Marx Garage
My Ducati 748 album
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Braking late for the apex of a tight corner, heeled over with the knee grazing the tarmac,
and accelerating hard before the next corner. The rider and machine are like an athletic ballet dancer, dancing to the tune
of a growling desmodromic symphony as the engine revs hard to the redline. On a Ducati, the rider merges with the motorcycle
to become one, and the sensual experience is unequalled. (Ian Falloon). |
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Engine: 748cc, liquid cooled, 90degree V twin. Bore/stroke: 88mm x 61.5mm Compression:11.5 Fuel system: Weber-Marelli fuel injection, single
injector per clinder. Transmission: 6 speed, chain final drive. Frame: Steel trellis. Suspension: Front: 43mm Showa inverted fork, 120mm stroke. Oil 8wt, 480cc in each
leg. Std settings: Comp 12 clicks, rebound 10 clicks & preload 3rd notch from top. Rear: Showa rising rate mono-shock. 71 mm travel. Std settings: Comp
1 turn out, Rebound 1 turn out. Brakes: Front; 2 x 320mm disc, 4-piston caliper. Rear; 220mm disc, 2 piston caliper. Tyres: Front; Pirelli Dragon EVO MTR21 120/60. Rear;
Pirelli Dragon EVO MTR22 180/55. Wheelbase: 1410mm. Rake/trail: 23-24 deg/ 91-97mm (adjustable steering
angle). Wet weight: 207.5kgs Weight bias: Front 47% ,Rear 53% Seat height: 790mm Fuel Capacity: 17litres, Res 4 litres. Range 266.9kms
(average) until reserve. Reserve range 62.8kms max. Major service: 10,000kms. Claimed hp: 98 (72 kW) @ 11,000rpm (std). Sprocket ratio/ final drive: 14/38. Drive chain: 520, 94 links. Max speed: 240km/hr (std). Avg Consumption: 15.7 kms per litre (measured). Personal Suspension settings: Front settings: Pre load: 5th notch from top. Compression: 11 clicks out. Rebound: 11 clicks out Rear settings: Preload: 40mm sag from static, with rider weighing 76kgs. Compression: 1 turn out Rebound: 1 turn out. 10,000kms Major Service: (Australian Dollars, as at 10/05/02) Oil Filter: $14.92 Fuel filter: $37.88 D9EVX Spark Plugs:$14.45(ea) x2. Oil Shell Ultra: $52.50 Gaskets: $16.70 Air filter elements: $20.66 (ea) x2. Cam Belts: $86.09 (ea) x2. (every 2 yrs or 20,000kms) Labour: $420.00
Sprocket prices 06/03/02: Final drive kit (front 14, rear 38, Regina chain) $495.00. Tsubaki Alpha Gold Chain (O-ring 520)$195.00. (Labour ) $90.00.
Horror stories Ducati 748/916-998. There are quite a few stories out there within motorcycle community circulating about Ducati reliability &
the problems encountered by their owners. I dont want to paint a grim picture of owning a Ducati as there are just as many
horror stories on other makes as well, but I thought it would be better to cover all perspectives to owning a Ducati
748. Below is a few of the worst stories I have heard in relation to Ducati 748/916 problems. I cant really say how common
they are, but there have been one that I have personally come across on my 748. Voltage regulator problem. Earlier Ducati 748/916 had problems with the voltage regulator
failing causing loss in the charging system, leaving the bike to run off its battery in a "total-loss" system. This can be
diagnosed by running a voltmeter across the battery terminals & revving the bike to 4000rpm, you should get 13-14volts,
anything below 12volts indicates that the system isnt charging & a faulty voltage regulator may be the culprit. In Australia,
a replacement unit for the earlier 748/916 (pre-1999) will involve a slight rewiring due to the current, more reliable, japanise
unit having different connectors. In Aust you'll be looking at about $570.00 to fix the problem. Recall on rear swingarm. There had been a recall on earlier Ducati 748/916/996 rear
swingarms. The problem stemmed from owners/servicers overtightening the pinch bolts at the rear of the swingarm when doing
chain adjustments (the rear axel runs off-centre through "drum" which can be rotated to adjust the distance from the counter-shaft
sprocket). Over-tightening can cause stress fractures around the pinch-bolt holes on the swingarm, or these can fatigue during
use. Later models are OK & I understand that the recall was purely a cautionary move. Cam Belts. This would generally apply to any motorcycle running cam belts, but for
some reason Ducati 748/916 etc the cam belts have to be monitored closely. Replace every 20,000kms (moderate/spirited road
use) or 2 years (increase frequency if heavy road & track work is common). The risk of them failing would obiliterate
the engine. There seems to be 2 types of cam belts available, those running white labels on the belt (run on most factory
originals) & the red labels which are recommended (which are some kevlar compound in them I think). If in doubt replace
them anyway. Cost is about $90AUD (each approx). Desmo valve system. This is all hear-say (I have not witnessed cases of this), but some people
out there have told me that the Desmo valve system actually runs close to its threshold limits at peak rpm on 748 & 998R
etc. These engines produce a healthy delivery of power right up through the rev range, but the sudden (some feel severe) cut-in
