The 110 Adventures.

Can you link to or give a better description as to what you used to polish the head?
Back on page #2.
Akin to this.
 
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Can you link to or give a better description as to what you used to polish the head?
Yeah, I can link you to what I use. If you order these you will have a supply to last you for many many many engines to come.

I first used these abrasive scotchbrite wheels that start at 180 grit and go to 1000 grit to get it to a state where you can then use polishing compounds. The type that Chainlube posted also work well. I just like these because they also fit into ports rather well. Makes polishing up an exhaust port rather easy.

I then use Polishing compound just like Karl stated, with some felt polishing pads
Pads:

Compound:


I prefer the smaller stuff like this when working on these little engines because it helps get into small spaces better. As Karl also said, there are many types and sizes of polishing wheels and pads, from tiny rotary tool to huge bench grinder sized units. Just depends on what you are doing or wanting to polish. For these tiny little engines, I find this stuff to be more than sufficient.
 
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Nothing picture wise to share. I've been preoccupied with a new job and a change of schedule that my work has been minimal on this project. I am currently working on removing the lips from the ports that need to be removed and then I can clean it up and take new timing numbers before I attempt to change any of the ports.

Also still trying to work out the best way to get at the upper transfers effectively without spending a lot of money on a right angle tool or a dental drill that will take forever to remove the material needed (also a bit pricey).

My one real observation that I will make about the cylinder is the iron liner itself. As far as iron goes, this is some pretty soft stuff that cuts easily with my single cut burrs. I was afraid of ruining the burrs, but as long as you keep them oiled it cuts rather easy.
 
With the way that liner fits in the casting, you might want to check those #s before you clean too much up. You could be just smoothing with a file.

I have a handful of those little diamond files, but they are very time consuming.
 
With the way that liner fits in the casting, you might want to check those #s before you clean too much up. You could be just smoothing with a file.

I have a handful of those little diamond files, but they are very time consuming.
the way the lips protrude into the ports, and the already pathetic nature of the port timing, they can only improve in this case. I already have the timing numbers of the liner pre-cleanup.
 
the way the lips protrude into the ports, and the already pathetic nature of the port timing, they can only improve in this case. I already have the timing numbers of the liner pre-cleanup.
Wasn't sure what you did already, but with the way those edges on the ports look, kinda like a poorly sharpened saw, thought it might be hard to get a good number.
 
Wasn't sure what you did already, but with the way those edges on the ports look, kinda like a poorly sharpened saw, thought it might be hard to get a good number.
The intake and exhaust ports are more than able to be adjusted for desired timing numbers. It is mainly the upper transfers that really let the whole thing down. With adding a second base gasket and removing the lips I can get the transfer port duration to about 116-117 degrees. I would love to be able to at least get that number to 120 degrees to match the peak power RPM I want to tune the intake and exhaust timing for.

The only thing that kind of lets the exhaust port down is the piston sticking up above the floor of the port a few millimeters which will be a point of turbulence. Much like the lip from the top of the intake port, I am thinking about using some reinforced epoxy (aka JB Weld) to build a ramp to help with reducing that turbulence. I can then re-shape both ports to restore area and improve the timing figures.
 
I haven't forgotten about this little project, but I have just been so busy with other things that it kind of took a back seat for a bit. I started to get a little bit more work done on the ports. At this point I am focusing on removing the iron sleeve overhangs on the transfers and exhaust ports. Once that is done I am going to do a little create JB welding on all 4 ports to reduce turbulence and try to shape airflow.

I have decided to aim for the following numbers after doing some measuring, thinking, and evaluation of the cylinder and ports.

Exhaust - Still going for the opening at 100ATDC and 160 total duration. (current work in progress)

Transfer ports - 2 base gaskets and the overhangs removed has given me 116 degrees of total duration. With the transfers opening 122ATDC

This will give me a blowdown of 22 degrees which lands it much closer to the power band of the rest of the port timings and durations.

Intake - I am still undecided. A part of me is considering dropping the floor of the intake port to match the height of the inlet. This will increase my intake timing from 62BTDC to 66BTDC increasing the duration from 124 degrees to 132 degrees which is a bit aggressive. This has me considering a window and reed or third transfer and reed setup.

I am open to criticisms or suggestions. I don't claim to be the most well versed builder so if anybody thinks my numbers could use some tweaking let me know. My main goal is to try and land my power peak somewhere around 6000rpm and to run this motor with a clone pipe with the long header.
 
(Part 2)
Just to kind of break things up I am going to try and split this up a little. This next section is mainly going to be about the Transfers and their alignment.

To put it mildly, the transfers are a mess. Looking down the cylinder at BDC in this picture. You can kind of see the top of the lower edge of the upper transfers here. The piston Crown sticks above that a little bit, by a couple of millimeters. The sides and roof of the upper transfers are larger than the port cut into the iron sleeve. Amazingly well centered unlike the intake and exhaust, but leaving a 2-ish millimeter edge all around. That does mean some transfer duration can be recovered with just a bit of grinding, and the lip on the side means it is possible to play a little magic to try and angle the transfer charge more into the intake side instead of straight out, which is kind of nice. I need to look into some sort of right angle solution to be able to get in there better than my flex shaft will allow to really be able to do anything serious though. It's also worth noting that the cross hatch on the cylinder is pretty faint to non-existant as well, meaning this thing would have likely never sealed the rings. You can see how narrow that exhaust passage is too as a nice side bonus.


