What to do with a Monster?

What to do with a Monster?

In October 2015, I was approached by a fellow EAB (elefant adventure bikes) member, Paul G, to look at the ill fated Terra Monstro project. A project which started out in the USA and for whatever reason (bearing in mind litigation) seemed to come to an abrupt end.

I was asked to re-visit the design, highlight the potential engineering issues and design a new, better, ‘green lane’ frame….as a 1 off.

In late November 2015, I had researched the project, put together a general design, with my concerns and points of reference: Ducati V twin engine, Cagiva Elefant Suspension and its easy- neutral geometry, added to the OEM Ducati bodywork but heavily modified frame from a Monster.

That is how it started and that was what lead to the article you are about to follow.

Paul G sourced a Ducati 620ie from 2004 and the basis of an Italian (green lane) mongrel was taking shape.

The Italian word for Mongrel is Bastardo……….hence the title.

Paul, took many photographs of his very tidy 620ie ….these 2 show the 620 monster before the start of the build

Before getting the bike ready for the conversion, you can see “the better the starting condition…. the better the finished product”

And before I said ‘I could do it!’ to Paul G…..I purchased a frame from a monster to test and act as a prototype for the builds

My frame stress calculations dictated a rather unusual result and on double checking the figures just re affirmed the first result.

So much so that that the actual OEM headstock was really only used for a spacer!

2 very large 75mm dia spacer cups were machined from solid and turned off centre (eccentric) to move the headstock axis forward in the OEM headstock.

This enabled the use of the seriously heavy duty bearing tapered bearings in the diameters that the calculations called for.

The new ‘off centre’ bearing cups were pressed into the Ducati frame and welded.

Strengthening gussets and plates were added whilst the frame was held in a jig.

The calculations had dictated a longer by 80mm steering stem and deeper bearing surfaces, over the new extended length …but most importantly was the shear test and the new gusset triangles needed to keep the headstock welded to the frame.

A long bracing strip had to join the old headstock and both the new bearing cups before being machined back in profile after every thing had been welded then cooled.

Each bearing cup had a small M6 holes drilled through …to make headstock bearing replacement easier later in life…although the bearings are very, very heavy duty.

Once the bracing strip had been machined back in profile, a steering lock tube was drilled and welded into place.

This was beginning to turn into a serious piece of alteration.

Next…the side plates…

I had decided that I wanted to design a frame which connected the swinging arm pivot point with the engine and also the frame….similar to the Cagiva Elefant.

We took 3 sections of alloy and mated 1 of them to the engine (via the M10 bolts cast into the engine)…then 1 plate to the swinging arm pivot point and the final plate to the frame and ‘drew ‘ where the all interacted.

This information pattern was then transferred to a CNC planning machine where a drawing with all axis points could be plotted.

This was going to be right…it had to be ..it was not for my use!

Calculations had also called for additional bearings on the swinging arm axis and this when added to the 30mm plates would eliminate any flex and potential cracking

Bearing cups, containing new 27mm wide needle bearings, were pressed onto the new swing arm spindle and mated via 6 off M6 bolts to the side plates

You all have seen cracked engine cases (stress) after an accident and I have witnessed first hand the shearing of a headstock on a front crash!

The whole side plate assembly was then offered up and positioned and tightened accordingly. The spaces between the side plates and the engine will hold the cradle for the Kevlar bash plate that Andy Young has been testing over every boulder in Boulder, Colorado!

As I said the frame was a test bed…sourced from a breaker in ESSEX but the same year to Paul G’s…….here it is with his seat and tank rested in place on the test bike.

The guy in the background??…..he who commissioned the build
…and the one who will ride it…a pensive….PAUL G

If you search the internet and view the original images of the TERRA MONSTRO you will see that they used a spacer above the OEM frame and maintained all other integrity as originally designed by Ducati for the MONSTER. The side plates appeared to be cosmetic and there to hold the foot pegs….there was no addition rigidity added to the OEM frame

The calculations I used, were based on turning motion and leverage….do not know if anyone uses them… but they are used for calculating wind power columns on wind generators.

Somewhere along the line the Bastardo will face a head wind
…so better safe than sorry!