of the rev limiter may have been a measure taken to avoid excessive stresses at higher revs. After hearing this I have tried
to limit "over-rev" with my 748 (which isnt easy on a race track with ya mates breathing down your back, or from someone used
to in-line 4s). Also there have been instances of the "chrome facing" on the rockers to wear excessively (this is the plating
on the contact surface of the rocker to the camshaft), although Ducati 916 1995 maybe OK. This has been an issue that Ducati
has acknowledged as problems with the chrome plating on some models (1996-1998 ?). My 1997 748 has done 18,000kms (July 2002)
& I will see what my servicer says when they do the 20,000kms service. Accessories I would consider: Slip-ons (End cans). From new, if you can afford to by a Ducati 748 or 916/998 then you can afford to buy a set on aftermarket slip-ons. One of the most wonderful things about the Ducati Twins that owners & non-owners can appreciate is the sound. This is only enhanced with a good set of Slip-ons. So please, let others enjoy the sound of your baby as much as you do & fit a set of Termi's or equivilent. Of course you'll also have to consider getting the fuel injection system (Black box) Chipped to compensate for the freer flowing exhaust to avoid backfire/flat spots/etc, but settings vary with countries that run different fuels, so see your local Ducati dealer for advise. Rear hugger. The amount of stones kicked up by the rear wheel that hammers the rear shock is amazing! Especially when the tyres heat up, everything not tied down sticks to them & is flung up under the rear guard (A hits the rear shock etc). A rear hugger would definitely help here. Radiator screen.The Ducatis radiator is large, broad & is impacted by just about every stone & bug it comes across. A lot gets kicked up by the front wheel as well, & after a while the assortment of bent rad-fins increases. After-market rad screens available locally here in Aust & no doubt overseas as well is a good investment.
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The stand shown in these photos was something I threw together on a rainy
day up at my Parents place. It's amazing what you can do with some spare time & cyclone fence pipe.
Why a Ducati? Why a 748? I have been riding motorbikes for a while before the desire came over me to buy the Ducati 748. When the original 916 came out in 1994 (Australia), like a lot of people, I loved the look, the sound & later the track-bred performance raved by the biking community of this bike. Of course at this time the 916 was prohibitively expensive for me & I had resolved myself to admire it from afar as unattainable. Through the mid 90s my interest in off-road at that time gave way to the blacktop when I purchased a Kawasaki Zephyr 750 in 1997. By then Ducati released the 748 alongside their 916 & I liked the idea of a smaller, revvier twin in such a beautiful package, although still expensive in Australia the 748 was retailing for much less than the 916 in what was essentially a similar bike. My decision to go for the Ducati 748 came from the exposure to sportier/faster motorbikes & riders (when I went from my Zephyr 750 to a new Honda CBR600 in 1999), and the fact that my riding was becoming more the weekend scratch in the hills or track days than anything else. In my time riding road bikes through the 90s I was getting quite a bit of feedback of what owning a Ducati Superbike (748/9XX) would involve from owners themselves. This was beyond the exclusivity & uniqueness that the brand bestowed & went more into the increase cost in parts/servicing & problems of reliability & maintenance. I was under no illusion that owning & riding a Ducati 748 would not be just a simple issue of more $$ = more power/handling etc. Even so the price of 2nd hand 748 were coming down & I had an bloke interested in my Honda CBR600, which made the change a attainable & desirable thing by 2001. Why a 748? Isnt more cc better? My recent past riding road bikes had highlighted to me that power wasnt everything, riding a 600 in-line 4 or a 748 twin wasnt a disadvantage when up against the litre bikes in just about all the applications I was going to put the 748 to. I found that in many cases the smaller cc engine actually made the bike easier to ride faster, where the engine wasnt a factor that could catch you out too much but was there to provide the kind of power-to-the-ground that got show going. Sure its not as lazy as just turning the throttle for that power kick, but the smaller engine is so much more rewarding when you have it wired. I have now owned my 1997 748 Bi-Posto for 2 years & clocked over 29,000kms since I bought it. In this time with drawing from my own personal experiences all I can say is that all the stereo-types & generalisations made about owning an Italian motorbike like the Ducati 748 are essentially correct. Youll find yourself revelling in a wholly new exhilaration of riding motorcycles with the Ducati, but the effort, expense & drama will be there to test your metal.
