Misspending our youth again with a vintage racing Slingshot
In 1985, Suzuki changed the motorcycle world when it introduced the original GSXR750. The bike was like nothing that had come before it, with styling, performance and ergonomics borrowed straight from the GP racing grids of the day. This machine created a brand new segment in motorcycling, the sportbike. Unless you were a motorcyclist back then, you can't imagine how much the game changed when that first GSXR was launched. While 1980's-era cars were barely able to get out of their own way and most motorcycles of the period were sporting spoked wheels under chrome fenders, these new sportbikes were the fastest, best-handling vehicles that money could buy. To top it all off, those early GSXRs and the competitors which quickly followed, were affordable. Anyone with a decent job and a bit of credit could own one.
As we age, it's hard to avoid feeling nostalgia for our lost youth. "The good old days" seem somehow magical in hindsight. Remember you and your boys, wheelieing down the boulevard at night aboard a pack of Ninjas, Viffers, Fizzers and Gixxers? Lounging on your machine in the Burger King parking lot and flirting with the girls like you were the lead singer from Ah Ha? Shutting down Six-Six Bandits and Five-Slows with a mere flick of the wrist? Remember when marriages and mortgages were old people problems, while all you had to work out was how to afforda fresh set of Metzler Comp Ks? When the best purchase of your whole year was spending your tax refund on a pipe and a jet kit, just in time for riding season? Oh, to be young again!
Shot through the heart
The American Historic Motorcycle Racing Organization, (AHRMA) has a class called Next Gen Superbike. Its focus is on recreating the look and feel of professional, production-based Superbike racing in the era of the late 80's and early 90's. The eligibility list for this class includes all the great 750cc V4 and inline-four machines of the day, plus the Ducati 851 and 888. OUCH! Talk about being shot through the heart by the demographic arrow! If you're a motorcyclist in your forties or fifties with racetrack riding in your blood, these are the machines that you started on. Your youth is calling collect. How can you not accept the charges?
Close friends and barn finds
TrackdayMag.com Senior Editor, K3 Chris Onwiler, and Contributor, Rob Oliva, share some great history, virtually all of it involving motorcycle racing. At one time, Rob owned a motorcycle shop and sponsored K3 in CCS club-level competition. Later, Chris built the Red White and Buell project bike for Rob, a machine which never took a green flag without landing on the podium. Later, K3 filled the role of crew chief when Rob went AMA racing as a privateer. Over the years, this pair has covered many a mile together, always behind the clock and short on the dollar, enjoying plenty of great times and suffering through a few major defeats. Any relationship based so exclusively on trial-by-fire is sure to be a close one.
Both Chris and Rob have been interested in the Next Gen Superbike class since it was launched. These days, Oliva is a sales rep for Parts Unlimited. One of the shops he services is Milton Cycle, LLC, located in Spencer, Iowa. This place has a decidedly vintage attitude, primarily because of its decidedly vintage owner, Steve "Wildman" Milton. Steve is a longtime racer himself. These days, he satisfies his competition urges by building vintage racing machines for newcomers to the sport. Rob made the "mistake" of mentioning his interest in Next Gen while at Milton Cycle. Wildman isn't the guy you tell something like that unless you're serious. He was probably spinning his Rolodex before Oliva got out of the parking lot.
In short order, Wildman called Rob back with the news, "Hey, I found your bike. It's a barn find '88 GSXR750 Slingshot! Bring $1200 and a truck next time you stop by." OOPS! Just like that, a vintage racing project was born. The problem was, Oliva already had too many other irons in the fire. The Slingshot went home with Rob and there it sat. New barn, same fate. Then, with the AHRMA races at Road America just three short weeks away, Rob had an idea. He called K3 and said, "Hey, I'll let you race this thing if you can get it running." Clearly, the task of resurrecting a crusty old sportbike and competing aboard it in a racing event, all within a three week window, would be a nearly impossible undertaking. Naturally, K3 accepted the challenge.
