Dear Guest,
Please register or login. Content don't create itself!
Thank you
-
Re: Crumpton Cycles
Hi Nick,
I've been hoping you would get smoked out. Your beautiful bikes have been an inspiring motivational factor for me taking a step beyond hobby.
That you don't come from an engineering background was a surprise to me. When you write that you spent 2 years researching CF how did you go about it? Internet? Books? Guest listener at Uni?
How did you know your work was "good enough" and how long (or how many tries) did it take you to get there after buying your first fabric? Do you still have and ride that first prototype?
Thanks for sharing
Cheers
Kevin
-
Re: Crumpton Cycles
First off, I am a big fan and hope to own one of your bikes in the future.
I feel like I see more and more custom stems on the steel bikes. At some point, I also saw an integrated carbon handbar that you made. I believe on WW. Do you have any plans to make handlebars and stems in the future?
Could you say something about the different carbon sources for a custom carbon builder. Is there a problem of access to different raw materials for the custom builder?
-
Re: Crumpton Cycles
Originally Posted by
Too Tall
Nic, I've got some followup questions. For now, mind talking about what a Bad A$$ you are/were on the track and how racing influnced design?
XXX Josh
XXOOXX Josh-
I’m not sure of the racing I did influenced design or not. Maybe simply in the fact that good racing bikes were figured out long before I ever thought about building and there was plenty of example to follow? There are certain principles I follow in design that deal with weight distribution, adapting the wheel location for how a rider sits. I’m not sure my weenie racing past has helped there. It’s more a visual mathematic thing.
Originally Posted by
e-RICHIE
yo nick - thanks for doing this atmo.
what's next?
you're at about 40 or so units per annum (that's latin for per year) iirc.
do you expand production, raise the prices, and/or brand the name?
also, what are your feelings wrt a helper?
are you a loner type or can you imagine another voice in your personal space while you work?
ATMO-
I see 60 units a year for a while. Prices only change if my costs go up, for now they haven’t. How does one “brand the name”?
I am a loner pure and simple. I have recently been working with a local who I have known a while, helping him setup a paint shop and teaching him what I know about shooting carbon. He will carry my finish work. So rather than employ, I help setup a cottage. I like that. He does fantastic work. He sprayed high end custom guitars in a previous life.
Originally Posted by
edoz
Nick, lots of people (myself included at one time) think of carbon fiber as something only the big companies do with 6 or 7 figure investments in tooling and research. Giants like Trek and Specialized put a lot of effort into convincing the masses that all that engineering and equipment are required to build with carbon. Do you have any thoughts about this perception, and do you feel like it affects your business at all? Have you ever felt like small carbon builders are passed over or not given full consideration because of marketing from the big boys?
Also, do you ever want to build mountain bikes or because it sounds like you have a pretty wide fabrication skillset, combine carbon with another material, like steel or ti?
The stuff you had in Richmond was amazing. You are pretty much the reason I don't think of carbon as a big company material anymore.
I think if you are molding proprietary monocoques or sub assemblies, in house, it takes some resources. Thats framebuilding of a different kind. I am building frames from tubes. I do in house validation of certain aspects of what I do and have 2 independent houses do CEN fatigue stuff. We are golden.
I did design my own stays but that was as simple as putting pencil to paper. Laminate schedules are all theory put to test, no need for a $6M team to exorcise simple theory.
If we cracked the books on some of those larger houses we’d see their marketing budgets are far bigger than their R&D. And as an added bonus, if you consider R&D as a % of units or revenue, my R&D budget is much higher than that of a 10k unit +yr giant. Although a slanted look I’ll admit.
.
Originally Posted by
Jayme
Hi Nick,
Great to read about your journey to where you are today and I wish you continued success. Did you notice any measurable benefit from the Editor's Choice award back in '08 or does that sort of 'mainstream' recognition cause more headache?
Thanks for gettin' smoked!
Jayme
Jayme-
I don’t care what anybody says, but a 25k+ per issue dist bit like Bicycling Mag… editorial like that sells effing bikes. I will never trash that fine periodical.
