oh and just realised this is in the wrong section. Can a moderator please move it to the chassis section? thanks

Hey guys so I need some input please.

I have to widen my frame at the pivot point to accept a wider swingarm. It's about 45mm wider total. So I need 22.5mm (or about 7/8") either side if I keep things central.

The frame doesn't have enough metal to remove that much without weakening the pivot points. It's a shaft drive so the pivot points are also threaded to hold the pivot pin/bolts that hold the swingarm. Here are some pics so you can see what I'm referring to. The whole issue is complicated by the fact that 3 tubes join at this point of the frame and there is like a folded gusset over the inside and outside of the joint. What do you think would be the best way to widen the frame?



a) Cut the cross supports and stretch the frame at the pivot point, then weld in new cross supports and bracing? This may misalign the threaded pivot points from being perfectly parrallel.
b) Add material to the outside of the pivot points which will allow me to remove the required amount from the inside of the pivot point Downside is the added material won't be directly under the tubular sections that join at this location, but rather "next to them"
c) Cut out the entire pivot point and insert completely new section that can be laser cut from thick steel plating, with locating points that go into the tubular steel before welding it together. Then thread the new steel plating for the pivot bolts. (let me know if I need to draw something to explain this better)

Back at it again here and going to drive this across the finish line. I've decided I'm going to move the petcock location back a half inch since I have to redo the tank anyway. Fixed a headlight wiring issue, wired in the high beam indicator light and I believe that wraps up the wiring. After riding it late last season, the shock seals must have given out and the rear shock puked oil all over the garage floor. I've just finished replacing it with a ZR7s rear shock. Had to narrow the top shock mount bushing by 2mm and add two washers and a longer bolt on the lower mount. As this shock is 1/2 longer, I'm going to have to flip the chain adjustment bushings and move the axle towards the top of the swingarm or I can't use the center stand. The wheel and tire now set just a bit lower than the bottom of the center stand. Which brings up a question:
What is the best way to rotate the chain adjusters on an 83 to 85 GPz 750? I have to pound the bloody hell out of the to get them to budge. Pounding on things rubs my fur the wrong way. Yes I've loosened clamping bolts at the rear of the swingarm. What a massive PITA. Can't believe racing teams put up with this crap.

That indent you describe is a common problem. It is the result of damage known as "brinelling" see en.wikipedia.org/wiki/Brinelling .

There is no repair for the problem other than replacing the bearings. You should replace the steering stem bearings with tapered roller bearings. The folks at www.allballsracing.com should be able to tell you exactly which ones you need for your bike. I installed their tapered roller bearings in my KZ650-C1 years ago and have found them to be vastly superior to the original ball bearings that came in my bike's steering stem.

Brinelling is the result of the balls making impressions in the races when the bike hits a bump or by the bearing pressure squeezing the balls against the races. If it is somewhat severe it can cause notchiness in the steering and sometimes you can feel the front end tend to seek being pointed straight ahead. This is sometimes referred to as "indexed steering." When these conditions occur the front can develop a bit of a low speed wobble (at least this was the case on my KZ650).

Tapered roller bearings give much more bearing surface area than loose ball bearings. Think of the bearing contact area of a tapered roller as a "stripe" for each roller that goes from one end of the roller to the other where the roller contacts the races. Then consider the bearing contact area of a ball as a small "spot" for each ball where the ball contacts the races. The total contact area of the roller bearing "stripes" is much greater than that of the ball bearing "spots." This additional contact area spreads the load reducing the pounds per square inch of pressure at the contact area and eliminates the "dimpling" that is common on ball bearing steering stem races. This reduced pressure also makes tapered roller bearings last longer than ball bearings mainly because the races are much less affected. The reason is easy to visualize when you consider the roller bearings making contact with the full width of the bearing races compared to the ball bearings running in a single line near the center of the races.

That may or may not be the total cause of the wandering, but you should not ignore it. If you have time, a torque wrench, and some other common tools and follow the instructions in the Kawasaki Service Manual you can replace the steering stem bearings yourself.