Ran when parked
This old Gixxer appeared to be a really decent starting point. It had been raced before, which meant that the machine was already extensively safety wired to the strict standards of the WERA rulebook. The bike featured a battered but serviceable 4-1 racing exhaust, a jet kit, steel braided brake lines and a racing shock. So far, so good. The problem with a twenty eight year old motorcycle though, is that unless somebody else just got done rebuilding it, the bike needs everything. Time is as wearing as mileage, with corrosion and dry rot contributing as much to the difficulty of a rebuild as worn out parts or crash damage. Disassembly and inspection told us a lot about the Suzuki's history. Whoever had built this GSXR for racing in the first place was a real craftsman. We found lots of loving touches in the way this machine had been put together and maintained. That's where the good news ended. As happens to many obsolete racers, this bike had been returned to street trim and sold. The squid who bought it quickly rode the Gixxer into the ground, both figuratively and literally. Cosmetically, evidence of at least two crashes was clear in the bike's scratched and cracked street plastics. The Suzuki's new owner did a bit of touching up with spray cans but didn't bother taking the bodywork off first, so there was overspray on everything. Also, the fork seals and shock reservoir hose had ruptured, either from dry rot or abuse; however, the squid had chosen to keep riding. Consequently, the entire machine was coated with a layer of baked on suspension oil and grit. The brakes were still sporting the racer's safety-wire, indicating to us that the Gixxer's's final owner had managed to ruin the machine in less miles than it takes to use up a set of pads.
Rob and K3 live about eight hours apart. Blackhawk Farms Raceway in Beloit, Illinois, was a convenient meeting point, especially since Rob was already headed there for a CCS race weekend. K3 met him in the paddock at 11:00pm on a Friday night and took possession of the Slingshot. The STT season opener at Autobahn Country Club was just a week away and would be the perfect chance to test the bike. Could it be ready to ride in such a short amount of time? Only one way to find out.
We got home from picking up the bike at 2:00am Saturday morning, took a quick nap and were unloading it from the van by 6:00am. The first order of business was to see if the engine would turn over. We pulled out the spark plugs and removed the timing cover, then stuck a wrench on the end of the crankshaft. The motor moved a bit but not very easily. To facilitate things, we dumped a dollop of 10w fork oil down each plug hole. This helped substantially, allowing us to roll the motor over a few dozen times with relative ease. Satisfied that the engine wasn't seized or rusted stuck, we proceeded to the next step.
If you've got fuel, air and spark, you can make fire. Fuel needs to be stored in a clean container and fed through functional, leak-free carburetors. Our tank was horribly rusty inside so we filled it with four gallons of a product called Metal Rescue, left it to soak and got busy cleaning the Mikuni CV carbs. We were using K&L rebuild kits that Rob had provided but these weren't complete. Off we went to see longtime friend, competitor and sponsor, Eddie Bingham, at his shop, Naperville Motorsports. Eddie specializes in older machines, which proved a huge help to us. Before our visit was over, he'd sourced our needed o-rings and also supplied fork oil and seals, fuel lines and filters, spark plugs and a petcock rebuilding kit. He even had the nearly impossible to find petcock lever that always gets broken on this model of GSXR. It was a restorer's shopping spree for sure.
Once the carbs were rebuilt and installed, we needed to change the oil and filter before trying to start the bike. This proved to be a nightmare. Our machine has a racing exhaust system of unknown origin, which fits the motor like shrink wrap. The only way to get the filter off was to remove the header. It was then that we discovered a smashed primary tube in the exhaust, so off we went to another longtime sponsor, K&S Welding, of Kankakee, Illinois. Owner and master fabricator, Pat Kennedy, cut the damaged section out, re-contoured it with a ball peen hammer and then welded the piece back into place. Amazing. Needless to say, this was an after-hours racer emergency and as usual, Pat came through for us.
