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I noticed the extra ports on the intake, which I’ve seen before, but not the straight coolant barb. Do you know what it came out of?

Aside from 250Rs, these engines were often ran in shift carts and adapted to work in all kinds of other crazy setups. Thirty-five plus years of people trying different things, you never know what you’ll see😆 I’ve even heard of people running the cylinder backwards as well (intake to the front, exhaust out the back).
 

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where did you see it? Im trying to figure out who did the port work on this cylinder, its quite extensive, the exhaust port is huge.

I received it with a bunch of loose R parts
Just from people in the past posting something similar, either here or Facebook, or possibly TRX250R.org. If you do some searches here, I think they’re called intake boost ports. I’m no porting expert.
 

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The boost ports are the ones going down toward the crank case. I don't know what there technically called but aftermarket cylinders have those extra upper ports as well. By the way your cylinder's an 86, the 85 doesn't have the bridge between the reed cage & coolant spigot. Looks like it's had a bit taken off the top too. You'll want to take some measurements before trying it out, it could be set up for a stroker.
 

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I don't think that's entirely true, I believe there are some 85 cylinders that have the bridge, possibly late production
I suppose thats possible but all 86 cylinder sleeves have an 85 stamped in them. I have an 85 atc cylinder, 86 atc cylinder & 2 86trx cylinders on the shelf that all have the 85 stamp. The only one thats different is the 86atc cylinder has p85p stamped into it. Likewise I have a cylinder that came from an 89 but it has 88 stamped on the sleeve.
 
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