Does the world have room for another full suspension design?

[PhoxyMomma]

I expect people who have been reading the silly questions I've been asking over the past few months will have guessed I've been working on a new full suspension design. I'm not going to discuss details of the design at this stage because I haven't decided whether to apply for patents (yes, it _is_ different enough to be patentable). My question is, is there room in the market for yet another full suspension design?

I've ditched the more left-field ideas I was playing with in favour of something which is practicably and economically manufacturable; the welding should actually be somewhat less complex than on many current full suspension designs (fewer frame components); so it should not be any more expensive to build than other limited production full suspension frames.

The design is optimised for cross-country, especially very technical cross country; it's not a downhill design. Although it would be possible to deliver it frame only, the front and rear suspension systems are designed together to work together and the bike would not work nearly as well with a conventional fork. The basic geometry is similar to a family of designs which has been very successful, although with a tweak to address a particular failing of that family.

It looks radically different. There's no question of you mistaking this design from any angle for any current design. So from the looks point of view it is marketable. It will also work substantially better in some conditions than current designs, so from the tech point of view it should be marketable. But the components needed to deliver the concept are not cheap so it's probably going to need to retail in the
US$2500-US$3500 range.

At this stage I have a number of options, from least to most risky/rewarding:

* Treat the idea as yet another air-dream and forget about it

* Publish the details on the Internet in the hope someone picks it up and runs with it

* Apply for patents and try to flog the concept to an existing manufacturer

* Get together with some engineering friends locally and start manufacturing

Any advice?

Oh, and, before you ask, no I don't have a prototype yet.

[PhoxyMomma]

Well, Telelever, from what I've seen of it, is effectively an unequal armed girder fork linkage not dissimilar to the Whyte Plus 4 in pushbike technology; the Tesi and RADD systems are technically similar with hub centre steering on a long swing-arm, not dissimilar to a
Citroen 2cv. That would be quite difficult to do on a push bike, both because it would be hard to prevent the swing arm fouling the cranks and because both the hub and the linkage would be very special and expensive to make. You'd also have quite limited steering.

Linked front and rear suspension I've discussed on this group earlier. You can, a la 2CV, cause the rear suspension to extend when the front is compressed. This gives a stable platform over bumps, but if the front compresses under braking and causes the reat to extend then you end up with a terrifyingly unstable platform. The other thing you can do with linked front and rear is to cause the rear suspension to retract under braking.

Consider that when a bicycle brakes heavily the weight vector of the rider swings forward, putting more load on the front suspension and less on the back. So the front tends to dive and the back tends to extend, further shifting the riders centre of gravity forward and aggravating the risk of the rider going over the bars.

With a leading link fork it's pretty much a no brainer to set the suspension up so that the front will actually rise under braking forces. If you now have a 2CV style linkage, then as the front rises so the rear will retract, tending to move rider weight back and thus counteract the over-the-handlebars effect, while still having the stable platform effect of extending the back when the front hits a bump - best of both worlds.

Yes, I would like to do this. It would require hydraulicly coupled hydropneumatic suspension units at both ends of the bike. My design was originally conceived to have this feature (together with monoblades both front and rear and a gearbox in the bottom bracket)
but these are all features I've now abandoned as too complex at least for iteration one.

[PhoxyMomma]

It does have drawbacks inherent in the design (not many) but following the advice given by others I'm not going to discuss them because it would give too much away.

The Klein Mantra has that feature. It's gone out of production now, mainly because

(a) front suspension dive under braking combined with forward weight transfer caused the already steep steering angle to steepen sharply under downhill braking which scared the sh!t out of a lot of people;

(b) the bottom bracket moved quite perceptibly with relation to the seat, which many people found distracting.

Of course all full suspension bikes have fault (a) to a degree but the
Mantra had it particularly badly because its steering angle was already steep and because the suspension pivot is relatively close to the head tube, causing changes in suspension attitude to have an unusually severe effect on the steering angle.

All URT bikes have fault (b) to a degree but the Mantra was the most extreme example so far of a high pivot URT, with the pivot further from the bottom bracket than on any other design I'm familiar with, and thus had it worst.

