Hello! Grateful to say I have more energy than ever for DTs again so I'm back to them in full swing. This cylinder I got off a parts bike needs to go for a rebore, I acquired an OEM 0.50 piston, but before sending it out I'm considering cleaning up the intake and exhaust ports (I am assuming I will have to chamfer the ports as well once it comes back from rebore)

My main question here is regarding the intake port...I hope the photos convey it well but intake port just isn't a direct shoot into the intake cylinder. about 80% of the way in it kicks up, has a sharp edge peak, and then comes back down. I would imagine that causes some weird flow.

Without particularly enlarging the intake, seeing as this engine will have a VM22 instead of a VM24 for at least the rest of the season, can I bring that peak down and smooth it out so that it's a direct shoot in? It's also just not symmetrical left to right haha. I knew these were coarse and unrefined but I've never spent this much time looking at them as I have now, finally having the courage to remove material from these cylinders. I compared it to a 125 cylinder I have sitting around that's open and my other 175s and they are all different but certainly much smoother. 

Guess I'm just looking for general insight, maybe some tips and tricks on smoothing it out while in there in terms of performance. I've done 2 stroke porting on mopeds in my time before and during my time away from DTs, but I just never had the cojones to take a file or dremel to a 600$ CAD starting-hard-to-get OEM cylinder. 

Dangit I type so much. Appreciate your patience!

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turned the lights off at the end of the night the other day and on my way out thought it was a charming shot to remember a 125  --> 175 rebuild/conversion by

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my little helper, loves being in the garage, goes crazy when we're not hanging out in there. I used to think he just wants to be in there because it's another locked door that he can't always access, but everytime I'd let him and go about my own stuff he'd be upset that I didn't go in with him haha. 

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and of course my original DT that started it all for me and a lot of my internet acquaintances, finally getting the love she deserves. Took me 7 years cut the swingarm out for some reason. It took me 30 minutes...but it took me 7 years haha. But it's all up from here I suppose, time to rebuild it. Just wanted to share!

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My laptop i'm on now won't do pics--too old like me lol but did see your inlet pic this morning o main computer.
I'd be the last one you should follow on porting as i just used to make them big for racing but using calculated dimensions for height & width & for port timing [although i guess within reason inlet timing doesn't matter much when there's a reed valve involved] but make the hole too big & the piston skirt will suffer.
I had the liner break off below the inlet but the jury is still out on whether the piston broke & caused it, or if the liner didn't have enough meet left at the inlet edges & fell of which destroyed the piston--& nearly me too.
Was a Suzuki 100 cylinder therefore not the same. So i'm no use at all.
Just ride it & enjoy it unless you want to do all the porting & modify it to some 'go-fast' specs including squeezing more compression out of it.
Rich Porting is on here sometimes with knowledgable advice.
I'll look at your other pics in the morning & look forward to seeing 'your little helper'.

I like your helper. I have a similar cat that howls like a dog if i go out the door to the shed & leave her behind.
She's a lot more timid than your one appears to be & doesn't get too close to the action.
Here's a couple of pics of my porting escapades from racing--what we called bucket racing or miniature roadracing--& had to be based on a 'non' competition motor so no YZ or RM compnents.
That was many years ago in crazy times for about 15 years. Even closed the streets in town a couple of time but mostly industrial areas or the airforce base where the clever engineering types were 'right' into it with mods like ya wouldn't even think of. They had all the gear to do it with too.
These two pics show the cylinder liner that broke off while on full song through a sweeping corner plus between two other riders haha--survived.
Other pic is a reed block of my 360 yam welded on to the Suzy 100 farm bike cylinder & as usual i grossly overported it. Went like stink between blowing up problems. So i recommend NOT doing what i do.
photos.app.goo.gl/NMmdLaSr3N5utY9UA
photos.app.goo.gl/s2rMmqvG81mqRK2NA
photos.app.goo.gl/sxhkJ1KpRfktEKwA6