Zenoah uses the HDA 48 on the G-45 and G-62. 15mm

It is 47.2.

A friend of mine has 3 echo twin cases for sale.

If interested please PM me.

What are they going for now days?

Sent you another PM.

Sent you a PM a few days ago. Does your friend still have the cases?................m

My Giant Stik "died"....

Ran out of fuel and hit a telephone wire trying to make it back to the field.

The engine wasn't hurt.

AV8TOR

But then I fixed it....

While I was at it, I decided to work on the BME twin. I didn't do any mods when I built the engine; I just assembled it stock. I decided to see what could be done to improve it.

I found that Keith had designed the block so that the cylinder sat lower, and therefore the squish area, at least on my engine, was fine with a normal gasket at the cylinder base. However, this causes a problem. The piston never uncovers the exhaust port completely. Also, once again at least on mine, the exhaust timing was a very low 122 degrees. I chamfered the edge of the piston at the port to allow the port to open completely. This also raised the timing somewhat, but not enough. So I raised the exhaust port until I got 150 degrees exhaust timing. I then assembled the engine, and installed a 15mm venturi carb in place of the 13.5 I had been running.

Wow, what a difference!! It had been turning an APC 18 x 8 at 8000 rpms. Now it turns the same prop at 8700. That is a really big power gain. I don't have a 19 or 20 x 8 to try, but when I get one I'll let you know the rpms on that. My other twin that I have been (slowly) working on uses 25cc crankshafts, and doesn't have the problem with the piston not opening the exhaust port completely, but you have to make spacers to raise the cylinders to accomodate the longer stroke. It will be interesting to see how that one runs....

AV8TOR

Bad for the plane but good to hear about the engine coming through.
Cool,great news on the engine.Ill check mine after its assembled.On mine im starting on making a reed block that i will be attaching the red valve setup from the Poulan 33cc saw.It uses one Stainless reed shaped like a teardrop.
The reason im trying this is because i have 3 of them and there easy to come buy.Actually,i need to change that.I have 2 from poulan and one from the 31cc craftsman weedie with the carb mounted on the bottom of case.The craftsman is the creme colored on on top left.
The reed mesures 1" on bottom-1/2"on top-1-1/4 long.
The reason for the aluminum plate beneath the G-10 plate is for the carb reed box to bolt to.The G-10 is for a heat dam.
Heres a pic so far of all the parts im doing.The block will have a dimple cut with an end mill [or drill bit] so the screw that holds the reed on cant fall in the case if it comes loose.
I will make the reeds teardrop shape in the case or just make an oblong hole,or just a square.Whatevers easier.Still trying to find 2 shortblocks of the 22 or 24cc.

Hello guys and Help, I finally obtained a BME twin crankcase after looking for some time. I have two new Echo 23.6 crankshafts with left hand threads so one would need a stud installed for the prop. Then I need to have the shafts machined and welded. The cylinders, pistons and rods are also new, so it should make an excellent little engine for the Ziroli DR1 I am working on. If anyone reading this post is capable, has the time, and is willing to take on the job let me know and we will try to work out something to get this done.

Thanks George

I welded 2 of my cranks so far.Ill email a friend i know that just did his and see if he wants to tackle it.Ill have him get in touch with ya or ill get back.Look up echo left hand threads in this forum.Av8tor did a left hand crank conversion where he drilled out the crankshaft and left a very detailed instructions that you could follow.If you have the equipment.If not let me know and i could do it.

Morning Buck, What you posted sounds like what I need. I have a prop adapter designed to work on the left hand thread Echo crank, but it may be too small to work on a 48cc. It was made for the 23.6 engine. My problem with it is that the Adapter and prop washer are small, you would have to see it to know if it could be used or not. I do not have the machinery or the skills to use them and don't know any one who does. If you hear any thing from your friend or you can take it on , let me hear more from you.

Later george

Whats the diameter of the face of the hub that the prop seats against.
You could use that hub,use locktite,then you could also use setscrews as long as the hub slides over the crank past the threads about a 1/2 inch or so.
The first crank i welded is ok but i wouldnt sell it to anybody.And i sure wouldnt charge anybody.Like i said,it was my first crank.Its just a hair off in my lathe but i think it would work.This is not for my BME twin.Its for another project i was trying but i might just drop the project anyway.

