KZ1000: First Ride and Further Inspection.

Beautiful... With about 45 minutes into the carbs, the bikes running and idling fine. It's time for a ride, but after a quick inspection of all the major systems. Brakes? Check. Lights? Check. Tire Pressure? Add some air, Check... and so on down the list. Good... Everything looks fine. We're ready to ride. It's 10pm already and the Kerker is not a neighbor's best friend so it's fortunate that we don't have many.

Snapping the throttle open, the bike revs up pretty well and doesn't hesitate or stumble, with just a little wisp of black smoke coming from the exhaust. Is it black or is it blue? It's dark out and the only "fresh" gas I had kicking around was 2-stroke pre-mix... Maybe it's set up right? "This thing should be a monster," I think to myself. High compression, big bore, high-lift, free flowing old school muscle... Okay, GO already!

The very first thing I notice after throwing a leg of her and maneuvering out of the driveway was how heavy it is. Compared to my 1978 KZ650B, the 1000 is a tank. Actually, it's more comparable to it's GL1200 stable mate than the 650 in the mass department. At somewhere close to 600lbs full of fuel, it's definitely not light, but the long-ish Suzuki GS swing arm exaggerates it's heft in the driveway for sure.

We're riding now... The front tire has taken a set from sitting so long to it's dancing around a bit, but it's more annoying than unsettling. Being a bit unsure about what type of monster I have here I didn't want to unleash the beast on cold tires so I put a few miles on before going WFO. Cruising down the road at 55mph the engine is turning just over 3000rpm and it has decent but not overwhelming power when rolling on the throttle. Unfortunately, this bike, like it's smaller brother KZ650, is a premium fuel only bike. If I open it up too much at low RPM with 87 octane it pings and knocks like a Jamaican metal drum convention during an earthquake. I sure hope premium fuel solves that so I don't have to retard the timing... roll-on power is what this bike is supposed to be all about. Because the pinging is so prevalent, I can't really get a good feel for the KZ's real-world road power. I guess I'll just have to see how it spins out tonight...

The anticipation is killing me: GO WFO! The 7750 redline comes and goes pretty rapidly in 1st gear. Then again in second, and in third. Brakes... Legal again... Okay, yeah, it's faster than the KZ650 and KZ750. But I'm not blown away by it. In fact, to be honest, I'm disappointed with how flat it feels up top. It pulls well, it goes good, but not like I feel it should considering all the work that's been done to it. After a few backroad runs, my best seat of the pants guess would be about 85-90 rear wheel horsepower. Whoopee. Isn't a stocker supposed to be in the 80s? Definitely nothing like a stock Suzuki Bandit 1200 (115-ish rwhp) or even a Buell S1W Lightning(94rwhp). I'm not 100% convinced that I won't have more fun on the nimble little 650 even without the grunt. Is there something wrong with this bike?

Maybe... Did you catch what's up with it? Although I haven't tested my theory yet, there are a few hints in this post and the last one. It has to do with the PO's friend switching over the carbs. And it's not that the pilot jets are too lean... (cue Jeopardy theme)

Kawasaki KZ1000: The next big thing.

It seems that I've become a Kawasaki guy as of late... A quick look into the garage shows 5 Kaws, 1 Honda, 2 Yamahas, 1 Suzuki, and 2 Triumphs. I've always have been partial to the first generation of Honda SOHC fours as being overall great motorcycles, Kawasaki's four banger offerings of the mid to late 70's have been growing on me like fungus. This particular bike, a 1980 KZ1000 LTD is my latest craigslist find and a gem (to me) at that! I'd consider it to be a mild "period-custom" with a lot of pretty neat hop-up mods that were likely done in the early 80's. Some of the goodies include: 1054cc big bore kit, Corbin Gunfight and Lady seat, Dyna Electronic ignition and coils, Suzuki GS aluminum swingarm, alloy wheels laced up to the stock hubs, Progressive rear shocks, K&N superbike bars, a halogen headlight conversion, welded and gusseted frame, and many chrome doo-dads on the engine and footpegs, etc. NICE... While I'll normally prefer restoring a bike back to stock, period mods that don't drastically change the character of the bike (improvements...) aren't all that objectionable to me. As my first experience with a big Kawasaki four cylinder, I wasn't quite sure what to expect from it. The engine was rated at around 84hp stock (I assume this to be crankshaft hp) according to a few different websites I saw.