Originally Posted by
Bob Ross
Hi Nick, really appreciate your doing this. Two questions:
1) Is it useful, in an instructive way -- or, for that matter, even possible -- to make any generalizations about the different joinery methods for a carbon frame? I.e., cost of entry notwithstanding, are there reasons why mitered/tacked/laminated tubes might be a preferable method versus molded "monocoque" (sic) bladder whoozamawhatsits, or the glued-tubes-&-lugs that you've discussed elsewhere on this forum?
2) Irrespective of the market opportunites, is there anything carbon offers -- let's say "performance-wise" -- that can't be achieved with another material? (And vice versa.)
Thanks.
Bob-
For my money, its more about execution of process rather than the process itself. Poor execution will result in crap regardless of the process. Execution includes design.
What tube-to-tube brings is ease of customization and increased sku’s without mega$ tooling. It also brings carbon building into the hands of small shops.
I’m gonna leave that last question because I have no quantifiable data to back anything having to do with that. I guess that was better than answering with a question?
Originally Posted by
Archibald
Yo Nick - Big fan, first time caller.
I know you've done some contract building in the past, are you still doing it & plan on continuing? What are your thoughts on the economics of one man shops building outside their own brand?
Don-
I work with Justin and Craig. That’s about it at the moment. I have talked to others but prefer to work with folks like Gaul-Cicli because they know exactly what they want and why. Mutual respect is important. I find it hard to respect pure marketing bozos with no skill. That was too much wasn’t it.
Originally Posted by
vulture
I was born in Reno too. You are closer to the future than most of us know. What about mountain bikes? Do you want to teach frame building classes?
Washoe County Medical class of ’66.
MTB, yes. I offer only 29r and only in stock sizes. M, L and XL as that’s all the bandwidth I have. And with the flood of carbon 29r hitting the streets this year, I wont bother pushing it.
Not classes so much as I am available for consultation for established frame companies of all sizes.
Originally Posted by
datas_brother
Hi Nick,
I've been hoping you would get smoked out. Your beautiful bikes have been an inspiring motivational factor for me taking a step beyond hobby.
That you don't come from an engineering background was a surprise to me. When you write that you spent 2 years researching CF how did you go about it? Internet? Books? Guest listener at Uni?
How did you know your work was "good enough" and how long (or how many tries) did it take you to get there after buying your first fabric? Do you still have and ride that first prototype?
Thanks for sharing
Cheers
Kevin
Kevin-
I was hoping to get smoked out too. Well I believe engineers are born, not made. I have met more than my share of ME, EE and CE grads that couldn’t engineer a paperclip. Truth is I am a high school dropout. But somehow attained a grade 10 engineering position with a pretty top notch network gear company. I would have easily made grade 12 but company policy required min BA for that. I can tell you that designing a 50,000 node BB access network with 3 levels of QOS and a bunch of VPNs is far more engineering than spec’n and testing a bicycle frame.
CF research, google, books and trade rags.
Originally Posted by
JBLANDE
First off, I am a big fan and hope to own one of your bikes in the future.
I feel like I see more and more custom stems on the steel bikes. At some point, I also saw an integrated carbon handbar that you made. I believe on WW. Do you have any plans to make handlebars and stems in the future?
Could you say something about the different carbon sources for a custom carbon builder. Is there a problem of access to different raw materials for the custom builder?
J-
Thanks for the kind words. Ah, the bar-stem combos. Those are beautiful. I do not make them for sale because of liability reasons. The stems I fabricated(from scratch) will survive re-entry but carbon handle bars are not so great at surviving hard crashes. I worry about people riding damaged bars. If a bar breaks and someone is hurt, I do not want to be involved.
Materials for builders are easy. Many sources for rear kits, Edge, Deda, Columbus and no name Asian stuff.
Edge, Deda and Columbus sell complete tubes sets. Mark at Paragon has nice BBs for carbon. Dry fabric, laminating resin and bagging materials are widely available via internet sales. Pre-pregs are a bit harder but totally available.
Nick Crumpton
crumptoncycles.com
Instagram
"Tradition is a guide, not a jailer" —Justin Robinson
"Mastery before Creativity"—Nicholas Crumpton 2021
-
Re: Crumpton Cycles
Nick,
thanks for the answer.
Care to share some pictures of your shop?
