Dava Picks custom bike

[kingbaby]

I was asked to design a bike for a gentleman named Dave Storey (No relation to anyone here), and after meeting he & his wife yesterday, I decided to take on the project. He has Owned, and restored over 200 cars & motos. I was asked to do a modern day replication of his first bike he had in the UK at age 14, a 1933 Coventry Eagle. I then asked if he wouldn't mind if I bought on a couple of folk that I felt would be a good addition to the project, and he loves the whole "Think tank" concept. So he came out to the track today to meet the crew (which is now the size of a Curling team...And I'm good with that at this point). Unfortunately, Karl & Adam had left already, but Scott, Stewart & Ed were still there, so he got to meet 3/4 of the guys I want on board for the project.

Here's a link to his page, & one to the bike we are replicating.

Some notables that use his hardware: Johnny Hiland, Richie Kotzen, Lenny Kravitz, Keith Urban, Guy Koplitz, Myles Kennedy, Tim Gibson, Frankenshred, Chris Cornell,,,Etc...Etc...

http://www.myspace.com/davapicks
http://classic-motorbikes.net/images/gallery/coventry-eagle-250.jpg

[Cloner]

Maybe a 125 Penton engine....you know...the ones with the radially finned head and the big clunky looking side covers?

Like this....http://www.theowencollection.com/images/Motorcycles/Large/72Penton/72PentonCaseRight.gif

That radially finned head, the stamped steel frame, and the girder fork are the distinguishing characteristics of the bike, too me.  Those, and that sexy tapered rectangular underbody exhaust.  I guess Buell wasn't so revolutionary, after all!  Oh....and the fuel tank.  But that's it.  That stuff and the cool half-enclosed fender.

That's actually a pretty frikkin' cool bike!

[Scottish]

cool shit man! Exciting news all over the board!

[Cloner]

I'm just doing a bit of research and needed a place to save a few bookmarks.

For a frame only at the price of 100 Pounds Sterling:  http://www.andybuysbikes.com/MIS27-07-09.html

For lots of pictures of various Coventry Eagles:  http://www.andybuysbikes.com/Archive%20main%20page.htm  look for 147cc and 150cc bikes

The frame pics are particularly telling, and I'm pretty sure I could build one from scratch that's nearly identical.

[Scottish]

I'm just doing a bit of research and needed a place to save a few bookmarks.

For a frame only at the price of 100 Pounds Sterling:  http://www.andybuysbikes.com/MIS27-07-09.html

For lots of pictures of various Coventry Eagles:  http://www.andybuysbikes.com/Archive%20main%20page.htm  look for 147cc and 150cc bikes

The frame pics are particularly telling, and I'm pretty sure I could build one from scratch that's nearly identical.

THe biggest problem I can see with scratch building would be the corners. That frame looks stamped and the welded together. Sure you could make a scratcher but could you get the edges rolled like that?

+ with the exchange rate around $1=1.5 pounds that's only $150.00 Lot of work for one hundred and fifty bucks.

http://www.x-rates.com/d/USD/GBP/graph120.html

[Cloner]

Scottish....My Brother....Oh, Ye of little faith.....Bow Down and worship, and Ye shall be enlightened.

I am the King Engineer (that's what I call the Engineering Manager, anyway...it sounds more worship worthy) in a company who's primary function is cutting, forming, and welding of steel.

The original frame is only about $150, plus shipping, let's say $200, but it's 80 years old, has had plenty of time to degrade, was initially made from what we would today call "inferior materials" (steel has come a long way in 80 years...both in the removal of sulfur and other impurities that result in weaknesses and in alloying to yield greater strength), and even if it's perfect it's made for an engine/suspension/seat combination I don't have and don't intend to use! 

If we start from scratch we can guarantee that the frame is sufficiently strong, perfectly fitted, and aesthetically correct for our project.  I'd probably enclose the sections rather than leaving open "U" shapes throughout, as closed sections are MUCH stronger than "U" sections, and aren't terribly more difficult to fabricate.  I'd also probably mount the engine and other parts via tabs, both to promote strength (holes = fatigue crack initiation points) and to hide the fasteners from sight to leave a "clean" impression. 

The girder fork, too, could be fabricated by the same technique.  Stuart.....looking at the new pictures I'm now sure that the original was sprung, but was not damped.....at least not hydraulically damped.  One way to damp without hydraulics (a shock absorber, that is) is to use drag in the pivot joints as crude dampers.  One could literally tighten the joints to result in the desired ride.  We should strongly consider hydraulics, as the friction method provides very unpredictable damping depending upon joint condition, especially wet/dry variations.

The more I look, a hard tail is probably in order, but we could do a softie if Dave really intends to ride it much or very far.  The hard tail really enhances the appearance of the bike.

If we like the design we should build two and be prepared to build more.  I think there could be a market for them, especially if we develop a four stroke version.  We could even consider developing our own bottom end for a mass produced cylinder/head combo if we really want to get into the thing.  Maybe a 441 cc pushrod single using the forward cylinder and head for an 883 Sportster or a 450 single using the vertical head from a Ducati 900?  I thought of the Sportster because the engine cases for the 883 are small (dry sump, n'est pas?) and would make a neat package as they have a primary similar to the Coventry-Eagle, which we could force the HD parts to mimick.  We'd probably have to make crankcases and a crank, but that's not terribly difficult for a single, either, especially if we use a pre-unit HD transmission, so all we have to do is support a narrow crank and drive a camshaft.  That way we could use the HD kickstarter mechanism and not have to reinvent the wheel.  I mention pre-unit HD because it can be had, unlike pre-unit Triumph or BSA goodies.  We'd want to do our own head cover, but that's child's play.