Having said that, while people who hated the Mantra really hated it, a lot of people really loved it and people whose opinions I respect have described it as the best full-suspension cross country design so far.

Note that the rear suspension on a high pivot URT doesn't actually lock when you stand up - in fact, the suspension travel is still there and the suspension will still work. But the feel of the suspension changes dramatically and many people feel that it has locked. Bob is also usually less than on other suspension designs because of the fixed chain line, meaning that chain tension has no effect on suspension travel.

[PhoxyMomma]

The geometry is capable of long travel (up to about 200mm at both ends) but my assumption is that you will typically want to tune it to deliver a lot less than that.

[PhoxyMomma]

Well, frankly I'm most interested in seeing it built and having one to play with. But that I can probably do myself (and will need to anyway as a prototype if I'm going to do anything with it myself). But I'm also a late-middle-aged software engineer wondering how many years
I've got left in this game and thinking about a career shift, so the idea of setting up a new bike company is somewhat appealing to.

[ElectricJellyfsh]

The market place has room for another full suspension design, however, unless it is wonderful it will make the designer or manufacture no real profits for years. Only the big companies and established names, Trek,
Santa Cruz, Intense, Giant, etc, can bring a new design to market and expect it to sell well the first few years. Most consumers of FS frames want to be assured the pivots and frame members will not wear out and/or break in an un-reasonable amount of time. Also consumers do not want to buy a frame a manufacture that stops producing replacement parts because they go out of business.

Your original post also mentioned the possibility of having to use a proprietary fork design. I think that would be the death blow for your product. Many people I know are very loyal to their brand and would be un-willing to gamble on two new designs at once. Also without years of experience in the design and manufacture of suspension forks and millions of dollars of R & D and reliability testing can any company bring a fork design to market that will do well.

Don't forget to budget in the money needed to sponser racers for a couple of years and the libility insurance you will need when someone rides on of your bikes off of a 12 story building and blames you for their idiocy.

[PhoxyMomma]

Yes. Apart from the frame and fork there are no custom components. The pivots in the frame and fork could use either bushes or bearings, but there's nothing very special about either. The bike uses two identical air suspension units, but although the earlier plans called for quite heavily customised units this is one of the areas I've simplified - Fox Float R units would do.

[ccrider]

You might find it difficult to get a manufacturer to sign such an agreement, if the company does design of their own. It essentially compromises their internal staff's design flexibility going forward. On the other hand, contract manufacturers and custom builders probably deal with this sort of thing on a regular basis.

[cat_on_my_head]

may have said:

There is ample room and plenty of demand for a good one. If it's simply "yet another" and not significantly better in some useful respect (functionality, travel, durability, expense, etc) then the answer becomes "yes, but you've got some stiff competition."

At least you're targeting a market that's large enough to have some potential sales.

That price would put you into the "limited production" range, it's true.

I'd go for the the patent if the funds are available, unless you're more interested in seeing the bike built and marketed than in making money from it.

Possible avenue:

Search for and team with an existing frame maker whose designs are stodgy but whose techniques are adequate. File the preliminary paperwork for the patent (and believe me, when you get to the point of building the prototype. all sorts of things will be discovered that you weren't considering) and then build the prototype. With the first unit in hand and adequately tested, proceed with the patent and publicity.

When searching for a frame maker, be prepared for a lot of them to do the "Oh gods not another Genius With a Revolutionary New Frame Design" reaction. Many have heard and seen too many such pitches in the past.
Others will cheerfully tell you that they'll be thrilled to build whatever you want, at your expense.
If your primary interest is in getting the design built rather than in making money, then publish it after filing the initial patent paperwork.

[PhoxyMomma]

It isn't two new designs, it's one integrated design. Neither bit will work properly in isolation from the other. However, it may be that as you say the market won't buy this.

Having said that, you wouldn't put Ford front suspension on a Porsche;
you wouldn't even put Lotus front suspension on a Porsche. We expect good cars to be built as integrated chassis, with all parts dependent on interactions with all others. Sooner or later bikes are going to be built that way because it's inevitably better. But you're probably right that a new entrant into the market can't make that change of mindset.