Here's how I did mine several years ago:

To do this work I had to remove the front forks. I did the work in my basement during the winter. I laid a 4’ x 8’ sheet of 7/8” hardboard on the floor and parked the bike on it. This was to protect the basement carpet from possible stains, and it also enabled me to very securely anchor the rear of the bike while the front forks were removed. With the bike on the center stand, I put a small bottle jack under the front of the engine with a piece of wood between the jack piston and the oil pan to protect the oil pan (image below). I jacked up the front of the bike until the rear wheel came in contact with the hardboard. Then I ran a cargo strap through the swing arm, attached the “S” hooks on the ends of the strap to the edge of the hardboard, and took the slack out of the strap. That strap made the bike very secure. You may want to use this same method if you remove your forks.
Ed

Longer term plans is to modify a GL1800 single sided swingarm and run it upsdie down to enable a 190 tyre and different wheels with a monoshock. The goldwing arm is 4.5cm wider at the pivot so it will take some substantial fabrication, and modified offset (car) wheel narrowed to 5.5 or 6" in order to get things back into alignment, But I'll look back into this at a later stage.

Ok so small updates. Been sourcing parts to get this underway.

The engine is with a Kawasaki engine builder. Getting a refresh with new OEM crank and rod bearings. The cruizin image pistons arrived too and they look good. Almost forged.

I've also been struggling with the direction of the wheels, tyres, possible chain conversion etc. In the end it looks like I'm going with the KZ1000 swingarm. I also have a KZ1100 swingarm but the st1000 has a cleaner look. It also uses a brake caliper that attaches to the swingarm vs a torque brace like the gt750 and the kz1100.

The 1000 swingarms are 30mm longer and I personally think it makes a nice difference to the stance of the bike. They are narrower at the pivot point which I still have to resolve, while trying to keep the wheel and drive shaft in the correct locations.

The 1000 rim is 17x2.5 vs 18x2.15 of the 750. I'm able to run a 150/70/17 tyre, but it's cutting it fine at the swingarm. The 150 tyre doesn't look any wider than the 130 to be honest. But it has a more rounded profile which should help handling. Could also be cause it's on a tiny 2.5 rim....

Anyways, here are some pics. [attachment=105659]

Pictures 4 & 5 below show a comparison between my homemade modified bits with the authentic JIS bits.

PICTURE 4


PICTURE 5



Here's a pic comparing JIS bits to Phillips bits. Ed




Before reaching for that wrench or ratchet consider the following. The bolts are steel, but your engine and front forks are aluminum. The bolts are much tougher than the aluminum and if over tightened will strip the aluminum threads. Although these can be repaired, preventing damage by applying proper torque will save you grief, time, and money. Tightening fasteners properly requires torque wrenches. Various vendors, including Snap-on, CDI, Sears, etc., market torque wrenches. The two most popular types are the bar type and micrometer type. Either will work, but the micrometer type is a bit easier to use, especially if you are tightening several fasteners with the same torque - such as cylinder head covers. You will need a torque wrench calibrated in INCH POUNDS for many of the bolts. You will also need a torque wrench calibrated in FOOT POUNDS for the larger bolts. Don't try to use the foot pounds wrench on the smaller bolts as it will not be sensitive enough at low torque settings to provide accurate torque. There are many fasteners that require low torque. These include such things as 6mm oil pan bolts, cylinder head cover bolts, etc. for which the torque in 61-78 inch pounds. These low torque bolts require a wrench that is accurate at low settings and this wrench should be graduated in inch pounds. In addition, there are numerous high torque fasteners such as the front axle nuts (51 - 65 foot pounds) or swing arm pivot shaft nuts (58 - 87 foot pounds). These require a wrench that is accurate at higher settings; this wrench should be graduated in foot pounds. Using the proper torque wrenches to correctly tighten fasteners will help prevent damage and contribute to a safe bike. The Kawasaki Service Manual will list the various torque specs for the bolts. I suggest you get the manual before buying the torque wrenches so you can decide which wrenches best meet the torque specs.