Thoughts?!?

[Duck-Stew]

Ok, here are my thoughts:

For $200-$250US, buying that frame would be a wise investment for dimensioning purposes.  A very wise investment.  It's likely running friction dampers as you guessed Scott.  I'm also thinking this bike may be a 2-stroke SINGLE cylinder with two exhaust ports as it only has one intake port...

A 4-stroke single cylinder version?!?  Hmmm...  Could be good.  I copied all the Coventry Eagle photos from that site and it appears that the stamping is only in the girder forks...  That could be easily duplicated...

The seat and tank don't look particularly difficult to duplicate.

[DucDog]

An important question to ask the customer is "how closely does he want the new bike to resemble the old?"   

This can range from 1.  "Looks Like" from 30 feet away to     10.  "Identical To" at 1 foot.  The cost goes up greatly as one goes from point 1. to point 10. 

If the answer is "Looks Like" then a Penton engine (Sachs or Puch) or a number of other engines might work.  This approach along with bolt on black painted metal covers that have the old external shape but hide the real more modern transmission would work. 

There have been and still are rotary friction and hydraulic dampers.  It appears from the picture that the lower fork attachment might incorporate a rotary friction damper since the size of that joint is larger.  Older cars used these kinds of dampers as well.

Stampings, weldments and such can make the frame and forks look very close to the original. 

I think the hard part is the engine and transmission (E/T).  Building from an existing but close E/T is very much cheaper than doing one-off stuff, unless the customer is willing to pay for one-off kind of work.   

Which brings us back to the question of what level of work does the customer really want and is willing to pay for?   

[Cloner]

I think we could actually market this project with a modern four stroke.  There are a few Buell Blast engines on ebay in the 5 to 6 hundred dollar range.  That'd be perfect, I think, as long as we're looking for an homage and not a replica!

It's DEFINITELY a 2 stroke, single cylinder, stu.  The two exhaust ports are misleading.

I think it'd be a piece of cake, and with modern horsepower it'd probably be a kick to putt around on.

[Duck-Stew]

I'm actually on a computer now that's larger than the palm of my hand (Iphone...) so here goes some REAL typing:

The Coventry frame is just stamped steel and it's super easy to duplicate.  Getting this 1930 frame shipped here would be a great idea if for no other reasons than dimensioning and some inspiration.  When we're done...we can sell it off to re-coup a few $ as I'm sure there's some collector out there who would pay the same as we did to get ahold of it.

Air-cooled single cylinder 2-stroke engine?!?  Hmmm...  I had thought it was a twin and thusly the Yamaha RD/RZ 2-cylinder engines of the 60's and 70's make an obvious choice.  Single?  Hmmm..  '70s Japanese Dirt-bike maybe?  Maico perhaps?  I'm *not* a dirt-bike guy so this will have to fall to someone else for a knowledgable suggestion of powerplant.

A nice part of this type of frame will be the ability to hide stuff behind those massive frame members.    I like that...

If we're doing an 'homage' bike then a single cylinder 2-smoker (not a typo) would work fine maybe keeping the displacement around 200cc's like the original was.  The duplication of the twin exhaust port could prove difficult, but if it's an homage...then the few people who DO know that it's the wrong motor will likely appreciate the effort put into it.  Also, I think a rigid rear suspension would be just fine for an 'homage' piece and that would keep the build time and the complexity down as well.

If we're building a 'retro-mod' special which he intends to actually RIDE places....  Well then brother...  It's a whole other ball of wax.  If so, then I think a Yamaha RD250 engine would provide adequate 'scoot' and it would solve the twin exhaust port dilemma as well.  We would have to re-inforce the frame some for the add'l power (another point where it would be good to have the original as a bench-mark).  And lastly...I think if we're building a retro-mod (or a true rider however you want to call it...) then I think we need to 'hide' some rear suspension in there somewhere.  Sprung hubs at the MINIMUM!  I'd like to see a faux hard-tail arraingement with a hidden swingarm and a nice rear suspension as well.


If there are to be add'l frames/bikes built on this same theme, idea, front, wave, whatever...  Why not this engine?!!?



Lifan 200cc 5-speed kick or electric start single cylinder making 16hp...  Brand new...  Or we could just source good used engines of Japanese decent.

[Scottish]

This thread has gotten way cool.

[Duck-Stew]

This thread has gotten way cool.

No, no, no.  This thread was way cool at the onset.  It's just now blossoming is all... 

[kingbaby]

It was good talking with you fellas yesterday

I promise to post more, but for now the "old fashion" phone seems to be the ticket, some things take to long to explain in print. I believe I have the answer to those last couple of Q's. I'll buz you again today after classes, & will have talked with Dave again.

Hope everyone has a good morning. 

[Duck-Stew]

After looking at that frame without the assistance of my favorite drink in my hand....

The thought occured to me that we ought to build it out of square tubing and add sheet-metal gussets to duplicate the factory curves of the stamped frame sides.  That way we could gaurantee the integrity of it.  Down side is it would be stiff as hell and likely make a rear suspension a necessity, BUT with a stouter frame it would surely handle the power of an RD engine....

That, and maybe we could drill out the frame tubes for that minimalist old-school racing look!

Thoughts?!?

[Zaster]

Now that sounds like a project I'd like to be part of.
Not being involved in the preliminary discussions I was wondering where we could
find a location to house the project.