Header quick release mod? Dumb question alert!

I'm finally getting some motivation to get my GPz rebuilt. I will be using a ZR7S header again when I do so. (A ZR7 head as well as a matter of fact. I buggered up my head after I bought it and the only easy to find, affordable replacement option is the ZR7 which is fine with me.)

Anyway, the collector and mid-pipe get in the way of the oil plug and filter so I would like to do a quick release mod but I'm not exactly sure of the proper way to go about it. OK, weld on attach point for springs, I got that but what do you use for the header washers? Use standard washers, Fiber, something else? What options there for anchoring it to the head. I've seen everything from Hooking the srings to standard collars to loops welded on the collar bolts what works best?

At the head you need to create stubs that bolt to the head as normal but then have the down pipes a slip on fit to these using springs to retain.
The flanges use stock exhaust gaskets and stay on the head whilst the header pipes are a snug slip fit and use no sealer or gaskets.
You simply need to squarely cut the headers around 1.5 inch from the flanges and use four short sections of larger diameter tube to weld to the down pipes to create the slip on function.
After that you just need to weld on some tags for the springs.
Just trying to spring fit the entire exhaust to the head wont work.

Thanks! That makes sense.

I can easily do that at work! It looks like that would work better than those that seem to not to use the flanges. Or are they using flanges that don't protrude past the retainers?

All slip ons for most Jap road bikes use flanges bolted to the head with stubs that either slip in or over the pipes.
The pipes that slip directly into the head castings are early stuff like triumphs, bsa's , Enfields etc etc or race 2 strokes, TZ's / Motocross bikes which slip over a cast stub that is part of the barrel and have heat resistant 'O' rings in the header to form a seal.

Thanks, I knew I was missing something. The gears are spinning in my head now on how I'd like to set it up.

Wow that bike looks nice. Can you post more pics of that. The front fender is sweet

barney wrote: Wow that bike looks nice. Can you post more pics of that. The front fender is sweet

Z900 café build thread is here.
www.kzrider.com/forum/11-projects/395445...percharged-who-knows

Any recommendations on springs to use?

Material for the flanges? I think I can get 6061 or 7075 aluminum or 17-4 stainless in big enough diameter at work. Otherwise, I'll have to buy my own material. :whistle:

I just used what exhaust bits I had lying around but they are from salvaged stock stainless systems from a zx9r and R6.
The springs are stainless exhaust springs off Ebay.

I checked a few things and I definitely don't want to use the aluminum. The 17-4 has too high of a carbon content.

I did a quick check on prices of 304 bar stock and it's not too bad,

Did you use some sort of lube when you installed the down pipes so they wouldn't seize?

No! you don't generally use any lube just slip them on dry.
They do get a bit of blow by carbon build up in the joint which actually helps seal the pipe and if left a long time can make them a bit tight on removal but a bit of a jiggle and maybe a tap with a mallet if they are stuck is all that usually needed.
You could give the stubs a wipe round with some copper grease which may or may not help with future removal but i've never needed it.

Thanks, I know your bikes are track and drag bikes so I might put a dab of copper grease on to be safe since this will be as close to a daily driver as possible. I took some measurements off the header I just got off ebay and worked out a design for the sleeves. These wont protrude past the collars like yours do.