When picking up the bike, the previous owner said that the carbs would need to be cleaned in order to get the old girl up and running. I peered into the fuel tank to check it's condition and the gas smelled as if it were as old as the bike itself so I expected the fuel bowls to be covered in a think green slime. That was not the case. PO had his "shop," a trusted friend, recently put a new set of carbs on the bike as the old units, according to this friend, were badly worn out so they would not idle or run correctly at low speed. Of course, the shop didn't return the 29mm smoothbore Mikunis after fitting the "new" used set of stock 26mm carbs on the bike (which he charged $300 for). Can you say red flag? I think the PO got taken for a ride and his carbs stolen... But I can only speculate. Anyhow, the "friend" did put a 117.5 main jet (vs. 102 stock) to compensate for the individual pod air filters (darn it...), big bore kit, Kerker exhaust, and high lift cams that were installed. But no changes were made to the pilot jets. We'll see how well that works. I replaced the needle valves, blew the carbs out, and refitted them to the bike. The low speed screws were set at 3 turns out. A few strokes at the kicker with fresh fuel in the bowls brought the old girl roaring to life.

Next: Further Inspection and First Ride.

Air intakes and performance exhaust systems.

So the big question in my mind was how the 1982 Kawasaki KZ 750 LTD would perform with the individual pod filters. It was the "hot set-up" "back in the day" to have an individual K&N air filter or velocity stacks fixed directly to the carburetors in order to offer the least restriction and maximize flow and power. Well, maybe that was true back in the 50's and 60's, but that's because the engineering behind those earlier machines was no where near the level that even bikes of the 70's and 80's had. 

Most people know that an exhaust system can greatly affect how a motorcycle performs. That's why when you open up the catalog of any big parts house (Dennis Kirk for example) you'll see pages and pages of aftermarket/high performance exhaust systems for just about any bike out there.  Of course some people want a different exhaust for their bike for aesthetic reasons or because they buy into the old mantra of "loud pipes save lives". (This is a subject best left for another day...) But the industry has traditionally been focused on increasing performance over the stock systems. 

Exhaust tuning is a very complex science that uses many different principals to help evacuate the spent gases from the cylinders of the engine and keep fresh unspent air/fuel mixture in. On single cylinder engines (or engines where each cylinder has a completely seperate header and muffler system) header pipe diameter and total length are two of the largest variables. Remember that the air moving through the engine does not do so in a constant pressure, steady state way. As the exhaust valve opens, the gasses are still burning and highly pressurized as they begin to move out of the cylinder and into the exhaust port and system. There are two distinct energy waves or "pulses" moving into the exhaust at this point: The exhaust gases themselves have kinetic energy moving into the pipe, and the sound wave. The oversimplified version is that the length, shape, and diameter of the exhaust can be designed so that these pulses (and their negative "reflections" sent back to towards the engine when the pulse reaches the end of the exhaust system) can be used to draw more exhaust out of the cylinder when the exhaust valve first opens and "stuff" the fresh air/fuel mixture back into the engine when the intake valve begins to open (especially critical as valve "overlap" increases with longer duration cam timing). When you add in the additional variables of multiple pulses from multiple cylinders in 2-1, 4-1, and 4-2-1 exhausts, it becomes an extroadinarily complex task to maximize power  (I'll go into more detail at a later date in another post).  Also, since the speed of the "pulse" of exhaust gases varies with engine RPM, the exhaust system will be most effective at a certain RPM and less effective at all others.  By manipulating length, diameter, etc., a tuner can design a system to work at a desired RPM.

I thought you were talking about Pod air-filters?

Yeah, yeah... I know... Stick with me though. A well designed air intake system works in a similar way as a well tuned exhaust.  The suction from the engine created by the intake valve opening is essentially a "negative" version of the pulse seen at the exhaust side. The intake tract length is one variable that can be manipulated in order create a "stuffing" effect (literally creating a positive pressure of air into the cylinder).  These energy pulses created by the opening and closing of the intake valves cause a starting and stopping of the flow of air into the engine. This vibration behaves in the same manner as a sound wave which is why the volume of the air intake system and airbox plays an important role in creating the "stuffing" effect.  Think of it in terms of a musical instrument... An acoustic guitar has a hollow ressonance chamber to help amplify the vibrations (sound)  from the strings. The resulting higher "volume" in the case of a motorcycle engine is how large the "stuffing" effect is at the intake of the motor. As with the exhaust system, the volume of the intake system and the length of the intake tract affect the  RPM where the intake system performs optimally.

So that means we can design the exhaust and the intake to work best at peak RPM and we'll have a killer machine right?