While the paint was drying on the header, we pulled and drained the oil cooler. These early GSXR engines from 1985 to 1992 were oil cooled and feature a whopping 4.5 quart capacity. At least a quart of that oil is in the radiator and the only way you're going to get it out of there is to pull the cooler and lines off the bike, tip them over a drain pan and wait for about an hour while the nasty old tar drips out. We had just finished putting it all back together when Eddie called to tell us that he'd remembered how those oil lines for the cooler would always leak if you didn't use Teflon tape on the connections. So back apart everything came. In truth, with a project like this each assembly is going to be taken apart and put back together multiple times. We were just glad to get that good advice prior to crashing in our own oil and it should be noted that this was just one of many times that Bingham has saved our bacon over the years. He's been around Superbike racing since the first GSXR was a new model and remembers all the old tricks, plus all the new ones. We're lucky to have his help and involvement with this project.
Finally, we attempted to fire up the motor for the first time. With the bike rigged to a test fuel bottle, (you're officially "old school" if you own one of these) we hit the starter. Lots of spinning but no combustion. Oh, wait.... Carburetors, not fuel injection. Should we maybe put on the choke? That done, the bike fired immediately! Within seconds, it was smoking so badly that we couldn't see a thing. In a panic, we quickly shut the motor down and opened all the shop doors. This was bad. We'd never seen a bike smoke so much. It was as if somebody had literally poured oil into the combustion cha.... Oh, yeah, right. That was us. Doh! We fired the bike back up, let it run for about ten minutes and were pleased to see that the smoking cured itself as that 10w fork oil we'd dumped in earlier burned out of the motor and exhaust system. Fortunately, none of the neighbors called the fire department.
Now that we had a runner, it was time to take care of sanitizing. This Slingshot was the filthiest machine we've ever attempted to rebuild. No matter what we wanted to work on, it had to be cleaned first. We went through 20 cans of carb cleaner, several tooth brushes and ten rolls of blue paper towels during this first week of the project. The stench of grease, stale gasoline and cleaning chemicals was thick in our shop and on our clothes. We took out the reeking shop garbage every night, as we feared that the accelerant-soaked trash might spontaneously combust while we were away and end this project with a funeral pyre.
When you're working all day to earn a living, working all night on your motorcycle and not bothering to sleep for days on end, you need something to keep you going. We chose 1980's Hair Metal, played loud. Hey, period correct music can really help get you in the proper frame of mind for a project like this! At one point, it occurred to us to check the 1988 Billboard list to see which songs were popular when our bike was new. Def Leppard released their Hysteria album in the fall of 1987 and it was all over the airwaves in the spring and summer of 88. That album had a ton of hits, including Women, Rocket, Animal, Love Bites, Pour Some Sugar On Me, Hysteria and.... (are you ready for this?) Armageddon It.
This song was released as a single and made it to number three on the American charts. Wow. The karma was so right that we just had to laugh. Now our bike had a name. They say that you should never bring a knife to a gunfight. Well, we were preparing to go vintage racing aboard the AHRMAgeddon Slingshot.
For a shock, Rob had provided a Sachs triple-clicker that was the stock takeoff from his 2014 BMW S1000RR racebike. It was in brand new condition, having been replaced immediately with an Ohlins damper during the BMW's build. This shock is a direct bolt-in for the oil-cooled Gixxers and is a massive upgrade from anything which was available when these bikes were new. The forks were straight and rebuildable but had some really funky, progressively wound springs in them that had to be compressed a whopping 60mm just to get them onto the damping rods. We cleaned all the parts inside and out, installed new seals and oil, then put them back on the bike. When we bounced the front end after reassembly, the forks seemed to bottom out way too soon. Fortunately, we knew we'd be seeing yet another of our sponsors, Ken Hall, of Superbike Suspension, once we got to Autobahn. We'd have him look things over before we tried to ride the Gixxer.
