The LD110 Adventures.

ImpulseRocket89

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(Part 1) So, if it isn't abundantly clear that I am a bit weird and love a challenge, now it should be. I chose my Phantom in part because it had a bad reputation, so when I found out about the 110cc and it's unbelievably crappy performance, I just had to get one! Resistance was futile.

First of all. My Phantom was filled with metal shavings. This engine is just filled with metal dust. Fine dust. It's in and on EVERYTHING. So another tear down here I go. Also, the crank is not as surprisingly untrue lol.

So before I get into a slightly lengthy talk and a good number of pictures, let's go over some numbers.

Squish Gap - 2.77mm. Not even joking. If you remove the nearly 1mm thick head gasket made out of not at all soft aluminum, that actually drops it down to a slightly less turdtastic 1.86mm. Yeah, both the head and jug need quite a bit of material removed. I also need to figure out a head gasket solution. I know the soda can method can work, but I would like something a tad thicker and a bit softer. I'll figure something out.

Port Timing. (My figures aren't the most precise ever due to my degree wheel being annoying, so don't nitpick please).

Intake - Opens 62 BTDC/118 ATDC and 124 Duration. Exhaust - Opens 68 BBDC/112 ATDC and 136 Duration. Transfers - Right Side 53 BBDC/127 ATDC, 106 duration. Left Side 51 BBDC/ 129 ATDC, 102 duration.
Blowdown - Right side 15 degrees. Left Side 17 degrees.

I seriously wonder if this engine would even make much beyond 1 horsepower... if it even would run at all. Not even a slight exaggeration.

Let's explore those ports now so we can get a real understanding of just way it's so bad.

Honestly, the intake timing really isn't the worst ever. It's the iron sleeve protruding from the roof of the port and on the right side that will cause the most issues. The side can be opened up for sure and the port floor could be dropped some and widened, so it isn't all doom and gloom. The roof portion is a huge turbulence maker though, and I may just have to whip out the JB Weld to try and fill that area in and smooth it out. I don't want to remove the lip at all though because it actually sits flush with the bottom of the piston skirt and covers the top ring at BDC perfectly, so it has that going for it. These two pictures show TDC and BDC.




Unfortunately, this is the best of the ports on this whole engine. The exhaust is the worst, or tied with the transfers. Not only does the piston go down all the way to be flush with the exhaust port floor, and actually sticks up about 6mm), but the sleeve is also blocking about 4mm of the top of the exhaust port and a couple, again, on the right side as well. Just removing that iron lip would probably add 5 or 6 degrees of exhaust timing all on its own.

 

ImpulseRocket89

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(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.
 

DAMIEN1307

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DieselTech

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(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.
Is this thing actually called a LD110 or is it just a CDH110 engine. Or is this some new iteration of a 2 stroke CG. I have a CDH110 new in the box I've never done anything with. I bought with the intentions of making a case reed CG engine. The biggest fail I see is the cylinder head design on my CDH110 engine.
 

ImpulseRocket89

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That would be nice, but nobody makes anything for this engine. It has a 60mm stud spacing. The only ones that exist are the same as the one it comes with.
Is this thing actually called a LD110 or is it just a CDH110 engine. Or is this some new iteration of a 2 stroke CG. I have a CDH110 new in the box I've never done anything with. I bought with the intentions of making a case reed CG engine. The biggest fail I see is the cylinder head design on my CDH110 engine.
To be honest I don't know what to call it. I didn't buy my engine from CDH, but that doesn't mean it isn't their engine either. I have just seen a few others called it an LD110, so that is the name I gave it. Probably the exact same as the CDH110 you have.
 

DAMIEN1307

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That would be nice, but nobody makes anything for this engine. It has a 60mm stud spacing. The only ones that exist are the same as the one it comes with.
Wrench is on vacation right now until the 15th but he makes his own head gaskets and I know you already know how to do things so this might work for you as well....You can use your existing one as a template.




 

ImpulseRocket89

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Wrench is on vacation right now until the 15th but he makes his own head gaskets and I know you already know how to do things so this might work for you as well....You can use your existing one as a template.





Yeah, my plan was to make my own gasket. I can get T6 down to .016" thick. Or a sheet of 5052 H32 .02" thick, which while a bit thicker, is a lot softer and would make a better gasket. I don't want a head gasket thicker than about half a mm, and I try to avoid using copper with aluminum cylinders and heads due to the galvanic corrosion.
 
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