Cheers
Kevin
-
Re: Crumpton Cycles
Nick,
From what I've seen, and what S&S says, Calfee is the only guy out there adding couplers to carbon frames. Have you? Would you? Thoughts on couples in carbon tubes?
Thanks,
Tony
Anthony Maietta
Web Site |
Blog |
Flickr
"The person who says it can not be done, should not interrupt the person doing it."
-
Re: Crumpton Cycles
I am developing quite a strong following of women. Especially 5'2" and under cause I have a strange take on how to build those bikes
Could you expound upon this? My fiancee is 5'2" and doesn't really fit the "WSD" mold.
-
Re: Crumpton Cycles
Nick,
Any potential for a Crumpton Tandem?
Mark
-
Re: Crumpton Cycles
Nick,
Can you talk briefly about where you honed your chops relating to bike fit and handling...? Was the info passed to you or did you seek it out solo in the same way that you seem to have researched the carbon materials issues? I ask for two reasons:
1. During the fitting process you changed my saddle position in pretty big way...and took the time (a few months, if I remember right) to make sure it was the right thing to do. Maybe that's par for the course for many builders, but I'd had three "pro" fit sessions prior to yours and none of them said boo about it prior to you. Oh...and it has worked out perfectly and I thank you for not rolling over and going with the numbers the client sent you. I do, however, think that takes a certain degree of confidence.
2. The SL you built me handles great...perfectly...but does feel somewhat unique compared to the other bikes I've owned. The handling is neutral, but there's something cool about the way the bike moves that makes me wonder if you've tinkered with the center of gravity or where the two wheels are located relative to my center of mass. Fluke, or part of some kind of Crumpton ethos...?
Thanks again for the lovely bike...
-
Re: Crumpton Cycles
nahtnoj-
Thanks for the kind words. Not sure how customers perceive pricing other than no one questions it. As for pricing, I do no price based on the market but rather a on COGS and margin. Should I raise my prices? I dono.
Nick,
That's not true! I questioned your pricing when we first met. My "belief" is that your pricing low relative to what the market will bear and relative to the quality of the product you produce...as well as the time you spent fitting me. That said, I do admire your pricing philosophy of simply pricing off your cost and making what you consider to be a fair margin. So there you go...I just countered my own opinion. I just think customers would be willing to pay more money for what you do.
So my questions are..when do you think you will finish my bike? Also, will you wait to raise your prices until after mine is completed?
Thanks,
Sean
-
Re: Crumpton Cycles
Originally Posted by
datas_brother
Nick,
thanks for the answer.
Care to share some pictures of your shop?
Cheers
Kevin
Kevin-
Not much of a shutter bug here. Hence my lack of FNL. Will get on the wagon soon enough though.
Originally Posted by
anthonymaietta
Nick,
From what I've seen, and what S&S says, Calfee is the only guy out there adding couplers to carbon frames. Have you? Would you? Thoughts on couples in carbon tubes?
Thanks,
Tony
I’ve done it. It wasn’t terribly difficult although it took quite a bit of mod’n and custom tube work to make them fit. I kind of get the feeling it detracted from my bike. I’m keeping them off the menu for now.
Originally Posted by
nahtnoj
Could you expound upon this? My fiancee is 5'2" and doesn't really fit the "WSD" mold.
At a glance, the typical WSD just seems to create a compact cockpit. No regard for front end geometry and weight distribution. They make some big assumptions about women who typically are not all needing the same things. So looking at the needs of individuals helps. Proper front centers meaning shallower HTAs and longer rakes for neutral trail… Then being sure the CS are long enough to keep the front end weighted. Just about the opposite of what I have seen in WSD. Yeah?
Originally Posted by
MarkC
Nick,
Any potential for a Crumpton Tandem?
Mark
Mark-
Probably not for some time. It’s just not my forte.
Originally Posted by
BryanF
Nick,
Can you talk briefly about where you honed your chops relating to bike fit and handling...? Was the info passed to you or did you seek it out solo in the same way that you seem to have researched the carbon materials issues? I ask for two reasons:
1. During the fitting process you changed my saddle position in pretty big way...and took the time (a few months, if I remember right) to make sure it was the right thing to do. Maybe that's par for the course for many builders, but I'd had three "pro" fit sessions prior to yours and none of them said boo about it prior to you. Oh...and it has worked out perfectly and I thank you for not rolling over and going with the numbers the client sent you. I do, however, think that takes a certain degree of confidence.
