Moto Guzzi conversion Doc Jensen Racer No. 59

Moto Guzzi conversion Doc Jensen Racer No. 59

The love for more

Jens "Doc jensen" For the year of the many Moto Guzzi anniversaries, Koch is presenting his most extensive conversion to date: the Moto Guzzi Doc Jensen Racer No. 59.

The mother of all two-cylinder Guzzis, the M.oto Guzzi V7, is celebrating its 50th birthday this year, and the sports icon Le Mans is turning 40. On the one hand, that is hard to believe, on the other hand, it forces us to look at their historical merits. They are enormous, says Jens Koch, and that should be proven powerfully. Jens can (and must) think that way, because he lives (from) Guzzi. He can speak on the topic for days, his nickname has become the company name: Doc Jensen. Fully shot since he bought his first Le Mans in 1987, completely insane since he started trading motorcycles and parts in 1998, and fully professional since he opened his master workshop northeast of Hamburg in 2013. He does care and maintenance – "no, honestly" – with pleasure and posh, but he gets into talking about his conversions. How everyone was happy about his V2 scrambler on the occasion of the Hamburg Motorbike Days in 2015.

Moto Guzzi conversion Doc Jensen Racer No. 59

The love for more

Design comes from Sylvain Berneron

Jens Koch is not vain, but he likes to make high demands. So in mid-2015 he gathered his courage and asked Sylvain Berneron to design a racer. A really modern one, and specifications for some parts, always self-produced, he also expressed. The master agreed, towards the end of the summer two files came back with sketched racers, one a little bit more radical, the other somehow more radical. One should choose, wrote Berneron, and make final wishes, then he would make the final drawing. Customizing in the age of internet and globalization. The Koch couple – Martina is the congenial doctor’s assistant in the shop – had a hard choice, and that’s why the sketches found their way onto the website and at events. Should customers and friends decide. In the middle of this decision-making phase, however, a first interested party came forward and wanted a mixture. All right then.

A five-axis machine milled the models for the tank and seat from a fairly large piece of beech. While aluminum and GRP specialists went to work, Jens looked for the machine parts. The modified frame of the 1970s T3 tourer takes on the engine of a Le Mans 2. Well done is that. With slightly larger valves, slightly increased compression, a camshaft designed in-house, a lighter single-plate clutch instead of a double-plate clutch, double ignition, oh, it doesn’t stop at all, but there is one more thing that should be knocked out: the camshaft drive takes on elegant spur gears instead of the series chain, like Conceived by Vienna’s tuner legend Peter Horvath. What for? Because of the technical aesthetics, and perhaps also because no chain tensioner can steal performance. The engine says thank you and delivers 82 HP and 83 Nm, by the way, although the doctor was unfaithful to one of his basic recipes: he normally prescribes an airbox, “because funnels are always swirling somewhere. But that doesn’t fit a cafe racer. "

The snorkeling of the carburetor remains clearly audible

Said motorcycle species is known to have originated in England, around 1960, when the boys ran races for the blocks and ran displays in front of the cafe with their twins dressed up. Handcrafted care and self-loving details were an essential part of it, all in strict proletarian tradition: the best worker builds and operates the most important devices. Finished. If you don’t understand this, you should make designer furniture, not a cafe racer. But anyone who, like Jens childishly, can look forward to the sparkling, conical relief bores of the locking screw of the adjuster of the clutch Bowden cable is allowed to do so. Here the beautiful rises almost unnoticed above the pure purpose. This is exactly how cafe racers work. And when everything from this screw to the flawless paintwork, the clean electrics, the artful and leather-covered bench to the tail light perfectly fitted into the hump has been duly admired, then only one wish remains: Let go, the cart.

It sounds powerful from the exhaust system devised by Doc. Not overpowering. The snorkeling of the carburettors remains clearly audible, and the V-Twin reacts wonderfully spontaneously to throttles. Are there miracles? Sometimes it depends on the point of view. Anyone who has brought 100 series Guzzis on their toes, for whom this engine comes at least from another world. The whole load does not tip over to the right when driving off. This is due to the significantly lower masses. That’s why the thing turns up so silky. We have Guzzi scale, yes, yes, yes, but still: that the olle two-valve engine can be so spontaneous and civilized! The revised transmission has undergone a similar development in Jensen’s basement workshop, and – just like the single-disc clutch – can be operated easily and precisely, in short: everything is pretty creamy.

Test round leads back to the Hamburg fish hall

The tight dress by Sylvain Berneron and the targeted technical equipment by Doc Jensen naturally result in an intoxicatingly low weight. Fortunately, narrow tires retain the resulting advantages, and that is why the racer turns nimbly and never looks wobbly or unstable. As expected, the Nissin four-piston pliers grip with confidence and are easy to dose. The decidedly sporty seating arrangement could be made much more comfortable thanks to adjustable notches and handlebar halves, a concession to the future owner are the rather hard-tuned spring elements. Something else?

No, the small test round leads back to the Hamburg fish hall. In the past it was completely proletarian, today it is a hot spot for after-work prosecco. The Guzzi roars past well-filled terraces, guys slide their sunglasses into their gel hair, ladies put their glasses down. One would like to be able to think now, “yes, there you look, eh? Everything self-built. ”But one on prescription from the doc is damn good too.

Conversion information Doc Jensen Cafe Racer No. 59

Fred siemer

The fork revised by Doc Jensen comes from a Honda CBR 900

technology

For the Moto Guzzi V7 Sport from 1971, chief engineer Lino Tonti designed a flatter and stiffer frame that all V2 Guzzi later adopted. The one used here and shortened in the rear area comes from a T3, an undisguised all-rounder. The engine was supplied by a Le Mans II, it was completely rebuilt and extensively modified. The transmission came again from a T3. The fork, also redesigned by Doc Jensen, comes from a Honda CBR 900.

Technical specifications

engine: Two-cylinder V-four-stroke engine, bore x stroke: 88 x 78 mm, displacement 942 cm³, two valves each (inlet 44, outlet 37 mm), DJG (Doc Jensen Guzzi) camshaft, driven by DJG steel spur gears , crankshaft facilitated and Finely balanced, double ignition, DellOrto carburetor, Ø 36 mm, DJG exhaust, power: 82 hp at 7500 rpm, 83 Nm at 6350 rpm.

drive: lighter DJG single-disc dry clutch, five-speed gearbox, cardan drive.

landing gear: Double loop frame made of tubular steel, modified Showa fork, Ø 45 mm, fully adjustable, Wilbers stereo suspension struts with adjustable rebound, double disc brake at the front with Nissin four-piston fixed caliper brake calipers at the front, single-disc brake with Brembo two-piston brake caliper at the rear, wire-spoke wheels with Akront flat shoulder rims, front 2.50 x 18 ", rear 3.5 x 18", tires front 110/80 x 18, rear 140/70 x 18, weight without petrol, with all oils: 181 kg.

Contact

  • Doc Jensen Guzzi, Auf der Horst 53, 21493 Elmenhorst
  • Telephone 0 41 56/82 08 82
  • www.doc-jensen.de

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