Bill Wilkin's Ducati Monster 900 Project

One of those enthusiasts is Bill Wilkin, who took a stock 2000 model Monster 900 and turned it into what he calls "Il Mostro de Enduro". How did he do it? Read on and find out, as Bill tells the story.

Inspiration for this bike should really be credited to Blaine Dehmlow of Overland Motorcycles in the USA, who took Monster 690s and converted them to 'Terra Mostro' enduro bikes. I had different ideas on the whole Terra Mostro formula, so decided to build my own version. I started out with a garden variety, fuel injected 2000 model Monster 900. It had been crashed, but was listed as a repairable write off. The damage was limited to the usual - damaged fuel tank, bent bars and broken levers. The engine, gearbox, etc. was in very good condition, so that side of it didn't need repair. The engine was in stock spec, apart from the carbon cans it came with, so I left it as is - power was not going to be an issue!
The Monster's frame didn't need replacing or major modification as it is very strong in the right places. Word of advice - don't use an SS frame! The headstem didn't need to be modified or moved, however the ignition lock mount did need to be carefully ground out to provide more steering lock. The only frame mod I did was to cut out the crossmember from under the seat which supports the suspension bell crank for the rear shock. I moved this crossmember forward to just behind the rear cylinder head and used it for the top shock mount. I also added some flat bars to the rear half of the frame for extra strength, as well as a mounting point for bolting up pannier frames, etc. A further two flat bar tabs below the front engine mounts were added to mount the bashplate.

For the suspension, I fitted 50mm Marzocchi Magnum conventional forks with custom made triple clamps to the front. These forks were rebuilt and modified by Paul Rooney to reduce travel to 250mm. On the Terra Mostro bike, they use Honda XR650 forks, which fit into the standard Ducati triple tree, but I prefer conventional forks over the USD type for greater reliability in the bush. One issue to be mindful of is that there's a clearance problem with that top clamp. Road bikes generally have a small "lock to lock" distance. The only three solutions are to either (in the Terra Mostro bike) fit a two inch spacer under the top clamp and lift it up to clear the ignition switch mount; leave the clamp at the standard height (what I did) and modify the switch mount so that it doesn't foul it; or remove the switch mount all together. The problem with removing it altogether is that you no longer have an ignition switch / steering lock or a place to mount a pin for a steering damper. I used a YZ Yamaha front wheel fitted with a 330mm motard disc and a Honda CBR Blackbird front caliper adapted to fit. Once the front assembly was fitted up, I suspended the frame from the roof, strapped the front suspension down to allow for what a standard load would be (suspension sag plus rider weight), then tilted the frame until I had the right rake. I would recommend a rake of 28 degrees. Once this was done it allowed me to make the measurements for the rear shock. I prefer the PDS type shock mounting as it does away with all those troublesome linkages. As stated earlier, I made a new top shock mount just behind the rear head. I then modified the swing arm by extending it a further 100mm and welded in a new shock mount. The rear shock is an Ohlins unit, custom made by Paul Rooney to fit my requirements.

The most important and difficult step in the conversion was the side plates. I had these cut from 10mm 6160 for maximum strength. They fit in place of the original peg mounts and are mounted solidly to the frame. They provide extra strength by solidly tying the frame to the engine in a third place. The standard Ducati swingarm pivot fits only to the engine cases, so I fitted bearings to the inner sides of the plates and made up an extra long swingarm pivot to go into these bearings, that way the engine cases and swingarm have further support, preventing any twisting. The side plates also provide a place to mount the footpegs in a lower, enduro-style position, as well as providing a place to fit the rear master cylinder, side stand, exhaust hangers and rear bash plate mounts. I will be making up a few sets of these plates in the future. If you want some, let me know and I'll do a few more. The more that are made, the cheaper it'll be for everyone!

So how does it ride? Brilliantly! Well it rides just like a big old Cadillac on the dirt with no real bad manners. I fitted an Ohlins steering damper which quietened it down even more. The characteristics of the Ducati motor mean that it has ample engine braking for getting down steep hills, etc. and plenty of grunt for the flat open bits. I did try a flat drag race with a KTM super enduro and kept up easily; I'd say that while the KTM has more power, it also has more weight (I reckon the Duc's at least 20kg lighter) and extra torque.

It was an interesting project, that's for sure, and I learnt a few things along the way. But if I was to do it all over again, I'd go for a smaller capacity bike. To be honest, the Monster 900 has too much power and too much weight. The 600 should be perfect for this sort of conversion, giving less weight over the front wheel, but still with quite healthy power, plus the benefit of better fuel consumption. I'd also forget about the single shock rear and go for twins. Twin rear shocks would have made it so much easier to engineer!

I'd like to thank Paul Rooney and Perry Gilsenan for their help and great patience with this project, especially explaining how suspension geometry works! Paul does a lot of engine, frame and suspension modification work for off-road and adventure riders (works some major magic on GS BMWs), and really knows his stuff. He has a small workshop at Rileys Hill, near Lismore, and can be contacted on (02) 6682 8557. The Monster I created was sold on www.justbikes.com.au, but I'm still producing those custom side plates for anyone who's inspired to create a Ducati off-roader similar to mine. If you're interested, call me on (02) 6836 1608 or 0417 694 822 for more details.

One of the pics shown here was taken during the inaugural 'Scrapheap Adventure Ride', which Perry organised this past Easter to help raise funds for Down Syndrome NSW. It's a great test of your bike building skills, as you have to start with a road-registerable bike bought for less than $1000 and do whatever it takes to get it registered and rideable. Because you then have to ride your creation to a specific destination (Cameron's Corner in 2011), it's a great fun ride. And because it's in support of Down Syndrome NSW (entrants are encouraged to get sponsors for the ride), it's a great cause as well. I'm building up a Yamaha IT490 for the 2011 ride and would love to see a lot more custom creations from JUST BIKES readers heading to Cameron's Corner. Visit the Scrapheap Adventure website - www.scrapheapadventureride.com.au - for all the info, and come join us in 2011!

Special thanks to Graham Rich for some of the images used in this article.

Bill Wilkin