2. The SL you built me handles great...perfectly...but does feel somewhat unique compared to the other bikes I've owned. The handling is neutral, but there's something cool about the way the bike moves that makes me wonder if you've tinkered with the center of gravity or where the two wheels are located relative to my center of mass. Fluke, or part of some kind of Crumpton ethos...?
Thanks again for the lovely bike...
Bryan—
It started with my time at Technosport and the Intertech line. First one has to get the simple concepts of good bike geo to a given fit and stay rooted in them. Biggest mistake I could make as a builder is to be swayed(by customers) by desires for this angle or that length without regard for how someone actually sits.
If I recall your saddle was alarmingly high for your inseam, shoe size etc. We had the luxury(queue) of a several month wait so you could experiment with my recommendations on your current bike.
No fluke, I just put the wheels where I think they should be for you.
Originally Posted by
moran
Nick,
That's not true! I questioned your pricing when we first met. My "belief" is that your pricing low relative to what the market will bear and relative to the quality of the product you produce...as well as the time you spent fitting me. That said, I do admire your pricing philosophy of simply pricing off your cost and making what you consider to be a fair margin. So there you go...I just countered my own opinion. I just think customers would be willing to pay more money for what you do.
So my questions are..when do you think you will finish my bike? Also, will you wait to raise your prices until after mine is completed?
Thanks,
Sean
Hey Sean-
When do you want it and how much do you wanna pay?? Seriously, at this point a deposit is a framset price lock.
Nick Crumpton
crumptoncycles.com
Instagram
"Tradition is a guide, not a jailer" —Justin Robinson
"Mastery before Creativity"—Nicholas Crumpton 2021
-
Re: Crumpton Cycles
Nick,
You set the standard to which I aspire.
Do you prefer to: Wet out CF before application? Infuse epoxy after laying out CF? Or some other process?
Rick G.
-
Re: Crumpton Cycles
Originally Posted by
CyclesNoir
Nick,
You set the standard to which I aspire.
Do you prefer to: Wet out CF before application? Infuse epoxy after laying out CF? Or some other process?
Rick G.
Rick-
Thanks man. I do the joinery with pre-pregs. I did start with wet-layup/vac but made the transition shortly after going full time. I think pre-pregs allow for more repeatability and consistency with less headache. Having said that, wet layup can build a nice bike. It actually opens up the process to more individuality in execution. The thing I never understood is the interest in vac infusion. Vac infusion has tremendous benefit for large parts where wet layup can be rather messy and resin pot life gets exceeded before a part can be completed/bagged. It just seem rather complex and cumbersome for such a small part. Have you tried it? Ive always been curious, do the various flow aids wreak havoc on the cosmetics?
Nick Crumpton
crumptoncycles.com
Instagram
"Tradition is a guide, not a jailer" —Justin Robinson
"Mastery before Creativity"—Nicholas Crumpton 2021
-
Re: Crumpton Cycles
Thanks for the info.
No, I haven't tried infusion - too much 'stuff' for me to take on right now. Good to hear your perspective on it.
RG
-
Re: Crumpton Cycles
Hi Nick,
when you use Prepreg, do you just oven it in a vacuum bag or do you have an autoclave? Also, how do you handle alignment? It seems heat for curing PP would soften things up a bit allowing tubes to move out of true after tacking.
Kevin
-
Re: Crumpton Cycles
Nick,
as the owner of Gaulzetti Corsa Carbonio #1 and one who had wanted one of your frames for the past three years, I must thank you for the marvelous machine you built. I am absolutely thrilled with it.
-
Re: Crumpton Cycles
Originally Posted by
datas_brother
Hi Nick,
when you use Prepreg, do you just oven it in a vacuum bag or do you have an autoclave? Also, how do you handle alignment? It seems heat for curing PP would soften things up a bit allowing tubes to move out of true after tacking.
