Want to Buy Cones Cones Cones

[mrfist9]

Hey guys Getting a bit cussum with my Jammer. Found a B1 style coffman pipe, but trying to adapt a straight cone to work for me.

The ask is does anyone have a loose/spare 5" cone? The coffmans 5, WC and stock seadoo 717 are 4.75. Sadly the seadoo one is the fitment I need. would love a spare coughman I could chop up

May just scour the earth and find a 5-4.75 adapter. Probably doesn't exist.

 

[kevbo]

I have wrapped a WC cone with wetted 2” fiberglass tape until it was 5”. It worked perfectly for years on my 650 coffmans pipe. I called coffmans in 2002 and the lady said they had one 650 pipe kit left but no more cones. She sold me that new kit minus a cone for $160. It’s still on that 650.

 

[WFO Speedracer]

If you are looking for a Seadoo cone, how many would you like ?

You could probably get a 5 to 4.5 silicone reducer and get it to stretch to 4.75 , you might have to boil it first though. I know www.Siliconeintakes.com carries them.

Pipe Reducer

Tube reducers and more.

www.siliconeintakes.com

 

[mrfist9]

If you are looking for a Seadoo cone, how many would you like ?

You could probably get a 5 to 4.5 silicone reducer and get it to stretch to 4.75 , you might have to boil it first though. I know www.Siliconeintakes.com carries them.

Pipe Reducer

Tube reducers and more.

www.siliconeintakes.com

If I go that route I'd be good with what I have
just would love the right coupler
I could also maybe stretch a 4.75 too the coffman

 

[WFO Speedracer]

Those are hard to find , I considered just getting the cones from Cone Engineering supply and making one out of stainless but I would have to find someone to tig them together and that's been an issue around here lately. You could also but the cones in mild steel and have someone powder coat them.

https://coneeng.com/pdf/cone%20list%20PDF.pdf

 

[mrfist9]

4.75"/5.00" Silicone Reducer Coupler, Black

www.roto-fab.com

holy crap

 

[WFO Speedracer]

Awesome sauce !

 

[mrfist9]

I'm also just overthinking it

Just shoved on a 4.75"
What could go wrong. Hope powers way up top

 

[WFO Speedracer]

It doesn't look like you can squeeze much more length in there another inch or two maybe ?

I have a Coffman pipe that someone removed the coupler and welded the cone to the pipe , it's also fairly short but it pulls pretty well on a 650 Kawi motor , that 650 Yammer ain't got no top end anyway unless someone has jacked with the porting on it.

 

[mrfist9]

It doesn't look like you can squeeze much more length in there another inch or two maybe ?

I have a Coffman pipe that someone removed the coupler and welded the cone to the pipe , it's also fairly short but it pulls pretty well on a 650 Kawi motor , that 650 Yammer ain't got no top end anyway unless someone has jacked with the porting on it.

I widened the ports a little bit
I'd love to get more length on it, but easy enough to swap out I wanna try this. Figure one could find a a Coffman cone full length if I'm patient

The cone length of this seadoo one is very similar to the 90deg one that came with the pipe fwiw

Looks more like a 650 pipe than a 701 to me too

 

[kevbo]

The coffmans Yamaha 650 pipe is shorter than their Kawasaki pipe in order to make any rpm with the Yamaha 650s 172 degree exhaust port. The longer Kawasaki version will rev up to 6500 rpm with a 180 degree port. The Yamaha version will rev to 6700 with the same 180 degree port. The stpck Jammar pump doesnt load the engine as much so a short pipe is probably okay. Just see how quickly the pipe hits and adjust its length or the impeller as required so there is no lag in throttle response.