Derbi Flat Reed Exhaust port

shman shmilroy /

AY,

New to Derbis. Has this exhaust port on a '89 Variant Sport Flat reed been altered from stock? To my eye it looks like it may have been opened up a little the last 4-6mm from the external face of exhaust port into the exhaust duct ... I'm just not at all familiar with Derbs. <3.(edited)

20200107_165345.jpg
Capture.JPG

Re: Derbi Flat Reed Exhaust port

shman shmilroy /

is it flatreed or flat reed? asking for future search key word .(edited)

Re: Derbi Flat Reed Exhaust port

Brandon Weiss (Detective brandon to you) /

I haven't seen a standard moped flange that looks like that, looks like it was altered for use with a slip flange with a conical joint? Kind of like some car exhaust joints? Or maybe a crush ring of some kind.

Re: Derbi Flat Reed Exhaust port

Dirty30 Dillon /

A ton of Derbi FR topends ran a cone header like that, from the factory. Just a standard cylinder.

Re: Derbi Flat Reed Exhaust port

Brandon Weiss (Detective brandon to you) /

> Dirty30 Dillon Wrote:

> -------------------------------------------------------

> A ton of Derbi FR topends ran a cone header like that, from the factory.

> Just a standard cylinder.

That's interesting, I wonder what the header looked like

Re: Derbi Flat Reed Exhaust port

shman shmilroy /

I'll get a pic later.

Re: Derbi Flat Reed Exhaust port

Dirty30 Dillon /

> Brandon Weiss (Detective brandon to you) Wrote:

> -------------------------------------------------------

> > Dirty30 Dillon Wrote:

>

> > -------------------------------------------------------

>

> > A ton of Derbi FR topends ran a cone header like that, from the

> factory.

>

> > Just a standard cylinder.

>

> That's interesting, I wonder what the header looked like

They had a loose flange, like hobbit exhaust, and the lip matched that cone shape

Re: Derbi Flat Reed Exhaust port

shman shmilroy /

yup.

Capture1.PNG
Capture2.PNG

Re: Derbi Flat Reed Exhaust port

I bet you could use a copper ring the seal it up with normal exhaust

Re: Derbi Flat Reed Exhaust port

shman shmilroy /

I'm at the point of exhaust reinstall, and I'm lost on how the gasket is supposed to fit on? D30, is that cone supposed to fit all the way flush into to the cylinder body? or is the cone supposed to act as a sort of tight seating angle eliminating the need for a gasket?

right now my cone is not flush.. ill clean it and smooth out any rough patches.

Re: Derbi Flat Reed Exhaust port

Dirty30 Dillon /

As far as I recall, it is meant to be a taper seal. I didn't have any gasket material in mine by the time I got it, but that def doesn't mean it wasn't supposed to be there.

« Go to Topic — end of thread

Want to post in this forum? We'd love to have you join the discussion, but first:

Login or Create Account