The Bastardo side plates were designed to assist in the strengthening of the new spindle which is made from a tougher (not harder) material and longer

The original 620 Monster footpeg hanger assembly, was rubber mounted and fixed via isolastic bushes to the frame and the engine

Whilst the new plates had a bit more function.

We wanted to make the side plates, a nicer machined option, which made the lines flow better and allowed the fitting of new and additional bearings either side.

The gaps between the engine and the sideplates will hold engine spacers which will also act as location points for the KEVLAR bash plate.

Whilst on the other side the OEM side stand will be lengthened….re profiled to miss any frame work….. braced and fixed between the engine and sideplate.

Likewise the new sideplate to Ducati frame top fixing bolt position will double as one of the rear peg hanger fixing points which can be added when Paul G decides to take the kids out for a spin.

Bearing in mind it was not for my use, I wanted to make the frame changes …strength test it and when happy offer the final conversion to Paul G….it would then be up to him to decide if he wanted to proceed.

James from ESSEX WHEEL & ENGINEERING finalised all the welds and stated that he was happy…with ‘the mechanical structure’

THE OWNER : PAUL G

Paul G bought Paul K’s son Cagiva Elefant E750 and used that for a few years before going the Gas Gas route and green-lane exploring.

He had viewed first hand my Fant 888 build on our way to the Dutch Treffen many years ago (2006…I think) and had kept up to date with my mechanicing-hobbying-squeezing big things into small spaces malarky via this website.

I think he had fancied the notion of getting me to pen an idea and see what would happen.

I have worked with James from ESSEX WHEELS & ENGINEERING for many years and he has built all my wheels…swingarm conversion…quick wheel change systems, stainless spindles…..remote action gear levers….and anything else in my head which had to be turned into metal.

He took my ideas for the BIMOTA DB9- DB11 thing* and machined to pretty exacting standards …..whilst watching me fret over costs and design…on many occasions , it was only when it was finished and fitted to the bike did James actually understand my methods/madness!

This was where Paul G had seen what I had last done to a bike other than a elefant…James does good work…and he will be offering this conversion as a commercial project once everything is done.

THE ACTUAL BUILD……. USING THE PAUL G BIKE

So the strip down begins and Tony the Paints S2R 800 fant is the donor bike along with Paul G Monster 620ie.

Paul’s 620 monster is donating the engine, frame and swing arm along with all electrics, injection system and body work whilst Tony’s bike will be dismantled to get access to the complete Cagiva elefant 900ie front end including 19inch wheel, all foot peg and control items gear lever rear brakes etc.

Over and above this….the elefant 17 inch rear wheel, cush drive/sprocket carrier and disc assembly will be matched to the Monster 620 swing arm.

I even plan to utilise (if I can) the Kevlar copy of the Andy Cadney (the well known mud-slinger) Rogue elefant bash plate

The exhaust headers from the elefant will be modified and hopefully marry up with the DEVIL end can Tony had fitted to his S2R Fant.

So…..ideally…..it will be a true Monster/Elefant collaboration giving the elefant feel to the overall bike rather than the ‘Monster on stilts’ complaints of other modified bikes.

The actual welding of Paul’s bike was done via a jig to hold all the sections together.

The elefant yokes had a smaller stem diameter and not wanting to machine the stem or the yokes….top hats were made to bush out to fit the big taper bearings.

In order to remove the stem with the least stress…an oven was used.

It was at this point we realised the oven turned the yokes gold….
discovering a cure for the Greek debt crisis..
…………..a kebab was bought to celebrate

Above are the actual large/hi load spec taper bearings, top hats and their respective dust covers …machined from aluminium and beneath are a shot of my snazzy boots…fashion slave!

Here is a view of the top bearing cup, their brace sections, the top bearing dust cover, elefant 900ie top yoke and an old set of bars

This time the bottom section…

From a different angle….you can also see the lock stop and adjustment in the threaded boss.

Then there was the new longer stainless steel Suspension.

Tie Bar with adjustable rod ends….we utilised the standard Monster SACHS shock for the build but the owner can re specify any shock and length according to usage and cost limitations.

The swing arm welds and brace section………..the monster swing-arm had its brace fitted and a provision for a rallye prop stand …it is the tube section welded at right angle to the arm length…..similar to the ones fitted to the Azzalins was welded to the swing-arm. A prop fits into this tube section and forms the prop stand.

