Loading ...Morewood Proto DH Bike
Wednesday, March 19th, 2008
So we sought out some more information from Morewood awhile back on their latest prototype. You’ve no doubt seen some shot in spy photo’s from various races around South Africa over the last twelve months (Yes, it has been out and about for that long more or less). Details inside.
Morewood has tried quite hard to keep the project under wraps for some time as it is a completely different direction for us, one that we were not certain about the future of, and we did not want the word out before the decisions were made. Now, with what will hope will be close to the production version of the frame finalized and with the announcement of our involvement with Team Pyrenees Morewood, and the pictures of Fabien Pedemenaud’s race bike finding themselves on press releases, forums and race reports all over the web it is time to blow the lid open on this beauty that we have been drooling over at Morewood for a little while…
First off, it’s a Morewood designed bike. It is a radical step in the Morewood design and has been tweaked and refined by Mr Morewood himself. Additionally it has been built from the ground up in our shiny new factory in Pietermaritzburg, South Africa piece by piece.
Entrance To the Factory (photo: Gary Perkin)
The idea:
We wanted to make a thoroughbred race machine, and with the Izimu as the starting point the foundation was set and the plan was as follows: take everything that contributed towards the Izimu being a great race bike: solid chassis, hassle free pivot interface, race tweaked geometry, and a lightweight tube-set. The next step was to work on what could be improved on the Izimu: lowering the centre of gravity, reducing the unsprung mass, tweaking the shock rate, and lowering the leverage ratio.
Careful Planning: Building On the Izimu (photo: Gary Perkin)
The thinking:
Throwing a few ideas around about how to achieve and improve on what was already a great race bike, we came up with a few rather radical ideas. After a long process of elimination, much head scratching, and some pretty extensive initial prototyping we came up with V1.0. We retained a single pivot chassis, opted for a dropped chainstay swingarm and added a linkage to actuate the shock, thus allowing us to lower the location of the shock on the frame, reduce the unsprung mass by using a lighter swingarm and both tweak the shock rate and lower the leverage ratio. DING DING DING! Do we have a winner? Not so easy!
Preliminary Morewood Protoypes In the Corner (photo: Gary Perkin)
The process:
Coming up with idea’s is sometimes the simplest part of the design process. It took many weeks and months of drawing, machining, welding, riding, tweaking, re-drawing, swearing, throwing, re-welding and riding before we came up with what we were happy with, and even then there was still huge room for improvement. This is all part of the way in which we make every new Morewood frame; Mr Morewood needs to be fully satisfied with a project before it gets the stamp of approval [big Morewood sticker down the side] but judging by the smile that was plastered on his face last weekend after riding his prototype frame for the last time before jetting off to Taipei for Taipei Show… I’d say he’s pretty satisfied with this frame.
Morewood Prototype with BOS Shock and BOS Cartridge (photo: Gary Perkin)
The frame:
It is essentially a single pivot frame: the rear wheel moves in a fixed arc about a fixed pivot point. What makes this different is that there is a link that connects the rear shock to the swingarm, this is where all the magic happens. What this has allowed us to do is the following:
1.) Lower the leverage ratio:
- Lowering the ratio between wheel movement to shock movement makes for a more controlled suspension action; essentially more oil is flowing through the shock so any damping adjustments you make are more pronounced and effective. This also reduced the stresses in the frame and swingarm -due to shock action- allowing you to lower the reinforcing needed where the shock is mounted. Thirdly it reduces the required spring weight needed to achieve the optimal sag point, lightening the bike and once again reducing stresses.
2.) Lowering the centre of gravity:
- By bringing the largest concentrated piece of mass [rear shock] on the frame as low as possible the entire centre of gravity of the frame is shifted lower, contributing for a more nimble feeling bike; the bike moves around more easily through tight turns and is more stable in a straight line with the lowered mass concentration.
Low Center of Gravity (photo: Gary Perkin)
3.) Reduction of unsprung mass:
- With the new swingarm configuration that the link allowed for it was also possible to reduce the mass of the swingarm itself, this equated to reduced unsprung mass where it counts the most: at the rear wheel. The lighter swingarm holds lower inertia and hence is more inclined to be displaced and provides for a more active and more supple rear end.
