer from mid-stroke harshness. Do you see Rock Shox making a system to separate these adjustments?
Not currently. Most people don't experience too much mid-stroke harshness with air-springs. If anything air-springs are a bit soft in the mid-stroke (vs coil with same bottom out force).

I think it would add a great deal of complexity and expense to be able to separate adjustments to the air spring as you are suggesting.

Dave_Camp
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Dave_Camp 11/19/2015 5:52pm
11/19/2015 5:52pm
jeff.brines wrote:
I have a lot of questions. 1) How many bike parts did you personally break this year? 2) Does the ground make any screaming noises when...
I have a lot of questions.

1) How many bike parts did you personally break this year?

2) Does the ground make any screaming noises when you unleash your DC Special cornering ability upon it?

3) In one sentence, what is your life's motto?

4) Describe your most expensive crash...

5) Has Ranger Camp ever needed to chase you down for overly aggressive riding?






PS Would my turbo snowmobile beat your supercharged miata in a straight line?
go home Jeff.
spazo
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spazo 11/19/2015 6:30pm
11/19/2015 6:30pm
Do you think we'll ever see a coil fork option for the AM/Enduro (27.5/29) market?
sean08
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sean08 11/19/2015 6:54pm
11/19/2015 6:54pm
sean08 wrote:
Ooh, You know anything about test tracks in Durango? This place was a bunch of jumps on single track that was supposedly devoted to rock shox...
Ooh,

You know anything about test tracks in Durango? This place was a bunch of jumps on single track that was supposedly devoted to rock shox testing.

History? Personal stories? No idea what Im talking aboot?
Dave_Camp wrote:
I don't know about any secret test tracks in Durango... HB might if you can find him.
Hey, thanks dude. I was hoping for a cool John To mac story or something, that's ok though. There jumps there get burly quick, and deserve a little recognition.

I dunno any HBs, but thanks for the direction.
kc358
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kc358 11/19/2015 6:57pm
11/19/2015 6:57pm
kc358 wrote:
With current tokens/bands both bottom out (progression) and spring rate are affected, so if you need a stiffer spring you will unfortunately suffer from mid-stroke harshness...
With current tokens/bands both bottom out (progression) and spring rate are affected, so if you need a stiffer spring you will unfortunately suffer from mid-stroke harshness. Do you see Rock Shox making a system to separate these adjustments?
Dave_Camp wrote:
Not currently. Most people don't experience too much mid-stroke harshness with air-springs. If anything air-springs are a bit soft in the mid-stroke (vs coil with same...
Not currently. Most people don't experience too much mid-stroke harshness with air-springs. If anything air-springs are a bit soft in the mid-stroke (vs coil with same bottom out force).

I think it would add a great deal of complexity and expense to be able to separate adjustments to the air spring as you are suggesting.

I'm more in tune with the motocross world I guess, where mid-stroke harshness is the biggest issue with the air forks. They start ramping up there and you get a spike rather than smooth, plush suspension like coil.

Showa and KYB have both employed multiple air chambers, though neither have utilized them to control spring rate vs progression.
pmiska
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pmiska 11/19/2015 7:14pm
11/19/2015 7:14pm
Dave,

How closely do you work with the different OEMs on tuning dampers for a given bike? When you do come up with a tune that is liked and agreed to, is there a mastering process prior to hitting production?

I work on automotive suspension myself, and this is perhaps one of the greatest challenges for us, reproducing what our dynamics team likes in hand built shocks, and reproducing it for mass production. I wonder if at bicycle industry volumes this is a similar issue.

That said, what kind of annual production volumes do you see for your high runner products?

We do often marvel at the things the sporting industry can get away with technology wise, there is always much to learn from bike technology. It's always funny to see how we lead on some things, and the cycling/sport industry leads on others... The volume scaling is the one thing that I always come back to whenever people ask me why we can't do something in cars that they have on their bike.

cheers!
-p
Roots_rider
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Roots_rider 11/19/2015 8:07pm
11/19/2015 8:07pm
iceman2058 wrote:
Yo Dave! Have you (or anybody else to your knowledge) experimented with dual-rate springs for MTB suspension? Everybody is always looking for small bump compliance +...
Yo Dave!