When the side-stand is down….you tip the bike over (backwards) on the side stand and insert the prop…this makes a tri pod between the two stands and the front wheel…lifting the rear wheel in the air for wheel changes etc….with some strategic placed rocks(!) you can achieve the same result in reverse …..leaving the front in the air!…very ingenious.

This method was first used by Cagiva in the 1988 P-D race and copied every year there after.

The general frame assembly went well and even the standard elefant headers fitted albeit a double exhaust gasket may be needed….but it looked like the monster frame had been made to take this set up!

These shots show the detail of the side needle bearing cups which bolts via 6 M6 bolts to actual side plates adding a bit of rigidity to the overall swing arm pivot point area.

The standard elefant uses a 17mm dia spindle where as the Monster uses 25mm. We could either change all the bearings in the wheel and sprocket carrier.

OR we could bush the brake calliper plate and the rear adjuster….choices. …choices. …in the end we could not source bearings of the correct load specification to allow for the elefant hub reducing to the 25mm spindle…it was mechanically easier to bush and press fit into everything according and keep the standard elefant wheel bearings etc.

Here is the assembly shot of the adjusters in the arm.

First real view as it is assembles form…

From the exhaust area…

And from the rear….anyone would think it was meant to be…

Everything just…. looks correct…..after a bit of exhaust pipe bending to get the line right.

Here you can see the true extent of the bracing…..

And the steering lock stops…….

We measure the lowest point to set ride height……

Dry build finished………ready to be collected by the painter Chris…who will finish the actual build once everything is plated and painted….his standard of work is very very good. That is his monster tank fitted ‘loosely to the frame’ and the seat and end-can have also been ‘just positioned…not fixed’ ..but you can see the work done on the re jigging of the exhaust pipe….the actual sight lines look good.

Ignore the block of wood under the bike….it was there for the the side stand height ……the last thing to be modified and welded….a standard Monster side stand altered to the lean angle the owner wanted…meant that about 55mm insert to the stand length and re welded and fitted….heavier springs and all good to go…….

The bike left the fabrication area of ESSEX WHEELS & ENGINEERING and headed to Kent where Chris of CT Motorcycles (Maidstone) took over and applied the paint and the knowledge to reassemble.

It was his job to source the platers/finishers carry out all the paint and generally complete from the dry build given to him.

This meant that boxes and packages of sparkly stuff arrived!

And the actual build begins

Visually the naked bike just showing the engineering is always the prettiest

The best looking bikes have no wiring or any other details…but you can’t use them.

The original elefant footpegs were treated to a over size peg weld…..

The benefit of paint makes a lot of difference!!

The paintwork, it’s design and execution adds to the overall project

The whole project starts to actually come to life and the finish is superb.

A credit to Chris at CT MOTORCYCLES

A lot has happened since November 2014 when the idea was first muted, over a coffee at Thurrock service station on the M25.

The project called Rana Bastardo (Mongrel Frog…to give it is full name) actually started…which is a unusual……many do not…and now it is finished.

Which in project building …….is a bigger rarity!!

General Idea and money: Paul G (owner)

Frame Design, Stress calculations and responsibility if it snaps ..me!!

Machining and welding: James @ Essex Wheels and Engineering (Chelmsford)

Paint Design and final assembly: Chris @ CT Motorcycles (Maidstone),

* The Bimota DB9-DB11 thing…….take a 2012 and very expensive DB9 cut and re fabricate the alloy sub-frame to make a true 2 seater ….move the styling away from the street fighter design and implement whilst keeping the ‘Bimota look’, their style and engineering excellence and only using BIMOTA DB9 and DB11 parts….a Bimota DB9-11!

Use only OEM carbon fibre body parts…and complete, whilst restyling the new titanium exhaust…footpeg assembly, controls, wider handlebars, ECU upgrade and new rear seat section to take the weight as specified by the factory…….

Google a BIMOTA DB9 (in its original form, complete with its rear wheel hugging light/number plate/indicator assembly) then look at the pictures below, to see true the level of the modifications.

But, in the end… the folk at BIMOTA (Rimini) seemed happy…..as I was.

where there’s is a frog………

By | 2017-07-27T12:57:55+00:00 July 27th, 2017|Latest News|0 Comments

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