Torques Moto’s 1100-powered GSX-R750 Slingshot…
Legend has it, the unique Suzuki GSX-R “7/11” (GSX-R1100 motor shoehorned right into a GSX-R750 body) was featured within the September 1992 problem of Efficiency Bikes. The bike was stated to outperform a brand new Kawasaki ZZ-R1100 for a fraction of the price, and through the years, the undertaking has impressed lots of of shed-builders to construct Gixxer 7/11 machines of their very own.
“The mixture of the monster torque of a GSX-R1100 and the sunshine weight and brief(er) wheelbase of a 750 chassis ends in a motorbike which ‘Has sufficient torque to drag a Brontosaurus out of quicksand’ and ‘Leaps out of your fingers popping out of corners with out even being requested…’” –Outdated Skool Suzuki
Enter our new buddy Diggory “Digs” Rush (@torques_moto), a London-based design engineer and college lecturer who grew up round his previous man’s BSA and Kawasaki café racers and commenced constructing bikes of his personal on the tender age of 13.
Quick ahead to 2023, and he’s simply completed the 1990 GSX-R 7/11 you see right here, dubbed “Choose ‘N’ Gixx” since almost each a part of the bike was acquired in pick-n-go vogue from eBay, Fb Market, the native autojumble, or from members of the oldskoolsuzuki.information discussion board, who had been extremely supportive of the undertaking:
“Lots of very proficient engineers, racers, and turbo nutcases keen to reply my questions on jet sizes, carb rubbers, and normal compatibility.”
Digs envisioned an 80s endurance racer aesthetic with some wild design touches and trendy efficiency components, discovering inspiration in bikes like Haxch Moto’s Slabside and the creations of Sticky’s Pace Store:
“I’ve at all times cherished the look of the endurance racers of the late 80s, however I’ve by no means had a motorbike with respectable brakes and I’ve at all times wished that traditional twin headlight racer look. So I knew I used to be going to do a restomod with the eventual plan of a gasoline injection conversion…”
Digs has discovered a hell of loads since he was 13, and he introduced his full design and engineering experience to the construct. He 3D-scanned components at College School London, utilized software program corresponding to Solidworks and Cinema 4D to construct the bike nearly, ran Finite Component Evaluation (FEA) and movement research, and turned out an arsenal of billet aluminum components on his Twenties IXL line-shaft lathe and small bench-top mill, figuring out of a council storage.
The consequence is likely one of the most hanging customs we had the pleasure of seeing on the current Bike Shed London Present, and it has the efficiency to again it up: 135 hp, 77.5 ft-lb, and a dry weight of 388 kilos. The suspension setup is very adjustable, together with numerous plates to change the rear suspension linkage ratio. Says Digs of the trip:
“Aggressive and unforgiving, however predictable. In the end it’s very adjustable with 150mm trip top adjustment within the rear alone to make it correctly nosey…”
Beneath, we speak to Digs for the total story on this gorgeous Gixxer 7/11, that includes images straight from Bike Shed London 2023.
GSX-R 7/11 Restomod: Builder Interview
• Please inform us a bit about your self, your historical past with bikes, and your workshop.
So I’m a 27-year-old design engineer and college lecturer. Most of my work is digital and I by no means actually see it as soon as it’s out of Solidworks. I’ve at all times been into bikes and grew up round my dad’s café racers, notably a BSA A65 Lightning and a Kawasaki Z650 which he rode again from Berlin.
I began constructing bikes after I was 13, a BSA Bantam D1 and a KX250, each of that are nonetheless unfinished in my attic. The Gixxer is my first completed construct!
I began constructing this bike on the road after I lived in a studio flat in central London. We had an out of doors space the place the washer was; that was the place I used to maintain my swingarm, brake calipers, and what not. After I purchased new bits I used to strap them to my SV650 and trip into UCL, the place I used to be working on the time, and 3D scan them with Creaform scanner.
My workshop now’s a council storage that I run a 25m extension result in from the neighbor’s backyard. I used to be given the keys to the storage by an previous woman who went to hospital and by no means got here again in mid 2022 and the council now not lease them out as they’re due for demolition.
Since having the storage I’ve purchased a Twenties IXL line-shaft lathe and a small bench prime mill and a TIG welder. The lathe and mill had been damaged after I bought them, however I mounted them up they usually work effectively sufficient for me. That’s the place I’ve made all my suspension mounts, wheel spacers, and so on.
• What’s the make, mannequin, and yr of the donor bike?
So there was by no means a donor bike, however I purchased a body off a man on eBay who was build up a restomod 7/11. He had a number of different bits he offered me as effectively: loom and set of bar controls.
• Why was this bike constructed?