Have you (or anybody else to your knowledge) experimented with dual-rate springs for MTB suspension? Everybody is always looking for small bump compliance + big hit ramp-up...could dual spring rates help address that need, or am I missing something?



Dave_Camp wrote:
I think a few bike suspension companies have played with dual-rate springs, but no one has been able to make them work. Not sure why. I...
I think a few bike suspension companies have played with dual-rate springs, but no one has been able to make them work. Not sure why. I think springs are pretty hard to make in general, and adding another tuning option to a rear shock might be difficult for frame manufacturers and people to understand.

If you think about it- the regular coil and bottom out bumper are already a sort of dual rate spring- just right at the end of stroke you get a massive increase in force.

Also- air springs are generally adjustable in this manner by using volume reduction.
Dual rate Ti Spring

http://www.lite-spring.com/#!product/prd1/4292561245/dual-rate-rear-sho…
stephan.roberts 11/19/2015 8:29pm
11/19/2015 8:29pm Edited Date/Time 11/19/2015 8:50pm
Hey Dave!

My name is Stephan Roberts and I am ME student in my junior year at Oregon Tech. I was wondering if you can offer some advice for my schooling, projects, etc.

At Oregon Tech I am pretty lucky to have a variety of engineering electives to choose from. Some of the ones I have taken/taking are a variety of composites classes, Instrumentation, vibrations, fracture materials, etc. Do you have any classes you look for on a engineer's resume? how about any classes that you prefer? I have a heavy interest in suspension (composites as well) and wouldn't want to miss out.

I also have been building a project list to help make my resume more practical and have fun outside of the classroom. I am currently the lead suspension engineer for our Fomrula SAE team. I also have done some DAQ stuff with my own mountain bike using cheap sensors and a microcontroller, along with small CNC and composite projects. Do you have any ideas or things you would like to see be done as a project? I'm always looking to play with stuff and try to make things work.

Anyways, I hope this finds you somewhere in all the comments. if there is anything you would like to add feel free. Thanks for being rad man!

- Stephan Roberts


Karabuka
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Karabuka 11/20/2015 1:59am
11/20/2015 1:59am
It might have been asked before, but is RS also going into dual circuit type of shocks, others have already done it and the benefits are clear as day?
Dave_Camp
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Dave_Camp 11/20/2015 6:26am
11/20/2015 6:26am
pmiska wrote:
Dave, How closely do you work with the different OEMs on tuning dampers for a given bike? When you do come up with a tune that...
Dave,

How closely do you work with the different OEMs on tuning dampers for a given bike? When you do come up with a tune that is liked and agreed to, is there a mastering process prior to hitting production?

I work on automotive suspension myself, and this is perhaps one of the greatest challenges for us, reproducing what our dynamics team likes in hand built shocks, and reproducing it for mass production. I wonder if at bicycle industry volumes this is a similar issue.

That said, what kind of annual production volumes do you see for your high runner products?

We do often marvel at the things the sporting industry can get away with technology wise, there is always much to learn from bike technology. It's always funny to see how we lead on some things, and the cycling/sport industry leads on others... The volume scaling is the one thing that I always come back to whenever people ask me why we can't do something in cars that they have on their bike.

cheers!
-p
We usually will do a tuning camp or at a minimum send multiple tunes/samples to the larger companies, take feedback and adjust as necessary. Usually we can get them comfortable on one of our multiple stock tunes, but if not we have done customs in the past.

I don't usually see a lot of issue with switching from samples to mass production. We usually send the OEM's factory built samples. hand built stuff generally stays with us.

Can't divulge numbers.