Kevin
Kevin-
Great questions. I use and oven only. However I have a little extra going on in the bag that in increasing pressure. More intel on that later. Regardless, there are some pre-pregs out there that do very well in vac bag only. Getting a resin with good flow, a touch more resin:fiber helps. Reality is, autoclave pressures are important when laminates are thick. These days I am not dealing with anything thicker than .070”
Regarding alignment, your tubes and parts have a spec called glass transition (Tg). this is the temp at which their matrix will soften. Same goes for the adhesive used to tack and fillet your joints. I do all my bagged cooking well below this number. 25% below the lowest Tg in my case.
How did I get pre-pregs with a cure temp that much lower than the Tg of standard cured parts? I established my own cure profile on my prepregs. So instead of the 250f x60min spec, I am cooking at a much lower temp for a longer period of time. I established this by making 1”x2”x .065”, samples 10 each at a variety of temps and dwell including the original spec of 250fx60min. I do what is called a tensile flexural modulus test. Essentially this is bending to failure while documenting force and deflection. With epoxies, generally the hotter the cure, the shorter the dwell needed. I found one I am very happy with and have zero alignment or tube ovalizing issues.
Originally Posted by
jonathanb
Nick,
as the owner of Gaulzetti Corsa Carbonio #1 and one who had wanted one of your frames for the past three years, I must thank you for the marvelous machine you built. I am absolutely thrilled with it.
Jonathan-
Thanks man. I really wanted to ride that bike.
Nick Crumpton
crumptoncycles.com
Instagram
"Tradition is a guide, not a jailer" —Justin Robinson
"Mastery before Creativity"—Nicholas Crumpton 2021
-
Re: Crumpton Cycles
Originally Posted by
crumpton
snip
Regarding alignment, your tubes and parts have a spec called glass transition (Tg). this is the temp at which their matrix will soften. Same goes for the adhesive used to tack and fillet your joints. I do all my bagged cooking well below this number. 25% below the lowest Tg in my case.
How did I get pre-pregs with a cure temp that much lower than the Tg of standard cured parts? I established my own cure profile on my prepregs. So instead of the 250f x60min spec, I am cooking at a much lower temp for a longer period of time. I established this by making 1”x2”x .065”, samples 10 each at a variety of temps and dwell including the original spec of 250fx60min. I do what is called a tensile flexural modulus test. Essentially this is bending to failure while documenting force and deflection. With epoxies, generally the hotter the cure, the shorter the dwell needed. I found one I am very happy with and have zero alignment or tube ovalizing issues.
Thanks for the answer. This is getting more interesting with each post! I currently only do repairs for others and one of the reasons I don't use an oven is that you never know what Tg the adhesives the makers use to bond the metal bits have. Instead I use a room temp-curing epoxy that reaches acceptable strength after 24 hours and full strength after 7 days. I could bake it to accelerate curing but if I bake too long the matrix gets brittle. Have you ever had that happen to the matrix of the tubes when you leave them in the oven for extended periods of time?
Can't wait till follow up on how you increase bag pressure.
Cheers
Kevin
-
Re: Crumpton Cycles
Kevin-
I'd say embrittlement would come from exposure to too high of a temp as opposed to long exposure to a lower temp. We are talking hours here, not days, months or years. So while I know 3 hours at 200f wouldn't do a thing to a laminate with a Tg of 260, 6 months at 200f might.
Stay away from heat lamps for your wet stuff. You can get hot spots and combined with the exotherm of the curing epoxy itself, not only can you get embrittlement, you can start a fire.
I use a PID controlled convection oven with a +/- 1deg f variance anywhere in the oven.
Nick Crumpton
crumptoncycles.com
Instagram
"Tradition is a guide, not a jailer" —Justin Robinson
"Mastery before Creativity"—Nicholas Crumpton 2021
-
Re: Crumpton Cycles
Nick, have you ever made anything else in carbon fiber or would you like to? Any personal projects like furniture or something else kinda offbeat?
-
Re: Crumpton Cycles
nick,
i'm having trouble sleeping at night thinking about the box that will arrive at my door in a couple weeks. looking forward to getting one of your bikes
Posting Permissions
- You may not post new threads
- You may not post replies
- You may not post attachments
- You may not edit your posts
-
Forum Rules
Bookmarks