Fully a private construct. I had a go on a GSX-R750WP [1993 / Water-Cooled] and cherished it a lot I purchased myself one as a undertaking. However the output shaft thread was broken and the loom was ruined, so the preliminary plan was to swap the swingarm and entrance finish onto an earlier Slingshot body and use the a lot lighter oil-cooled engine. However this by no means occurred as I ended up simply fixing the WP, so the oil-cooler body turned my private undertaking, diving into kinematics and making a motorbike with all of the components I wished with the aim of getting a light-weight Slingshot that I may alter to swimsuit no matter I used to be using: observe, quick roads, or twisty brief circuits.
The WP is the following undertaking; plan is to make one thing a bit much less treasured so I can get higher on observe. It’s taken a backseat whereas this one has been within the works, however now I’m too treasured to need to rag it on observe till I’m a bit higher!
• What was the design idea and what influenced the construct?
So I’ve at all times cherished the look of the endurance racers of the late 80s , however I’ve by no means had a motorbike with respectable brakes and I’ve at all times wished that traditional twin headlight racer look. So I knew I used to be going to do a restomod with the eventual plan of a gasoline injection conversion, as I really like doing one thing sophisticated as soon as however can’t stand balancing carbs.
When it comes to particular bike influences, there have been additionally a number of bikes that I noticed actually made me need to attempt to push the construct to the following stage. The 2 standout bikes had been the Widow Licker by Sticky’s Pace Store, Haxch Moto’s Slabside, however Paul from Ziggy Moto additionally actually impressed me to strive constructing the entire bike nearly, which I did.
I believe that’s the large purpose behind getting the graphics to look proper. I spent so lengthy making an attempt various things at a really low value. I additionally learnt the right way to use Cinema 4D, which is the software program he principally makes use of as a substitute of my day by day Solidworks, Rhino 3D, and so on. It was a problem in itself!
• What customized work was performed to the bike?
So I redesigned all of the suspension mounting factors and machined them up on my mill out of 6082 ally billet; I additionally made up all of the linkage elements. I machined a brand new crush tube for the swingarm, machined 12.4mm off the sprocket provider, machined a brand new brake caliper hanger, machined the R1M calipers, modified the WP mudguard.
New subframe, new tank mounts. Modified prime yoke (quickly to make one other one), SLA printed speedo mount, Daytona Velma 80 15k tach and speedo, 19-row oil cooler, 8AN traces, rear-set mounts for the Gilles VCR rear units off an Aprilia Tuono, rear single race seat/fairing.
Motogadget bullet rear indicators, machined my very own indicators to clamp on the inventory rubbers from a set of low cost bar finish indicators, aftermarket twin tail gentle/brake gentle. SV650 grasp cylinder, Showa BFRC shock off a 2018 GSX-R1000R, designed a brand new set of graphics fitted by Kent Wraps, radial clutch grasp, braided Hel traces, Lucas lithium battery, 750cdi for ignition advance, BST38 carbs, quick-action throttle.
Additionally did a load of FEA [Finite Element Analysis] and movement research, however that’s all only the start of the testing — have to put them into the actual world now and see if my security elements are sufficiently big!
• Does the bike have a nickname?
So it’s known as the Choose N’ Gixx, because it by no means began out as a motorbike; it actually was simply components from autojumbles, eBay, Fb Market, and the oldskoolsuzuki boards. Nothing is absolutely the prime tier half, however they’re all efficiency components chosen for particular causes. May I really feel the distinction between a set of Z04 pads in R1M calipers over M50’s? I doubt it, not at my ability stage, and definitely not anytime quickly.
• Any thought of horsepower, weight, and/or efficiency numbers?
135hp, 105nm, 176kg dry. Nonetheless to seek out the moist weight and drag coefficient.
• Are you able to inform us what it’s wish to trip this bike?
Aggressive and unforgiving, however predictable. In the end it’s very adjustable with 150mm trip top adjustment within the rear alone to make it correctly nosey. Additionally a load of various linkage plates that may be swapped in to alter the ratio — presently it’s setup for 2-2.28, which may be very near a GSX-R1000 K5. Sadly although, I’m actually not succesful sufficient of pushing it wherever close to its limits!
Massive problem in the meanwhile is the exhaust. I’m ready on a set of titanium headers off a K1 GSX-R1000 as my 750 headers are sitting too low and the hyperlink pipe isn’t serving to my floor clearance in any respect. Again after I had the 750 engine in, it may lean over actually properly. However, that can be sorted within the subsequent couple of weeks. Simply bought to get a dent out by shoving them within the freezer.
• Was there something performed throughout this construct that you’re significantly pleased with?
The rear suspension linkage, significantly the adjustable rear shock mount. It’s my first huge undertaking and diving into kinematics and cargo instances of motorbike rear suspension was a fairly steep studying curve. I learn quite a lot of papers, spammed a load of individuals on LinkedIn who kindly helped me fill within the gaps in my understanding.
• Is there anybody you’d wish to thank?
Oh, fingers down the oldskoolsuzuki.information discussion board — quite a lot of very proficient engineers, racers, and turbo nutcases keen to reply my questions on jet sizes, carb rubbers, and normal compatibility.