Yes- very interesting the differences between sporting good market and automotive.
Dave_Camp
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Dave_Camp 11/20/2015 6:28am
11/20/2015 6:28am
spazo wrote:
Do you think we'll ever see a coil fork option for the AM/Enduro (27.5/29) market?
I think other manufacturers are doing them. I don't see it as a high end product. the weight is too significant in my opinion.
Dave_Camp
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Dave_Camp 11/20/2015 6:30am
11/20/2015 6:30am
Karabuka wrote:
It might have been asked before, but is RS also going into dual circuit type of shocks, others have already done it and the benefits are...
It might have been asked before, but is RS also going into dual circuit type of shocks, others have already done it and the benefits are clear as day?
Vivid air and coil are both quasi- twin tube recirculating shocks. The benefits are there, however cost and overwhelming adjustments aren't always the best.
Dave_Camp
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Dave_Camp 11/20/2015 6:35am
11/20/2015 6:35am
stephan.roberts wrote:
Hey Dave! My name is Stephan Roberts and I am ME student in my junior year at Oregon Tech. I was wondering if you can offer...
Hey Dave!

My name is Stephan Roberts and I am ME student in my junior year at Oregon Tech. I was wondering if you can offer some advice for my schooling, projects, etc.

At Oregon Tech I am pretty lucky to have a variety of engineering electives to choose from. Some of the ones I have taken/taking are a variety of composites classes, Instrumentation, vibrations, fracture materials, etc. Do you have any classes you look for on a engineer's resume? how about any classes that you prefer? I have a heavy interest in suspension (composites as well) and wouldn't want to miss out.

I also have been building a project list to help make my resume more practical and have fun outside of the classroom. I am currently the lead suspension engineer for our Fomrula SAE team. I also have done some DAQ stuff with my own mountain bike using cheap sensors and a microcontroller, along with small CNC and composite projects. Do you have any ideas or things you would like to see be done as a project? I'm always looking to play with stuff and try to make things work.

Anyways, I hope this finds you somewhere in all the comments. if there is anything you would like to add feel free. Thanks for being rad man!

- Stephan Roberts


It sounds like you are on the right track. In school- I did an independent study in place of an elective and built a gear-box bike frame. You might be able to petition and do a study on the subject of your choice.

I would say any suspension in the future is going to be electro-mechanical, so any classes or experience you can gain integrating electronics with suspension will be extremely valuable.

Good luck!
Dave_Camp
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Dave_Camp 11/20/2015 6:39am
11/20/2015 6:39am
kc358 wrote:
I'm more in tune with the motocross world I guess, where mid-stroke harshness is the biggest issue with the air forks. They start ramping up there...
I'm more in tune with the motocross world I guess, where mid-stroke harshness is the biggest issue with the air forks. They start ramping up there and you get a spike rather than smooth, plush suspension like coil.

Showa and KYB have both employed multiple air chambers, though neither have utilized them to control spring rate vs progression.
Gotcha. Yeah- I think the Showa/KYB were advertising their chassis as the second air chamber- like if the main air spring were to fail- the air would still be trapped in the fork leg and still provide enough spring to help you get back home.
cmontjumper
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cmontjumper 11/20/2015 8:41am
11/20/2015 8:41am
Dave_Camp wrote:
Amphibious bike we made in freshman engineering class. it was rad

https://p.vitalmtb.com/photos/users/600/avatar/s1600_water_bike.jpg?129…
Hey, I too attempted to build an amphibious bike for my freshman projects class at CU! Although ours was not successful for many reasons.

I'm currently working on a Raspberry Pi powered system to data log my suspension. The first iteration will use accelerometers before and after dampening, and then I'll try to compare results. Accelerometers definitely aren't the best tool for the job, but they are cheap and will help start the project (I'm thinking the next upgrade will be linear potentiometers).

How often are do similar data logging systems get used in trail tests for prototypes? What sensors do you use for data acquisition?
Dave_Camp
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Dave_Camp 11/20/2015 9:40am
11/20/2015 9:40am
cmontjumper wrote:
Hey, I too attempted to build an amphibious bike for my freshman projects class at CU! Although ours was not successful for many reasons. I'm currently...
Hey, I too attempted to build an amphibious bike for my freshman projects class at CU! Although ours was not successful for many reasons.