Believe it or not, brakes were the easy part. So often, the calipers and master cylinders of old bikes become corroded lumps of junk but in our bike's case, the ownership history of a racer followed by a squid worked in our favor. The racer had maintained his brakes in superb working order, then the squid had unwittingly coated them with a thick film of protective and preserving suspension oil! All we needed to do was scrub the calipers down, change the fluid and slip in new brake pads. In the days when Rob and K3 were chasing the AMA Privateer dream, their closest ally was a guy named Chris Jensen. Jensen has worked as a sales representative or racer support provider for many top level moto-companies and he always seems to be at the track. Whenever the guys got in a major jam, Jensen would show up at the most opportune moment and lend just enough help to save the day. It was perfectly fitting that we should involve him in this latest K3/Rob collaboration. Currently, Jensen represents SBS brake pads. He informed us that the same Nissan calipers mounted to our Slingshot were also used on the Yamaha TZ250, a bike that is still popularly raced around the globe. Because of this, the very latest SBS Dual Carbon racing pad compound is available to fit our old Suzuki. Not only do these pads stop like mad, they also offer the benefit of extremely low drag when the brakes are not applied. With them installed, the old Suzuki pushes around the paddock more like a bicycle than a 28 year old motorbike. Since these first generation GSXRs don't have a lot of horsepower by modern standards, it's good that we won't have to waste any on dragging brake pads.
Wheels and tires
The chain and gears were in acceptable shape for testing purposes once we'd given them a thorough cleaning. This left tires as the final unresolved issue. Our long association with Sportbike Track Time and Sportbike Tire Service have made us lovers of Michelin's racing slicks. We knew that we could ride this old bike for all that she was worth if we could put such excellent modern rubber between her and the track. It wasn't going to happen without a struggle. The 1988 Suzuki GSXR750 Slingshot used 17-inch rims, just like modern bikes. Up front, a modern 120-sized tire would fit the stock wheel. The rear rim was only 4.5 inches wide though, not big enough for the 180 and larger tires used today. By scouring the archives at the Gixxer.com forum, we were able to find out that people have swapped in a 1993 GSXR600 rear wheel, which is 5.5 inches wide and will hold any race tire we'd want to use. We got a rim from EBay and proceeded to try and fit it up. Well, those long ago forum users who'd said that this was going to be easy were wrong. The wheel swap did eventually work out; however, we wound up having to make a spacer on the K&S Welding lathe, machine the seal mounting lip off the gear carrier, replace the carrier bearing with one that had an internal seal and space the front sprocket 7mm further outboard so that the chain would clear the tire. K3's dad saved the day here, making a parts run for the needed bearing right at closing time Friday and delivering it to the gatehouse of Autobahn Country Club, in Joliet, Illinois.
The last modification required to fit the larger wheel into the Slingshot was to remake the locating arm for the rear brake caliper so that it would clear the 190-series slick that we were planning to jam into the swingarm. This was a last-second deal, occurring during the time when we should have been loading up and leaving for the track. As we have done so many times in the past, we headed back to K&S Welding, for yet another after hours racer emergency. To be honest, without Pat Kennedy and his trusty metal glue gun, we'd probably be building and driving Soap Box Derby racers instead of riding motorcycles.
Seven days, one hundred hours.
At 11:00 Friday night, almost one week to the minute since we'd picked up the GSXR from Rob, we arrived at Autobahn. A hundred hours of wrenching had gone into this machine in just seven days. Factor in the need to also work a 40 hour week at the day job and you can begin to understand what a monumental undertaking the project had been. The Slingshot wasn't ready to ride yet but it was close. At this point, we still needed to install the SBS brake pads that Chris Jensen was bringing to Autobahn, mount the new carrier bearing that K3's dad had supplied, rebuild the petcock with a kit that Eddie Bingham was delivering to the track and have Superbike Ken look over the suspension. Fortunately, this was Memorial Day weekend and the Sportbike Track Time event would be three days long, giving us time to finish the bike there at the track. While still a long way from done, our '88 Gixxer Slingshot was at least together enough to test. Would this old dog hunt? It was time to find out.
To be continued....