Consider buying a can of Kroil penetrating oil and use it to soak stubborn fasteners for a couple days before trying to loosen them. Remember, the original screws and bolts were installed on your bike when Jimmy Carter was President, so many of them may be hard to remove. Kroil can be bought online, at guns shows, and at some other venues.


MOTOR OIL
The ingredients in oils have changed over the years. For example, today's Castrol GTX (and pretty much all AUTOMOBILE oil) is not the same as it was in the 1980's. Back then it worked great in KZ bikes, but things have changed. Zinc and phosphorus additives (ZDDP), important to protect engine components from metal to metal contact, has been reduced since it’s been found to shorten catalytic converter life. Today’s auto oils contain about ½ the ZDDP they used to and different additives have been developed as substitutes. Unfortunately, some of these newer additives, in particular molybdenum disulfide, don’t get along with the wet clutches in our bikes. Newer oils, especially those labeled “Energy Conserving” (EC), which have a high quantity of friction reducing additives, should be avoided. These oils work fine in automobiles but there are better choices for motorcycles.

KZ bikes need oil which is suitable for wet clutches. That distinction was defined by the Japanese Engine Oil Standards Implementation Panel (JASO), and can be noted by oils that meet the "4T” (4 cycle) specification, MA (wet clutch) classification. These oils, which include various synthetic, semi-synthetic, and non-synthetic oils, are sold as specific motorcycle oils. Another type of oil which works well in our bikes is diesel engine oil. These oils are governed by the API (American Petroleum Institute) CI-4/CJ-4 spec and don’t contain clutch-damaging EC additives. You can even purchase Shell Rotella oil which holds a “JASO-MA” certification assuring it will get along well with your wet clutch. All of these newer oils have a reduced ZDDP level too (about 1/3 less than before instead of ½ like the auto oils) but the substitute additives get along better with our bikes needs than automotive oil. Oils that do not hold the JASO-MA rating have either failed the wet clutch test or have not been tested for use in engines with wet clutches. Good luck with the bike! Ed

yup......so while i got my bike stripped down to a bare frame, de-rusted it, checked welds, added welds in places i thought needed total welding.....i got to browsing craigslist for parts.....mostly in the frontal area..........in a few hours i will have a donor bike, a 1983 GPZ750. so...heres the plan. gonna swap the front fork over, convert the 550 frame to taper bearings, a friend is gonna cut off and weld in the uni-track mount from the gpz frame and weld it to the 550's frame, install the swing arm set up and the "new" disk brakes and hooooopefuly have a rideable bike within the next few millenia. will post pix of the progress. but today......when it warms up some.....primer and paint on the frame!

Setton wrote:

Ed may still be on the right path. Could be hitting inside the engine sprocket cover

If that were the case, wouldn't the sound happen regardless of whether or not throttle is being applied?

...

No.
Consider this -

When the throttle is being applied with the tranny in gear the engine sprocket is pulling the top length of the chain taut as it pulls on the drive sprocket. When that happens all the slack in the drive chain ends up on the bottom length of the chain. This extra slack in the bottom length of the chain can cause the chain to rub things if the chain has too much slack in it.

One word of caution though - do NOT adjust the chain such that there is no slack in it. Doing that will very quickly ruin a chain because it needs some slack to cope with the fact that as the rear axle rises to a point where the axle, engine sprocket center, and swing arm pivot are aligned the distance between the sprockets increase. If the chain is adjusted with insufficient slack the chain will stretch and be damaged. Be sure to follow the instructions in the Kawasaki Service Manual or the bike's Owner's Manual for adjusting the chain. Ed

From previous research width between the swingarm pivots for the KZ400 is 8.5 inches. Width for the larger KZ bikes ( KZ650 and KZ750 twin confirmed, I assume others are the same, not sure about KZ550 ) is 9" or approx 228.5mm. The GSXR 750 should be a good fit. It looks like some of the VFRs will work too. I'd also look for R6 swingarm specs too.

Hello jfarhanbod
Here some charts for swing arms,shocks and forks.





Translation

Breite Schwinge Vo. = width swing arm to frame (pivot diameter)
Breite Schwinge Hi. = width swing arm for rear wheel + all components, sprocket holder/rear brake (pivot diameter)

Michael