I'm currently working on a Raspberry Pi powered system to data log my suspension. The first iteration will use accelerometers before and after dampening, and then I'll try to compare results. Accelerometers definitely aren't the best tool for the job, but they are cheap and will help start the project (I'm thinking the next upgrade will be linear potentiometers).

How often are do similar data logging systems get used in trail tests for prototypes? What sensors do you use for data acquisition?
We don't use a whole lot of DAQ on prototypes. We have stored files and can run them through a shock dyno.

Generally I've used linear position vs time and some accelerometer based stuff.

Sounds like a cool project!
Big Bird
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Big Bird 11/20/2015 9:40am
11/20/2015 9:40am
Yous guys are making my life hard with these popular forum topics. I may have to hire minions and pay them with bright Vital shirts. At least everyone is behaving well. Carry on...
justinb03
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justinb03 11/20/2015 11:00am
11/20/2015 11:00am
Hey there Dave,

Have you folks over at Rockshox dabbled in the black magic that is magnetorheological damping?
Since we are already integrating electronics into suspension this seems to be the natural progression.

Justin
stephan.roberts 11/20/2015 11:24am
11/20/2015 11:24am
Dave_Camp wrote:
Amphibious bike we made in freshman engineering class. it was rad

https://p.vitalmtb.com/photos/users/600/avatar/s1600_water_bike.jpg?129…
cmontjumper wrote:
Hey, I too attempted to build an amphibious bike for my freshman projects class at CU! Although ours was not successful for many reasons. I'm currently...
Hey, I too attempted to build an amphibious bike for my freshman projects class at CU! Although ours was not successful for many reasons.

I'm currently working on a Raspberry Pi powered system to data log my suspension. The first iteration will use accelerometers before and after dampening, and then I'll try to compare results. Accelerometers definitely aren't the best tool for the job, but they are cheap and will help start the project (I'm thinking the next upgrade will be linear potentiometers).

How often are do similar data logging systems get used in trail tests for prototypes? What sensors do you use for data acquisition?
A rasberry pi is definitely a great way to go on DAQ vs. my Arduino DAQ. Your sample rates and time intervals will be much smoother. Anyways, if you are balling on a budget like me I recommend looking at potentiometer sensors on alibaba.com. Basically cheap Chinese potentiometers. By having a linear potentiometer and a accelerometer you can understand (with a little calculus of course) what the suspension is doing at a particular speed and g-loading. I wish you luck!
spazo
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spazo 11/20/2015 3:19pm
11/20/2015 3:19pm
spazo wrote:
Do you think we'll ever see a coil fork option for the AM/Enduro (27.5/29) market?
Dave_Camp wrote:
I think other manufacturers are doing them. I don't see it as a high end product. the weight is too significant in my opinion.
Yeah I get it. It's a shame though. There's such a small amount of riders out there that actually appreciate coil fork performance vs those who think performance and reliability is measured in grams and an air spring. It would have been great to see the Yari offered with both spring types.

Thanks for your time and energy to help make this forum a success!
BikeEveryDay
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BikeEveryDay 11/20/2015 7:15pm
11/20/2015 7:15pm Edited Date/Time 11/20/2015 7:28pm
Hello Dave,

I'm currently a freshman at Rensselaer Polytechnic Institute in New York studying Mechanical Engineering. My dream is to have a career in the bike industry, namely frame/suspension engineering, component design, and so on. What would you recommend for me to do in order to gain industry connections, ultimately giving me opportunities to work within the bike industry? I currently work at a bike shop in the summer time, and I race collegiate downhill as well. One idea I had was to try reach out to bike companies this summer about internships for next summer (when I won't be working in the bike shop anymore). Also I am going to join the Formula SAE team at RPI, possibly specializing in frame/suspension design.

Any and all help is greatly appreciated!

Thanks,

Will Johnson

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