Frames?

See my "'78 KZ1000 Stage III Project" signature link below for pictures of the frame that I just got back from my welder last week.

Fossil wrote:

An upper engine mount will stiffen up the frame. Has anyone come across a diagram of this since it was lasted discussed? If I remember correctly, wireman mentioned there was an illustraion in an early Clymers manual.

it was either clymers or haynes cant remember which used to have the hot rod section in back.ive got a plan drawn up in my head for a set of top motor mounts using plates in place of the origional smog control covers on the 79 and newer heads/valvecover just need to drive across the bridge to my favorite metal place.the only problem is anytime i go to buy one thing i always walk out of there with $500.00 worth of extra metal for future projects!anybody else have that problem?:S :blink: :woohoo:

BohicaBob wrote:

See my "'78 KZ1000 Stage III Project" signature link below for pictures of the frame that I just got back from my welder last week.

damn that looks good bob !im fitting all 4 of my coils underseat where battery box used to be mounted so im going to fab a plate mounts between origional coil mounts and doubles as a mounting point for my top motor mounts.i was thinking about putting a brace behind where the carbs normally go like yours is but i think im going to make it removable so its easier to work on other stuff if i need to;)

Thanks. The frame reinforcement, plus heavy duty engine bolts and engine-to-frame plates (like Kosman's) make all the difference in the world, especially on higher-than-stock powered Z1s and KZs.

so what are you planning motorwise to go with all that new found stiffness ?

Either 1075 cc or 1197 cc MTC piston kit, Web 110 cams, 37.5/31 mm SS valves, mildly ported head, Mikuni 34 mm Flatslides, Dyna 2000, Kerker K45 pipe, Falicon crank, street-undercut transmission, Tsubaki cam chain, etc.

sounds like a good plan!:evil:

Frame looks nice and stiff now Bob.Just wondered why you only put 1 diagnal brace under the seat area behind the carbs,instead of 2 like an x? I'm just putting a zrx swing arm on mine now.I like this Idea.I never thought about the extra stress hear now with a stronger swing arm.I think I'll add this too. I should also double plate the sheet metal at the neck as well. I have most of the other bracing now.

the stock swingarms are about as stiff as a wet noodle,a stiffer swingarm will put more pressure on other areas in the chain you just have to beef as you go.

Bob, the welds look killer! Have you riden any bikes after the kosman brace/bolt kits have been intstalled? I know you like others have said it makes a big differance is that speculative or conclusive, just wondering what the feel is afterwards? I have purchased both for my 75 Z1 turbo project that I have fitted a 99 busa front end and working on the 03 GSX-R swing arm and mono shock. I am hoping to end up with something that can actually be rode quickly through the twisties am I dreaming?

Peace&Love:silly: , Darren

Post edited by: kyradawg, at: 2006/12/08 17:26

mark1122: The bracing pieces welded to the frame behind the carb area is part of the Kosman Z1/KZ Frame Kit. See the last picture in the third link in my signature which is a schematic of where the various pieces to this Kosman kit go on the frame.

kyradawg: My experience with braced frames comes from the experiences of others as well as myself. You are not dreaming, you can improve these old frames significantly. But even with all the bracing, these old bike frames will not be like those on 2006 Sportbikes.

I hot-rodded my '73 Z1-900 years ago but I did not brace the frame, at least at first. This bike was not fun to ride at speed. When shifting into 2nd gear from 1st gear at 10,500 rpm, for example, you could not help but notice how the frame and swingarm flexed as the bike sort of 'crabbed' down the road, the swingarm was being pulled one way and parts of the frame were being twisted in other ways. Bracing and improved suspension really helped this bike. The bike then stayed where I put it without 'complaining' to me via the sometimes vague or uncertain feedback that I used to receive when I pushed the bike into corners at higher speeds.

In my Stage III project bike, I sprung for the Kosman Frame Kit rather than making my own frame brace kit (which I did for my '73 Z1-900).

What about bracing for my bike? I know Kawasaki made changes to the KZ650 frame based on what they learned from the Z1 frame's shortcomings, then when they came out with the 750/4 they made further changes based on what they'd learned from the 650. So if I wanted to improve on what I have, what areas would I look to gusset?