Any one try the new intake inserts from JS?

Define intake inserts . D-port 32 mm. , or the tap home reduction sleeves .
I have tapped home the 32 to 30 mm. sleeves with copper hi temp silicone , thinly applied and the fit was perfect . No issues .
 
There's a couple out there now. I'm running them in my 750 and there seems to be more punch all the way through the RPM range (and the exhaust note seems a little more expressive) but mine also have the benefit of a little cobra head porting. Floors for 30mm ports are currently being tested and they give more mid range punch but need a little cobra head shape to give increased top end. The 32 D shaped port floors don't need any porting unless you're on the track and want it all. Hopefully some people will post their feed back when more get out there. These raised floors are copies of the HD XR 750 port floors and that should tell you something.

Any one try the new intake inserts from JS?


The HD XR 750 raised floor we're copying:

Any one try the new intake inserts from JS?


Below is the HD XR cobra head shape. This sample is for full race, a little extreme and and is further than you need to go. You only have to take out approx 1mm on each side to make it higher and wider around the guide (blending in with the original shape at the manifold and the bowl).
Any one try the new intake inserts from JS?
 
And results?
I'm interested in the new D-port insert.
There's a couple out there now. I'm running them in my 750 and there seems to be more punch all the way through the RPM range (and the exhaust note seems a little more expressive) but mine also have the benefit of a little cobra head porting. Floors for 30mm ports are currently being tested and they give more mid range punch but need a little cobra head shape to give increased top end. The 32 D shaped port floors don't need any porting unless you're on the track and want it all. Hopefully some people will post their feed back when more get out there. These raised floors are copies of the HD XR 750 port floors and that should tell you something.

Any one try the new intake inserts from JS?


The HD XR 750 raised floor we're copying:

Any one try the new intake inserts from JS?


Below is the HD XR cobra head shape. This sample is for full race, a little extreme and and is further than you need to go. You only have to take out approx 1mm on each side to make it higher and wider around the guide (blending in with the original shape at the manifold and the bowl).
Any one try the new intake inserts from JS?
So you have some that fit all 750 commando heads, not just combat?
 
Right now they are only available for the 32mm RH4 and the 30mm RH10. 750s with 28.5mm ports have yet to happen and they will definitely need some porting and the Cobra head shape because of their small size. However those heads have the most potential because the ports can be raised at the manifold all the way through the guide and give the best flow. Porting diagrams will be provided. See the shoe I installed in my 750 with the elliptical ring for the raised port.
Any one try the new intake inserts from JS?
 
I just got a set for my RH4 head. I'm pleased with the fit and used Permatex's "The Right Stuff" to set them in place. I did a small amount of blending at the tip just to ensure a smooth transition but it was very minor. At the same time, I set up the exhaust inserts. I'll be curious to see what all this does to the carburetor jetting. I suspect I'll have to lean out a bit but we'll see. I also have a set of the RH10 inserts on the way. If the fit is anything like the RH4's, there should be a noticeable increase in flow. Mind you, I'm not doing this for outright power but more to see how efficient combustion will be.
 
I think the same way . Plugs pulled , after a long ride showed slightly darker , so I screwed richness idle adjuster out a tad on both carbs . Winter now so no more real time tests .
 
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