As you can tell by the sign behind the Duke, this must be a fun piece of
bitumen. Because it's so close to Melbourne it gets little crowded here on Sunday Afternoons, but it's still a good scratch.
The Reefton Spur from Reefton to Lake Mountain/Marysville is pretty tight and one of the few public roads I get my knee down
on. On the Duke it's mostly in & out of 2nd & 3rd gear but the Honda CBR600 involved alittle more gearlever input,
but still loads of fun. It was even a ball on the Kawasaki Zephyr 750 & KLX650.
Reflections on my Ducati 748 Bi-Posto Strada 1997: Good points: Styling. Theres no denying that the 748 (916/998) is one beautiful motorcycle.
Its inspired design has still meant that in 2002, 8 years after first being released, it still looks up-to-date & turns
heads. Even when this design does date its the sort of bike that will remain as a modern classic. Underseat
pipes, single-sided swingarm & compact (narrow), stylish design has set a benchmark in motorcycle architecture. Engine. Handling. Bad points: Steering lock. Lack of turning circle. Without spinning up the rear
wheel to square off U-turns you would be left with going from white line to white line on a single lane (either way) carriageway. Riding position. Fairing doesnt offer a whole lot of coverage. Looking front-on to the 748 the overall bodywork
is so small that it looks more like a 250 than a 748/916. Side by side any of its equivalents the Ducati looks tiny. When
on board at speed its difficult to get out of the buffeting behind the screen, not surprisingly just about all race-prepped
Ducati 748/998 now run higher screens. My 748 Bi-Posto has its fairing held in place by Quick-release Dzud fasterners (10x
for both lower fairings to expose the engine). Headlight spread is OK at night, the Ducati 748/916 set-up with the duel headlights is that
the left is low beam & the right is high beam. They work independent of each other, one comes on the other goes off. Current
748/998 run 2x park lamps where previously (like my 1997 748) run only one park lamp in the Low-beam light Cost. Appointments.
The story of the 748 Quattrovalvole Ducati had been given the budget to take on the Japanese by the company's new owners the Castiglioni's.
With help from Cosworth, Inginiere Bordi updated the 4V Desmodromic treatise he had prepared as a student at Bologna University
and set to work. The valves were quite small and, to get the Desmodromic mechanism in between the valves, the valve angle
was not as flat as Cosworth would have liked (an included angle of 40 degrees rather than a sub 30-degree number that could
have been achieved with valve springs). Ducati wanted to stick with their preferred Desmo system and decided the sacrifice
was worth it. The bore and stroke were the same numbers as the F1 engine; 88mm bore and 61.5 mm stroke. During the road bikes development stronger crankcases were designed and the engine grew with the 851
(92 x 64 mm) being the first engine released. The valves were unchanged from the prototype and were still designed to fit
over an 88mm bore however. As the road bike range got bigger the engines grew in size, first to 888, (with 94mm pistons) then
916cc, by taking the stroke up to 66 mm. Apart from increased valve sizes, the head remained the same. Once the 916 range was established Ducati wanted a smaller sports bike; not as one would expect, just
to compete in another capacity category, but also to allow a different experience to the owners, this was to be an engine
that thrived on revs, buzzy and radical compared to the 916's tractor like torque. The bike comes with slightly lighter flywheels
and a closer ratio gearbox (the same one found in the 996SPS actually). The market dictated that it should be sold for less
than a 916, and although it is difficult to find any difference in many engine components of both models I still have not
worked out why it is any cheaper to build a 748 than a 916 (or a 996 for that matter) as apart from bore and stroke they are
identical (same size valves are in the 748 as the 916). This leaves us in the superb position of having many 748's out on
the street that can be best looked upon as shrunken 916's, seriously overbuilt in terms of strength. The 748 range has historically had several different models. The basic is the 748 Biposto, then there
was the 748 SP and SPS. Since 2000 the 748R replaced the SPS . The same Biposto engine also comes in the 748 Mono (in the
US) and the economy 748S and 748 models. The engine has a wonderful free revving quality and makes superb noises both from
under the tank and through the pipes because of the revs. If there is a problem it is that the redline is very near to the long term reliability limit for the
desmo system operating the valves. Most street owners do not get any problems, but by the time you have the redline of 11500
rpm being hit really regularly (you will only do this by going flat out on a motorway or blitzing round racetrack) things
will need servicing more than every 10,000kms to keep them reliable. There is no internal difference between a 748 and a 916 apart from the bits that are affected by the bore and stroke changes.
In a perfect world you would want to keep the revvy, effervescent, nature most owners wanted when they bought the 748, you
would also want to give it a bit more grunt out of the corners and allow the usual speeds with a little less stress on the
valve gear. If you could do this without any compromise in reliability you would have the best bike Ducati never built.
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