But wait! There's more!

The lower transfers! More specifically all of the alignment issues at the lower transfers... which is literally everything as far as I can tell.
Case to cylinder transfer alignment? The front side of both is actually pretty darn close, maybe the slightest bit of a lip, but not much. The gasket overhangs a bit though, so it needs a trim. The rear on both side is just a plethora of bad. Case to cylinder alignment is easily off 1/8th of an inch, but surprisingly the gasket lines up relatively well with the cylinder side. The iron sleeve cutaway for the transfers is smaller than the ports by quite a bit. I think it would be worth cutting it back to match the actual port width and trimming back the piston to match the sleeve. Maybe it wouldn't make much of a difference either. Who knows.



I will say this, the case for this engine is pretty beefy in terms of thickness, so it definitely has plenty of room to work with if you wanted to try a bit of case flowing.

Speaking of beefy cases, I do think this bottom end would be a decent platform to try a MS660 build with. The case opening for the jug and piston on this engine is 57.8mm, which means it can clear a 56mm big bore piston. The deck surface is pretty chunky as well. The only downside is, my theory about the stud pattern is wrong. Even though the spacing is 60mm, the holes would still need to be filled in and new holes drilled. This is more or less how the MS660 pattern lines up with the LD110 pattern, and as you can see, there is plenty of deck to work with. to do so.



And yes, it does indeed use a 12mm wrist pin and the exact same needle bearing as the new Phantom 85, so it can run most of those saw pistons.

I think the real question just comes down to how do I want to set this engine up. I kind of like the idea of having a lower RPM "chug-a-lug" tractor engine to contrast my Phantom. I think it would be interesting to have 2 engines of the same size with two completely different power curves.

My initial ideas are as follows.
Remove 2mm of that squish gap, pronto. Clean up and polish the combustion chamber and piston top. Both are quite rough textured.

Exhaust Timing - Aim for 80 BBDC/100 ATDC and 160 duration. I may pull that back a bit but that is kind of my generic figure for now.

Intake Timing - I am actually considering just leaving it alone and focusing on re-shaping the roof and floor to keep the flow even. This will probably add a bit more intake timing, which I would be ok with. I could probably add up to 10 degrees and still be ok. I would like to try and widen the port a hair as well. Also considering just running a windowed piston and reed. Neither are all that expensive, and are surprisingly off the shelf items.

Transfer Timing. - I hope that with removing the lips I can at least get the transfer duration to 110 degrees. A little more than that would be nice, but without the right tools to help maintain the roof angle it could prove problematic.

The above would give me 25 degrees of blowdown, which is a decent amount. This is why I may dial back the exhaust a couple of degrees and focus more on widening the port. That should aid flow while reducing the blowdown a bit.

This would all give the motor a funky combination of port timing and durations for the intake to be capable of slightly higher RPM. The blowdown also favors a higher peak RPM. The exhaust duration favoring slightly lower RPM, which somewhat cancels one another out. This is where being able to raise the transfer roof a bit would be really nice to try and bring that blowdown number down and transfer duration up. I think that would correct the biggest disparity in this engine in terms of power production (aside from the compression at least.

Oh, steel piston rings to go with the iron sleeve along with a proper cross hatch would probably be a good idea as well. I literally snapped both origina rings without even trying that hard. They were REALLY brittle and cheap. Thankfully, the MS380 piston I bought came with steel rings, and they are the exact same size.

I want to kind of aim this engine to have peak power around 5500-6500rpm and kind of lose steam around 7000-7500. I want and engine I can pull away at idle speed and it just goes. A "stump puller." This would also mean if I installed it on my bike to replace the Phantom, I would have a top speed of maybe 35-40mph, which wouldn't be bad. Trade speed I don't want for acceleration and climbing ability I do need. Sounds like a win.

I also think I am going to balance this crank as well. I may as well since I will have it apart. I think if I can make everything else flow well, the upper transfers having such low duration and hopefully make decent power.

Combine this engine with one of the longer header tube expansion chambers out there as well like the cheap MZ clones and I think I might just have a tractor engine on my hands.

This is meant to be an ongoing project thread to show the steps and work as I go, and to provide a good data source for any poor fool, or strange fool like me, that decided they like pain too. In all fairness, a 49mm big bore kit on a standard engine kit would probably make more power out of the box, and maybe the same power after I do all this work. The extra CC's are what I am after... all 9 of them lol.
I do welcome all opinions and suggestions on my thought process and plans, so feel free to chime in. Also open to possible suggestions for a right angle tool that takes dremel bits that might fit in there.
Yeah sounds good, I would be careful shaping any intake or exhaust ports. My name's Chris and I built a few in the last couple years and so far my yd 100 is one of the better cheap ones, but still produces some top numbers.
 
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