Pipe outlet diameter and pipe heat

[DKP]

So. I have a 2018 axys. With spi pipe and can. But also geared very low and clutching of corse. It snaps quick. I ride trees I need that. Love that. But I have a question on pipe outlet diameter. I believe mine is made for 800/850. It pulls much harder and faster to 3/4 throttle. Tps everything good and I have a fuel commander. So let's rule that out right away.

My issue is pipe temp and rpm. Say stop for a 10 min break. Or stuck etc. I let my engine warm to 88f always before moving. But. On first pull. 7850. Then will rise to 7900. Back off and stab again. 8000 and longer hold she climbs to 8250. Where I want it to be. Now. If you can keep on it. Every let off then full throttle within 5-10 sec will hit 8250 every time. Idle 30 sec or longer. 8000 first wot again.

It seems to take some time to get pipe heated fully. I've put the stock clamshell and insulation on too. That helped but. I am thinking pipe outlet size. Now I haven't taken mine back off yet to measure inner diameter of that to my stock 800 pipe. Never did it with stock at all. Fuel commander or not. Just noticeable less snap and power without. I just want my rpm's more consistent. But don't wana weld a sleeve in and make too small and melt my guts.

Insite and help would be awesome. Or if anyone has a stock 850 pipe to measure outlet ID. I could compare to my stock and my spi

 

[spoon]

I had similar issues on my Proclimb 800 with MBRP can. I made a drop in sleeve for my silencer to reduce diameter slightly to change backpressure. Easy to remove if results were not what I desired. Worked good though so I left it in until I changed silencers to one that had a little more restriction.

 

[DKP]

I had similar issues on my Proclimb 800 with MBRP can. I made a drop in sleeve for my silencer to reduce diameter slightly to change backpressure. Easy to remove if results were not what I desired. Worked good though so I left it in until I changed silencers to one that had a little more restriction.

That's kinda what I wsa thinking of doing. Did you sleeve the can outlet or the pipe outlet? From my understanding, the 'stinger' is the pipe convergence outlet. Not the can. And thus, there is where the sleeve should be located.

 

[spoon]

That's kinda what I wsa thinking of doing. Did you sleeve the can outlet or the pipe outlet? From my understanding, the 'stinger' is the pipe convergence outlet. Not the can. And thus, there is where the sleeve should be located.

Drop in sleeve in inlet of can so it directly restricts the pipe stinger. I have an exhaust bender and pressed a flare in end of sleeve so it would drop into can and sit just under exhaust donut. Went 1/8 " smaller diameter than pipe outlet with a 3" long sleeve.

 

[rdr99]

Used to use a nut welded to the pipe with a bolt thru it, with stacked washers to adjust it.