Well, with the good comes the bad... These systems will have an RPM range where they work best, but the flip side, is that there is also an RPM range where they will do exactly the opposite of what we want them to do. Remember, we're dealing with waves here... they have peaks and they have troughs. When the peaks line up with eachother, they resonate and amplify their effect, which is what happens at their optimal RPM: In our example, the exhaust is "pulling" it's hardest when the intake valve first opens or the intake system is "pushing" it's hardest when the intake valve first opens. When a peak lines up with a trough, they energy wave will end up cancelling each other out: The exhaust and intake systems are function in essentially atmosphereic pressure. When a trough lines up with a trough, the bad effects are amplified: the exhaust is "pushing" the gases back into the cylinder when the valve first opens and the intake is "pulling" the air out of the cylider when the valve first opens.  There will be an engine RPM where the worst case scenario occurs and power output will drop off dramatically. Of course there are countless ways to combat the severity of the problem, including staggering the optimal RPM range of the intake and exhaust systems, but it still will exist in some form(dynamic intake and exhaust tuning is a recent engineering accomplishment). 

To be continued...

KZ750 LTD: Polishing the chrome.

After bringing the old girl home, it was more apparent that we had our work cut out for us. While it was definitely a solid running bike, the devil truly is in the details.  I don't think the KZ had been stored outside for sustained periods of time, but it was obvious that she had seen some weather at some point during it's 27 year life. The usual rust on the nuts and bolts, the shock springs, a few spots on the frame, etc., were doing their part to detract from the overall impression. 

Please, if you're reading this and getting ready to start a restoration or detail of your own old bike, DO NOT use steel wool on the chrome parts. Yes, many people love doing it because it quickly removes the orange discoloration, but it scratches the chrome and makes for an ugly, albeit shinier part. I can't tell you how many times I've spoken with people on the phone following up on a lead to have them proudly tell me how they cleaned all the rust up "for me" with a Brillo pad and it's looks "really nice".  It makes me want to cry... There is no short cut that I've found to bringing back chrome. Use a non-abrasive chrome polish and patience. The stuff I use is Turtle Wax brand and is around $3 a bottle and the local auto parts store. Hazy chrome that doesn't have a lot of pitting usually is easily cleaned up with an application of the polish with a jeans rag (I'll cut small sections out of an old pair of jeans. This makes for rags with very little lint and are durable enough for heavy duty rubbing on rough edges.) For areas that are heavily rusted and pitted, I'll use the same polish but with a Scotch-Brite pad designed for non-stick teflon cookware. These pads are made from a type of plastic and while offer some scrubbing power, they are designed to be soft enough not to harm teflon coatings and also don't damage old chrome parts. In extreme cases, where the chrome almost destroyed anyway, I'll use a copper Brillo-type scrubbing pad with a liberal application of the Turtle Wax chrome polish to remove the rust while leaving what plating is still there in tact. 

Whenever chrome pieces are polished/scrubbed to remove rust, there will be areas where the steel underneath is now exposed to the elements and will rust again in time. It's critical then to use a good quality wax on the pieces to help protect them from the weather. Unfortunately, the only way to have a like-new piece is to actually re-plate the part. Polishing and rust removal only makes the parts look as good as they can. I've heard of people clear-coating the chrome pieces after removing the rust, but personally I think this band-aid look s lowsy.  In my opinion, it's better to just keep up with the wax and don't store your newly beautified jewel outside (not that you would anyway). 

1982 Kawasaki KZ 750 LTD

I recently picked up a pretty good example of a 1982 Kawasaki KZ 750 LTD. It was all stock except for the individual pod air-filters that one of the previous owners put on it. I'm not a fan of the pod filters, especially with CV carbs. Beyond the drivability issues that they typically cause with the changed intake length and/or volume, they also can be problematic when riding in wet weather. To my surprise however, this bike ran pretty well as set up except for a slight rich hesitation at low rpm (cleaning up at around 5000rpm). 

This bike was a Craigslist find in Morrisville, NC. The previous owner had recently moved from Colorado where presumably the bike was purchased new. The individual I purchased it from claimed that he was the second owner of the Kaw and was in running condition when he bought it. It was dirty though... And the paint had seen some better days with the clear coat lifting off over the striping on the fuel tank. Additionally, the engine cases and the other aluminum parts had corroded and had that powdery white look to them. Another problem that kept the asking price down was the seam at the base of the operator's seat had come unsewn and needed attention. Otherwise, it seemed to be a pretty solid example of an early 1980's Kaw.  All the electrical parts items, including the low fuel light, worked as they should and it looked like this bike would be relatively easy to bring back to respectable shape. 

Ride report and more photos to come...