Showing posts with label mitas. Show all posts
Showing posts with label mitas. Show all posts

16 Dec 2013

Super Motor Co - Dirty Donkey at Monza

Super Motor Co finished their new custom the Dirty Donkey some weeks ago.
After taking the Dirty Donkey to Eicma this year Dimitri tried to ride the bike
on the closed Monzo track. I asked Dimitri for some exclusive pictures and a
write up about the build.


"About the shoot:

The nearest place to be able to take the bike a bit off road after the
Eicma show was near the Monza circuit. So up to Monza. As a stranger 

it was difficult to find out where the back roads were and where I could 
give the bike a spin. I drove up a foot path called Via Vedano, took a left 
and passed under a viaduct and ended up inside the old Monza oval track. 
Totally illegal but a truly beautiful spot. I've had never seen a proper 
banked track. It is so steep, it nearly impossible to climb up by foot. 
Must have been great to have lived in the 30's and to have raced an open 
wheeled race car at speeds over 300 km/h. The donkey is pretty tame 
compared to that. But fun nevertheless. The track and surroundings are 
used nowadays by joggers, horsy types and other leisurely people. 
They looked at us like pariah's when we disturbed their peace with the 
noisy donkey.

About the bike:

This is the story of the Dirty Donkey. Yes It does sound like the title of
an obscure 70's porn movie, but it is nothing like that. It is not that I
am uncomfortable with hairy sex flicks. But this is a bike meant to be
happy in the dirt. Nothing more... nothing less. Dirt Quake here we
come...or we thought so...

After the launch and the success of the Salt Shaker last year. We even came
8th in the biannual Bike Exif list of 2012. We decided to do another one,
with a cub frame as a basis. Being a fan of dirt bikes and especially the
one's from the early days, the decision was made to have a go at one.
Inspiration ranged from an array of vintage mx-ers, desert racers and
dirt trackers: Cz's, Maico's, Husky's, BSA's and last but not least
Aermacchi's. And in particular the Harley/Aermacchi Sprint's used in 60's
flat track racing. With the horizontal single as the common denominator.

Since the Salt Shaker was such a bitch to start and to ride we've kept the
engine stock. The only way to ride it was full throttle. Which I do not
mind but doing the DGR with it was a nightmare. For the bike and for
myself. It just did not like the slow speeds and over heated. It cut out a
dozen of times and took on average 5 minutes to start again, meaning I've
been kick starting it for over a 60 minutes in total. That was no fun. So
no high compression pistons and no flowed heads this time.


Late February I started by cutting one of our own frames up ( no it is not
a Honda frame is is a Super Motor Company frame), and asked Jaap to work
his
magic and weld in a cut up c50 rear fender. Easier said than done because
it was cut and welded on again at least 6-7 times before we got it right.
Since it needed a fuel tank the search was on to find one that fitted
between the headstock and the seat. I ended up buying a Honda Camino tank
that did fit the space but was not really the look I was after. After a lot
of eyeballing we decided to flip the tank 180 vertically, which included
lots of cutting and shutting, drilling and welding. But it did result in
the desired effect.

 
Check pictures of the bike in progress on previous Bubble Visor post in February. 
The deal was to do a co-op with OO racing. They would supply
the engine and we would do the rest. But in some weird way the whole co-op
vaporized. Suddenly OO Racing's priority lay in some odd turbo charged 30
bhp plus Monkey bike ( nice one for toddlers with an acid addiction) and
they backed out. I rate them very highly for their engine work but not for
their word. 
Inherently the Dirty Donkey was fridged. I also
have a business to run so I've had to let it go and that was it (for the
moment). I really wanted to finish it for Dirt Quake but that was not going
to happen. In the end I raced my own daily driver and came fifth in the
finals of the inappropriate road bike class. With a few more pony's, or
donkey's, between my legs I could have done better. Next year...

Fast forward to September. I finally got an engine and started the project
with a fresh mind and soul. Most of the parts were already in so, it was
just a matter of sanding and priming. Well not really. I had the seat base
done and already upholstered in a magnolia leather but did not really like
it. So made another one, slightly shorter and had my grand mother do it in
a silky smooth desert beige suede. It did create a gap between the seat and
tank but it also gave it a bit of that 60's desert racer feel. Which I
like. Without dissonance one can not challenge perfection. Much better...
Wiring up all the electricity inside the handlebars was also a nightmare,
took me over a day to make it work. People probably have come up with this
idea before and even the bigger motorcycle brands but now I understand
because it's just too labour intense to justify the cost. I really wanted
to do a semi road legal bike this time with some indicators and all other
necessities. Driving the salt shaker on the road was a game of hide and
seek with the police. It was like risking an arrest every time. All alarm
bells were going off because of the extreme noise, lack of indicators etc
etc....the stupid stuff a road legal bike really needs. And since I don't
have a clean sheet (understatement) with the law/police I can not afford
many more offenses. It was stressful to ride so to speak.


