Newest Phantom 85 Information

[mony0_3]

If you want to use the other rings you could. If you were going to do that though get them without the caber rings and save some money. Also be aware that the pop-up piston will increase compression so if you were wanting to remove base gaskets it may make the compression higher than desired.

I am a fan of Caber rings personally for a number of reasons. They are just a higher grade of material. They are incredibly tough while also being flexible - aka proper heat treating. The edges have a slight chamfer to them so they don't snag ports as easily and they just last forever. They are probably one of the best names in the 2 stroke world when it comes to rings for a reason.

What dimension are you measuring?

I have an MS380 wrist pin needle bearing right here in my hand and it measures 16mm OD x 12mm ID x 13mm W

Here just to show some visual proof this is 3 pictures showing an 038 wrist pin bearing and pin in the end of the Phantom rod and with the 038 piston I have as well (click the picture for a larger view)

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[ImpulseRocket]

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then I am not sure what bearing they sent you but it isn't a proper 038 unit

 

[mony0_3]

then I am not sure what bearing they sent you but it isn't a proper 038 unit

That's why I used the stock bearing.

 

[noah9988]

Got my phantom this morning and got to play around with it a bit. First impression seemed good. Ports were a bit rough around the edges but nothing crazy. One of the first things I noticed is the weird shape of the intake port... it didn't match the gasket at all, which also didn't match the reed assembly. Got everything matched up, and all seemed well. Skip ahead to when I have the jug and piston on, and I notice that the window on the piston didn't line up exactly with the intake port. I didn't measure anything or take a close look to see if I could tell the the intake port is really off center or not, but I'll check it tomorrow. The exhaust port, gasket, and exhaust matched perfect. One thing that caught my eye is how low of a duration the exhaust port seems to be, compared to how I port my 66cc cylinders, I did raise it slightly.

Anyway, after some smoothing of the casting flaws, I put the jug on. Only, it wouldn't go all the way down. I tried pressing it on there but no go, didn't want to budge. So, I took the head nuts and tightened it down, forcing the cylinder down into place. After that I measured my squish with the meteor ms460 and was surprised that it was probably over 2mm. I couldn't get an exact reading because the solder I have is 1mm thick.

So, I decided to take the jug off and check with no base gaskets... only the jug was stuck on there. I had to take a hammer and hit the studs for the cylinder to come off. That was a bigger issue than I realized. I drilled out the stud holes in the cylinder a bit to try to get more clearance and it helped. After some more fiddling, I realized that I could put the cylinder all the way down, and the bottom of the cylinder will touch the base gasket toward the intake side, but there's a huge gap on the exhaust side. I'm really not sure what's causing this. It could be that the stud holes aren't drilled straight, idk.

After that I wanted to split the cases to surface the case part to make sure it's flat, but I couldn't get the nut off that holds the clutch basket on, and I don't have an impact gun. I'm going to put it together as it is, because I can get it to mate together after the nuts are torqued down I think. I also don't know why my squish is huge, but I'm not going to mess with it any more. I put the studs back in with loctite and I'm gonna send it.

Aside from that, a washer seems to be missing for one of the bolts that hold the reeds on, and I didn't get an o ring with the carb (or maybe I did, and just haven't found it yet). The gas tank is really nice. Paint is excellent, no rust or crap inside of it.

 

[ImpulseRocket]

Got my phantom this morning and got to play around with it a bit. First impression seemed good. Ports were a bit rough around the edges but nothing crazy. One of the first things I noticed is the weird shape of the intake port... it didn't match the gasket at all, which also didn't match the reed assembly. Got everything matched up, and all seemed well. Skip ahead to when I have the jug and piston on, and I notice that the window on the piston didn't line up exactly with the intake port. I didn't measure anything or take a close look to see if I could tell the the intake port is really off center or not, but I'll check it tomorrow. The exhaust port, gasket, and exhaust matched perfect. One thing that caught my eye is how low of a duration the exhaust port seems to be, compared to how I port my 66cc cylinders, I did raise it slightly.

Anyway, after some smoothing of the casting flaws, I put the jug on. Only, it wouldn't go all the way down. I tried pressing it on there but no go, didn't want to budge. So, I took the head nuts and tightened it down, forcing the cylinder down into place. After that I measured my squish with the meteor ms460 and was surprised that it was probably over 2mm. I couldn't get an exact reading because the solder I have is 1mm thick.

So, I decided to take the jug off and check with no base gaskets... only the jug was stuck on there. I had to take a hammer and hit the studs for the cylinder to come off. That was a bigger issue than I realized. I drilled out the stud holes in the cylinder a bit to try to get more clearance and it helped. After some more fiddling, I realized that I could put the cylinder all the way down, and the bottom of the cylinder will touch the base gasket toward the intake side, but there's a huge gap on the exhaust side. I'm really not sure what's causing this. It could be that the stud holes aren't drilled straight, idk.

After that I wanted to split the cases to surface the case part to make sure it's flat, but I couldn't get the nut off that holds the clutch basket on, and I don't have an impact gun. I'm going to put it together as it is, because I can get it to mate together after the nuts are torqued down I think. I also don't know why my squish is huge, but I'm not going to mess with it any more. I put the studs back in with loctite and I'm gonna send it.