Buck, This is a two piece hub. The dia. of the adapter that mates to the prop is 1.20". I took some pictures of it and posted them on the Echo 2400T post. Post # 133. It was made by Roy Sholl. I didn't keep the disk I recorded it on, I usually format and reuse them. If you want to search you can see how it is made. It really looks good I was just concerned about the Surface area against the prop.

Later George

What i would do is take the hub and put it up against the back of an APC prop and see where the hub sits or how much the prop overhangs the hub.
Anything above 40cc i usally like my face about 1-3/8.But im usally running wood props wich have a larger diameter center.APC and some zingers are smaller.
The center portion of my 17x8 APC is 1-1/4 in diameter.
I also looked at my BME 21x10 and checked the back of it to see the marks left from when it was mounted on my G45 and the marks are only 1-1/2.This was a stock G45.
So i think that youd be OK.But if you want i could make you one.I could make it the same way but theres no point if your only going to gain 1/8 to 1/4 of an inch.
And theres no sense in making a huge hub with excess sticking out from behind the prop.
Ill send a PM to av8tor or yu could and see what size hub his is and i dont remember what prop hes runnning.Hes starting a second one.
I went and looked at the one in that thread.

Off the present subject, but related. There is an Echo CS-610 twin cylinder saw up for bids (you know where) if anyone is interested in a project. The item is #330311573092.

Already doing one right now.Its just about completed.Just need to put the ign on and do a couple things to the carb.Im sure someone will go there since you posted it.

Sent ya another PM Ralph.

Hi..... Answering your PM on 3-15-09. My block is apparently the older squared off type (see post #326) . I have some reed parts ordered, listed on post #44 of this thread. Maybe they can be made to fit my block. I will send you more info by PM.

Later George

Heres a pic of my 61cc echo twin and you can see how the reeds are setup.
Notice the intake manifold is facing,thats how it bolts onto the case and it matches the BME shape of the case.The bolt pattern is exact also.
The only way for the parts that you ordered for the style that was posted on this thread is to make a new adaptor that your parts will fit to.We have the older case.This could be made from aluminum if your block from the homelite is G10 or similier.It would have to be thick enough so the pyrimid doesnt hit the journals on crank.
I am going to call [dandb] and see if they will sell me a set for the 61cc.If its the same pattern.
The other thing to do wich i might is to use 2 petals from the 33 saws as pictured above and screw them to a homemade block.In other words make my own 2 petal desighn reed block.
I do have a reed block coming from a stihl 33cc wich will work easy but i dont know if its big enough.Or ill just use a bigger carb.Ill post a pic when it arrives.

GaaauuullDarnnnnnit.Forgot the pic again.First the gray[silver]hair and now this.Crap!

Hi..... I like the way that reed assembly lays over to the side of the engine rather than straight up with the Homelite reed set-up. Keep us informed as to what you find out.

I didn't know that the older, square blocks were so different in the reed valve mount. The reed that the newer crankcase uses is like the one I sent you the link for Buck.

AV8TOR

Thats what i was trying to say but i decided that pics are better.The reason i think BME changed was echo discontinued the 61 twin around 84-85.Thats when bme started to use the newer case with the homelite.I cant tell but the 61 reeds should be larger.Oldtimer has a set ordered for the 61 and is going to give me the info.
Has anybody heard from ralph,ive been PMing and posting here but no response from him.

OK,heres what i did tonight after dinner.I recieved my reed from the stihl chain sawO19.There about 15-20 dollars.No problem getting.
The parts are going on in order from left to right.
The aluminum plate im using is to bolt one of the reed block screws to it and the other bolt will go through both plates and into the corner of the BME case.
The G10 board is my heat dam.
You can also see i recessed where the screw that holds the reed plate on is counter sunk so if it ever comes loose it cant come out at all and fall into engine.
The reason the aluminum plate has the honeycomb holes in it is also to keep stuff from going internally to the engine.I also thought,maybe,it might act as a gas.air seperator.Meaning that the fuel droplets might hit this and become smaller as more of a mist and be a better mixture.
Now im not sure if this will also cause some puddling.
I am using a WT-414,13.49mm.Also this carb has the long throttle and choke rods for easy hookup with a nose gear steering rod.Im going to go take a few more pics of the carb and post a link to the description of this high speed circuit.