4.) Tweaked shock rate:
- Finally, and most importantly the addition of a linkage allowed us to tweak the shock rate to perfectly suit the characteristics and handling of the frame and its suspension. Working closely with our test riders, these shock rates have been finely tuned to provide the rider with a rear suspension that is completely active over the smallest high frequency inputs, while still remaining stable on bigger, deeper suspension movements. With a fairly linear initial to rising mid to final spring rate the frame sits well in its travel, without being too harsh in the initial part or sitting too far in its stroke under static weight.
Linkage Driven While Maintaining Simplicity (photo: Gary Perkin)
Chassis basics:
- 1.5” Headtube [low stack height, stronger interface, larger range of set-up options]
- 10.5” x 3.5” Shock [the big sucker that gives you the 2.3: 1 leverage ratio, do the math]
- 12 x 150mm Rear Hub Spacing [industry standard]
- 83mm bottom bracket shell width
- Izimu style Ali derailleur hanger and axle [light, strong, proven]
In House Machined BB and ISCG-05 Guide Tabs (photo: Gary Perkin)
- Two piece CNC machined BB and pivot casing with machined ISCG05 mounting tabs [stiff, stiff, stiff]
- SPI 2 Pivot system [our SPI made better in 2008, connects the swingarm to the front triangle in stiff style]
- Sealed bearing shock link pivots [hassle free, low maintenance set-up]
- CNC machined, anodized shock links [light, stiff and durable]
CNC Machined & Ano Shock Links All Made In House (photo: Gary Perkin)
The result:
What we have achieved in this prototype is a frame that has the same handling characteristics that Morewood owners will have come to love; the bike is light, lively, and responsive to rider input, the rear end is incredibly stiff, and the chassis is low maintenance. On top of that we have added increased traction through superior suspension action, tweaked shock rate and lowered leverage ratio, better handling due to tweaked geometry, lowered centre of gravity and reduced unsprung mass. All of this providing for a frame which we believe to be among the best on the World Cup circuit.
Fabien Testing In the Cascades (photo: Gary Perkin)
Fabien Pedemanaud’s 08 Morewood (photo: Gary Perkin)
http://www.morewoodbikes.com
Some Questions & Answers
Will it see production?
Morewood: Like excited, expecting parents we are already picking out and arguing over names… that must mean something?
Is it Rootbeer?
Morewood: No, the colour is actually a clear powder coat. The colour tint comes from pre powder coat treatment. Its truly unique, and no frame comes out the same. Its hotter than Rootbeer and slicker than Cream Soda!
Is Bos as good as the hype?
Morewood: YES we believe it is! Do I need to expand on this? After a little over a week of testing with Fabien Pedemenaud on our local tracks I can confirm, yes, BELIEVE THE HYPE!
Previous Coverage
March 19th, 2008 at 3:27 pm
I think they look cleaner than the commencal but regarding Lowering the centre of gravity the commencal wins
March 19th, 2008 at 5:10 pm
When I saw this a while ago it straight away reminded me of a Commencal.
I definitely like it better than other Morewoods, but it is hardly ground breaking design.
With that being said, I would choose it over a Commencal…but definitely not in that colour, sorry Morewood but you really should have chosen some better colours!
Cheers,
Ken
March 19th, 2008 at 6:25 pm
much more professional looking than the commencal and it’s handmade with pride. i like the straight top tube more than the CAD drawing though. looks to be a WC machine!
March 19th, 2008 at 7:15 pm
I’d like to see a mag like DIRT run a back to back test between this, the new Commencal and Turner DHR.
And why not chuck in the new Rocky for a 4 way comparison!!
March 19th, 2008 at 10:52 pm
Like a Trek session 10, but the Trek looks better.
March 19th, 2008 at 11:00 pm
That would be a neat comparison test to do between those bikes.
As far as the Trek looking better, well that’s a matter of opinion
March 19th, 2008 at 11:40 pm
I third that comparision…excactly the comparison i want
March 20th, 2008 at 8:13 am
looks like a cross between the commencal and the turner looks sick tho
March 21st, 2008 at 10:46 pm
Nice bike, really like the 2.3 leverage ratio. i think the top tube from CAD would flow more with the lines of the swingarm.
i fourth the comparison also
March 22nd, 2008 at 7:14 pm
Very much the commencal vibe..head to head this the comm, turner dhr and ok, yes thr rocky in a dirt showdown and i am all ears and wallet
March 23rd, 2008 at 1:01 am
Thats a thrustlink system!.
Good news: A fully rising rate.
Bad news: Be ready to spend money on those main bearings,no matter how big they are,they carry too much load.
March 26th, 2008 at 4:59 am
looks like its going to be a mud trap by the shock,