FX-1 What pipe?

OK, picked me up a 650sx pipe, I need a manifold now, there is a coffman's on ebay for 100 bux, is that about correct or is there a cheaper source? I have the tools and no problem doing the port matching, but I would like to have it matched before I break down the old stock pipe. Is the cyl to mani gasket close enough as guide to port the manifold? I would like to have it done ahead of time so I can have a better back to back compare.

my ski looks bone stock except; modified stock head, primer, some screens removed from stock F/A, modified rev limiter, solas impeller, grate & plate, big bilge (850gpm i think), still sissy lavender with stock graphics...

On the cheat pipe dry out- any one completely plug the head pipe injection hole then inject water at the current "drain" location (jetted)?

plans after modified KawaBpipemann's exhaust: 83mm pistons, finger port cases, clean up port castings, increase blow down T/A, re mod head for 83mm.

Who can get me some engine specs? I need:
Exhaust Open (either degrees or mm from TDC)
Rod length
stroke

I will use that to see what length if any to add to the pip mid section.


Read post 10 to find a cheaper source than the ebay deal.

I gasket matched my cyl ports before I done the mani. The stock 701 exhaust cyl ports are smaller than the gasket.

The pump mod is a must for anything over stock. I done my kawi pump for around $250

I pulled the 1/4 brass fitting on the head pipe and jb welded it up. I just filled/drilled the head pipe coolant hole to 1/8", its up inside the head pipe. That one coolant hole kept my pipe cool enough, I never melted a coupler or hose. Some add a line to the stinger but mine was fine without.

On my sn I had to grind a little off of the back of the mount where you mount the pipe to the mani not sure if you will have to on a fx1. The 650sx pipe bracket doesnt match the threaded hole on the coffman mani if you use the rubber bushing. I removed the rubber bushing and used a yamaha motor mount bolt/washers and it worked well to keep the pipe from thrashing around. You will also have to come up with a piece of hose to make the stinger end fit the yamaha waterbox hose. I think the yamaha hose is about 2" whereas the kawi hose is around 1 3/4". Just get a piece of 1 3/4 hose and put it on the inside of your yamaha hose. Works fine.
 
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2strok4fun

chris w
Location
SoCal & Havasu
I tried the coffman's route, spoke to Pam they sold all their stock and that is the guy selling on ebay. My wife had a 650sx that I had built mild using the stock pipe, so I am familiar with that pipe as well as drying it. It ran well, handled like____ well a 650sx...
 

kustumk31

woah yeah
Location
white lake mi
she sold them all to one guy and is giving out his number... i mentioned the site (x-h20) and he said " yeah they all hate me on there" don't know why but i ordered a mani from him!

How do i bump my timing? the links in post 5 said they bumped it?
where and how is this done??
 
Location
PA
i'm running a moded 650sx exhaust on my stock 62t engine this year and was wondering if you guys are rejetting the carbs when installing the mod pipe?
 
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