Reed box adventures
It all began when I read Richard Oxon's post on the sportbikes forum regarding a modded reed box (link to forum on links page). He said to cut otu the middle, sand the remainder flush, and install a single blue carbon reed for a 1/2HP gain. Not being one to leave a brand new bike alone, it was time to play with the reed box!
Not being an idiot, I ordered a new reed box, complete with blue carbon reed set, as I didn't want to slice up my old unit. But what's this?!?!?!? The new reed box comes with a SINGLE LARGE OPENING?!?!? It's pre-modded to exactly what Richard said to do!
The new reed box is on the left- not single LARGE opening- it came from the factory like this! The next pic is a side by side comparison- it's pretty dark in my stock reed box, but it is the 4-hole design with split carbon green reeds.
There was a 'surprise' waiting inside the new reed box though- some kind of air diverter:
I had no idea what purpose this serves- straightening the airflow maybe?
As you can see, the diverter-thing creates a restriction in the air path (left photo). I think it was designed for a 14mm carb, as that would probably be a near perfect fit with the small central hole this creates. With the diverter removed, we get a MUCH larger opening as seen on the right.
Here's the Mossbarger reed spacer I installed. It seems to work well for now- the true test will come later at the track. One bad side effect though- it moves the carb up and out, so your choke is now useless. not that I ever USE my choke in the first place, but it's something to keep in mind on DMs with race pipes.
It also seems ALL DM's, even the officials, come with fiberglass reeds, so if you want a slight kick, go for the carbon units. I have to say though, the fiberglass reeds do feel a lot smoother, so there is something you give up.
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