OzVMX Forum

Clubroom => Bike Talk => Topic started by: dodgee on January 06, 2013, 11:37:13 am

Title: gem reed
Post by: dodgee on January 06, 2013, 11:37:13 am
chasing a article on fitting a gem reed to a 73 cr250 honda.
have been told there is one around.
Title: Re: gem reed
Post by: JohnnyO on January 06, 2013, 12:14:02 pm
I used one dodgee on my '74 250, you need to cut 2 windows on the intake side of the piston. It makes a big difference, I may have an article somewhere.
Title: Re: gem reed
Post by: dodgee on January 06, 2013, 04:17:06 pm
thanks john,  remember what size carby you used
Title: Re: gem reed
Post by: JohnnyO on January 06, 2013, 04:58:36 pm
38 mikuni carb
Title: Re: gem reed
Post by: SON on January 06, 2013, 06:16:05 pm
Mugen made a piston, but they are rare.
Title: Re: gem reed
Post by: crs-and-rms on January 06, 2013, 06:49:29 pm
i put a gem on my tm 125 back in 75 or 76 it came with instructions on where to drill the holes in the piston wish i still had that bike and the instructions
Title: Re: gem reed
Post by: TeeBone on January 06, 2013, 08:49:17 pm
Before you do ANY piston mods, take the time to get in contact with Lozza!
Title: Re: gem reed
Post by: JohnnyO on January 06, 2013, 09:59:27 pm
Before you do ANY piston mods, take the time to get in contact with Lozza!
Why?? What's his claim to fame?
Title: Re: gem reed
Post by: TeeBone on January 06, 2013, 10:33:22 pm
Take the time to talk with him... ;)
Title: Re: gem reed
Post by: Rossvickicampbell on January 07, 2013, 09:21:28 am
now we had this discussion before didn't we - nothing Mugen for the 73/74 Hondas?

And yes - the GEM reed setup and properly modified pistons make a big difference to the performance.
Title: Re: gem reed
Post by: Lozza on January 09, 2013, 05:16:13 pm
chasing a article on fitting a gem reed to a 73 cr250 honda.
have been told there is one around.

To make the most of the reed , boyensen tunnels and a C/boost port needs to be cut in.
Title: Re: gem reed
Post by: dirttracker on January 09, 2013, 07:06:46 pm
put a early yz piston in it you will have to move the ring locator. you will have to put a extra port in the cylinder if you want it to work properly
Title: Re: gem reed
Post by: SON on January 09, 2013, 07:24:00 pm
with the YZ Piston there was a slight change to the deck height as well
worked good in the air cooled ATC250R as well