I did avoid lots of stress by having the exhaust fabricated before
painting. Nevertheless when the bike was on it's legs the silent block I
used to attach the pipe to the frame melted. I tried all kinds of silent
blocks but none were resistant to the heat generated by the exhaust. I
thought I found one appropriate, but when I gave the bike a go at the old
Monza oval track ( check the short and shaky video

again the rubber looked like a tuna melt sandwich. As being a fan of these
kind of toast's I was not very upbeat about the fried black mini pancake
the silent block turned into. Found a solution in the end with a more
synthetic rubber bushing and skipped the idea of the silent block all
together.


The bike was only on show for 24 hours in Milan during EICMA at Officine
Mermaid and generated lot of interest. Happily, because you never know if
it's going to be thumps up or down.


Main specs of the Dirty Donkey

Engine: YX 140cc SOHC (stock), approx. 15 bhp on the rear wheel.
Carburetor: Uma 28 mm flat slide
Tank: Custom SMC, Honda Camino, cut and shut, flipped 180 etc... to much to mention.
Side covers: Custom SMC in fiberglass.
Frame: Custom SMC, modified by Jaap Volkers
Rear suspension: Racing boy
Front suspension: 680 mm RSU YX forks
Headlight: Rinder, modified (dented to fit between the forks as tight as possible)
Headlight stay: Stainless, Just van der Loos
Taillight: Beta
Rear forks: Custom SMC
Exhaust: Stainless custom SMC , Shipping tools
Foot rests: Stainless custom SMC, Shipping tools
Gear shift lever: Stainless custom SMC, Shipping tools
Brake lever: Stainless custom SMC, Shipping tools
Rims: 1.60 front and 1.85 rear
Tires: Mitas, front and rear 3.00-17
Switches: Custom SMC
Indicators: Fiat
Controls: Vintage Tommaselli, levers and throttle
Handlebar: Aluminium custom SMC, gift (no origin known)
Seat base: Custom SMC
Seat upholstery: My own 89 year old grand mother

Again many thanks go to Jaap Volkers for putting up with me, his physical
assistance and last but not least his moral support and
Lidewij Merckx for the photography. 
 * The bike is for sale. But with a clause. The bike must attend Dirt Quake
and Wheels and Waves next year. Or we will deliver it to you afterwards.
And it comes with EU registration documents. Contact and info at
supermotorcompany.com

The bike is on show and can be tried at one of our main dealers in Amsterdam at
ScooterSpot"

Thanks a lot Dimitri, great pics, cool build and nice story :)













6 Nov 2013

Dirty Donkey update

Super Motor Co almost finished their new custom the Dirty Donkey. Last Sunday Dimitri invited me to look at his latest creation. In March I posted about the Dirty Donkey for the first time but as you can see a lot has changed since then.

I was there when the engine was fired up for the first time. :) We first tried to bump start the engine but something was wrong with the flat slide carb. We found the problem, decided to borrow the kickstarter from Salt Shaker and it came to live with a wild roar. It is loud I an tell you, very load. Check the small video here
It's a mix between a vintage scrambler and trial bike and it's powered by a 140cc engine. This is the second custom coming from Super Motor Company and it share's a lot of design cues from the Salt Shaker. You can see the Dirty Donkey on Eicma later this week.

Dimitri:
"It wasn't all plain sailing when Lenny came to visit me. A plastic cap
inside the carb was mounted upside down. That's why it would not start and
pissed fuel everywhere. On the floor but also inside the exhaust. We've
had to tilt the bike 180 like a rampant horse, or should we say donkey!
And half a litre of fuel poured out.

But the most serious problem was a melted silent block that attaches the
exhaust to the frame. I've used silent blocks before but never a regular
one. The enormous heat generated by the exhaust melted the rubber like a
chewing gum substance. But mounting the exhaust directly to the frame with
a bolt and rubber bushing was no option either. It would peel the paint
off in seconds. On Monday morning I started calling around looking for a
ceramic coated m8 bolt and the lot to stop the heat entering the silent
block. But no success. I could not get one in time. I finally found an
insulated silent block today with a heat resistant gasket inside... thank
god.

On Thursday morning I am off to Milan in the company Beemer touring with
the Donkey in the back. I've had no time to test anything so wish me luck.
The engine runs fine but does not get on full song. Really have to fiddle
with the carb and the jetting. Probably have to go a bit leaner.

let you know about the progress and get back to you with final specs once
the bike is finished and tested..."


Thanks Dimitri and good luck!









See the firts run here