Aside from that, a washer seems to be missing for one of the bolts that hold the reeds on, and I didn't get an o ring with the carb (or maybe I did, and just haven't found it yet). The gas tank is really nice. Paint is excellent, no rust or crap inside of it.

This is almost a play by play of some of my problems.

The intake port at the flange has always been funky. I can confirm for you (having had two different cylinders) that the port positions do vary from jug to jug. The port shape is definitely odd and I matched it all up with mine as well. I actually matched the gasket to the reed block and then matched the top of the reed block to the gasket and port on the jug where it is round and then filled in the bottom part a tiny bit and smoothed it out to get an even match at the bottom of the flange. I then marked out and opened up the port at the flange side of the jug and blended it into the rest of the intake port. I suspect they made the stock intake port smaller than it is on an MS460 to try and limit the power output some on the top end.

As far as the jug sticking. I too had that issue. The studs aren't aligned right because the case halves aren't aligned properly. I used a rat tail file to open mine up. You may notice that the intake is not actually in line with the cases and canted to one side. On my engine it points it to the left just slightly.

Part of the reason my squish gap may be smaller than some is because I did actually deck my cases to get an even mating surface for the jug. I don't have an exact figure to give since I didn't measure before hand but I probably took off .25mm. That being said I have noticed the squish gap measurements of others are also different. I can only assume there is some variance in the flange thickness on the jugs and/or differences on the case side of things.

The clutch basket nut on mine was also very tight. I actually cracked a socket on it trying to break it free.

 

[noah9988]

This is almost a play by play of some of my problems.

The intake port at the flange has always been funky. I can confirm for you (having had two different cylinders) that the port positions do vary from jug to jug. The port shape is definitely odd and I matched it all up with mine as well. I actually matched the gasket to the reed block and then matched the top of the reed block to the gasket and port on the jug where it is round and then filled in the bottom part a tiny bit and smoothed it out to get an even match at the bottom of the flange. I then marked out and opened up the port at the flange side of the jug and blended it into the rest of the intake port. I suspect they made the stock intake port smaller than it is on an MS460 to try and limit the power output some on the top end.

As far as the jug sticking. I too had that issue. The studs aren't aligned right because the case halves aren't aligned properly. I used a rat tail file to open mine up. You may notice that the intake is not actually in line with the cases and canted to one side. On my engine it points it to the left just slightly.

Part of the reason my squish gap may be smaller than some is because I did actually deck my cases to get an even mating surface for the jug. I don't have an exact figure to give since I didn't measure before hand but I probably took off .25mm. That being said I have noticed the squish gap measurements of others are also different. I can only assume there is some variance in the flange thickness on the jugs and/or differences on the case side of things.

The clutch basket nut on mine was also very tight. I actually cracked a socket on it trying to break it free.

That's some valuable information, thanks. My intake port must also be off to the left then. I noticed that it looks like they milled the case surface. I don't work today so I can finish building it and take some pictures.

 

[noah9988]

Here are some pictures. The intake is, in fact, really messed up. I don't think it will affect performance too much though. As you can also see, the jug doesn't sit flat on the case, although once I torqued the head nuts down it was fine, and it's not leaking.

 

[ImpulseRocket]

In the very first picture it looks like the case halves were not milled down all the way. The rear corner of the transfer area is really thin where the machined surface is. On mine it was completely flat even before I surfaced it.

Your jug not sitting flat is similar to the issue I had. That is why I had to use a rat tail file to elongate the stud holes a bit to allow it to seat fully.

As for the intake port. If you are looking at the inner part being off to one side and thinking that is bad it isn't. That is how MS460 saw intake ports are shaped. I meant the literal reed block and carb being canted off to one side because the jug wasn't sqaure with the cases.

 

[noah9988]

In the very first picture it looks like the case halves were not milled down all the way. The rear corner of the transfer area is really thin where the machined surface is. On mine it was completely flat even before I surfaced it.

Your jug not sitting flat is similar to the issue I had. That is why I had to use a rat tail file to elongate the stud holes a bit to allow it to seat fully.

As for the intake port. If you are looking at the inner part being off to one side and thinking that is bad it isn't. That is how MS460 saw intake ports are shaped. I meant the literal reed block and carb being canted off to one side because the jug wasn't sqaure with the cases.

Yeah I saw that the machined area was funny looking. I did end up making the stud holes bigger.

Good to know about the intake.

 

[noah9988]

Welp, sad to say that it blew up (twice). I'm not sure what caused it, but the lower piston ring snagged the exhaust port. It happened at idle, and the engine locked up. I took it apart and found what I thought to be minimal damage. Only the lower piston ring had any damage, it was severed and a chunk of it was lodged in the ring land. After some inspection and clean up, I believed that I salvaged the piston and cylinder. Like I said, I didn't see major damage. I made sure to chamfer and sand the exhaust port again. I used the stock rings this time, and wouldn't you know it, the ring snagged again almost immediately. Same failure, only the lower ring got damaged, but this time I saw that a chunk of the cylinder came off and there is a deep gouge above the exhaust port. The pictures are from the second blow up.