OzVMX Forum

Marque Remarks => Yamaha => Topic started by: mboddy on July 04, 2008, 04:51:04 pm

Title: YZ400D/E with DG pipe - what jetting changes
Post by: mboddy on July 04, 2008, 04:51:04 pm

Has anyone here fitted the DG pipe to the YZ400D/E?
What jetting changes did you make?

Title: Re: YZ400D/E with DG pipe - what jetting changes
Post by: Tim754 on July 07, 2008, 08:17:43 pm

Mboddy Looks like plug chops* are the go. Tim  * hoping you know what that is of course. Cheers and happy jet setting Tim.

Title: Re: YZ400D/E with DG pipe - what jetting changes
Post by: crs-and-rms on July 07, 2008, 08:29:16 pm

id go 1  or 2 sizes up on the main jet and richen it then do plug chops or checks .better to start of richer than lean

Title: Re: YZ400D/E with DG pipe - what jetting changes
Post by: mboddy on July 07, 2008, 11:12:57 pm

Yes. I know all about plug chops. Been fitting different carbies since I was 12.
I was just hoping someone else had done it to give me a better starting point.

Title: Re: YZ400D/E with DG pipe - what jetting changes
Post by: E74 on July 08, 2008, 04:56:56 pm

what the hell are plug chops?

Title: Re: YZ400D/E with DG pipe - what jetting changes
Post by: IT490K on February 04, 2009, 12:00:30 am

Quote from: mboddy on July 04, 2008, 04:51:04 pm

Has anyone here fitted the DG pipe to the YZ400D/E?
What jetting changes did you make?

Mark,

I am curious as to what jetting changes you made and what ended up
working for you with the DG pipe. Do tell.

Cheers

Jock

Title: Re: YZ400D/E with DG pipe - what jetting changes
Post by: mboddy on February 04, 2009, 07:39:52 am

Ended up with 380 main and P6 nozzle. Standard is 350 and P4.
Reeds are Boyesens on Honda blocks with stops.
Airbox cover is cut like YZ400D. Uni filter.
Thinner head gasket.
Fuel oil mix 24/1.

I have now fitted a YZ400D piston and so I'll try the Q0 nozzle again and a 400 main and do it all again.

Title: Re: YZ400D/E with DG pipe - what jetting changes
Post by: Marc.com on February 04, 2009, 09:02:06 am

Quote from: E74 on July 08, 2008, 04:56:56 pm

what the hell are plug chops?

you start with a nice clean (or new ) spark plug, run the engine at full throttle de[ending on where you are tuning in the range and then hit the kill switch and coast to a halt. The you whip out the hot plug and 'read it'. If it is covered in black soot you are too rich, covered in Aluminum you are too lean  ;)