Single Cylinder Re-Bore

Tried my hand at reboring a 125 cylinder head never done it befor... but it gave me a good excuse to use all my new tools ......
what seems to work for me ?
Finnishing..
No oil
90* lead angle (vertical) _|_
Doc: 0.01-0.02
RPM: 900
FEED: 0.0015 per/rev
(Bridgeport slowest quill feed^)
took me longer than usual to make this video been abit ill .......

[@DanKoning777]

I don't know what fascinates me more-the machine work, or all the opinions regarding what you
should/shouldn't do, use, or call things. Thanks for the video. God bless.

[@kcraig51]

If that boring head screws on to the arbor, when you spin them backwards, they can unscrew and...well, you get the picture. Also, try something like a .5 -1mm radius on the corner of the tool.

[@ChixWoman]

This channel is worth watching. Great work. Now just get a small engine that you can machine and get running again. Keep going!

[@allangles4020]

Thank you

[@petercunningham3469]

No oil 👍 and use a radius cutter form .I've even used a diamond point wheel dressing cutter on some harder bore materials with impressive results . 😊

[@canicemorrissey7313]

Nice work 👍

[@DontCallMeGarage]

@all angles, low speed on the downfeed should be .0015" per rev, mid should be .003"/rev, high .006"/rev

[@DontCallMeGarage]

you don't want a shiny finish on a cylinder wall, you need to hone to final size with a proper cross hatch for oil control and ring seating.

[@HM-Projects]

Well done, pretty good result. A rig for internal grinding / lapping may be needed to get better finishes.

[@DolezalPetr]

Hi, to get better results with these boring heads, just throw out the tools that come with it, they are crap, replace them with propper indexable lathe tools with good quality inserts.

[@billdoodson4232]

I'm not totaly sure on the specs for overboring a cylinder, but I would have checked what the actual size of the cylinder was before starting, against what original spec was. Then found what out what the smallest oversize piston was you could get for it, I'd then have overbored it to the correct size for that piston less a small allowance for honing. You'd then have an overbored cylinder you could sell on, unless you have the rest of the bike as well. Looks like a Honda 90 step through or similar.

[@gorak9000]

Seems like there's a problem between your bore gauge and the boring head - the bore gauge says your centered on the bore, yet the boring head is cutting like it's offset in the hole.

[@allangles4020]

It was slightly off but the first pass was only 0.02 mm and then cleared up at 0.04mm

[@robinwheatley4476]

It's a cylinder barrel not a head. Good result though.

[@pitmanncb4368]

dry no loob

[@gertkristensen6451]

dont use olie/coolant on carst iron .. and next time use toolbits steel .. grindet 30-45 degrees

[@billdoodson4232]

Yes I was going to say a correctly ground HSS cutter with no lubricant would have done a better job than carbide.