xyz cdi
#5
I wonder how JB Weld would work. Place the pick-up in place...add a blob of JB Weld then use a worm gear clamp to hold evertning in place. The JB Weld should keep the sensor from moving much with a hose type clamp. Just a idea!! Capt,n
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From: linden, TN
solder or jb weld i didnt think of that I contacted a guy on e-bay that makes prop hubs and spacer rings for ryobi the spacer rings come with the magnet his work is top notch. I have ordered from him and he has good prices to I guess I will just have to wait untill monday to order that xyz unit from hobbyking and see how much weight i can save and to see if it works out thanks michael
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From: NEW BOSTON,
TX
I tried to epoxy my sensor to a hose clamp but it would not stay. The heat from the engine would eventually melt the epoxy. What I ended up doing was to drill holes in the clamp for a 2-56 screw. I then put the screws through the hole and held them in place with nuts while I ground off the heads of the screws with a dremel. Dont grind it all the way off but leave about a 32nd of the head left. Do this before mounting the sensor as the heat from grinding will melt the sensor. Found that out the hard way. After the heads are ground off, I removed the nuts and added a drop or two of CA to the screw to hold it in place. I now have a mechanical bond with which to mount the sensor. Works very well and it is possible to remove the sensor later if needed.
Also, I agree with going with the RcExl ignition. It is much better quality in my opinion. I have had both and one of my XYZ ignitions has failed. I would recommend Southeastrcengines.com. They have both and they are the same price. Shipped to your door with the sensor about $51.00 and you have a US distributor to back up the warranty.
Jim
Also, I agree with going with the RcExl ignition. It is much better quality in my opinion. I have had both and one of my XYZ ignitions has failed. I would recommend Southeastrcengines.com. They have both and they are the same price. Shipped to your door with the sensor about $51.00 and you have a US distributor to back up the warranty.
Jim
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From: Picayune,
MS
Michael do you have an address or contact info for the guy on e-bay that makes the rings with magnet installed. I am interested in converting a Hommie 30cc to cdi. Thanks for the info.
big Al
big Al
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From: linden, TN
big al the guys name is topcat on 5-2-2009 and he said it would a about a week before he would list them on e-bay he has to make them his work is real good and cheap price now he is some for a ryboi 31cc dont know if they will fit a 30cc but you can pm him and ask michael
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From: linden, TN
big al the guys name is topcat contacted him on 5-2-2009 and he said it would a about a week before he would list them on e-bay he has to make them his work is real good and cheap price now he is some for a ryboi 31cc dont know if they will fit a 30cc but you can pm him and ask michael
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From: linden, TN
Well I got my xyz ignition today and I set it up using the instructions from ch, I had a problem with it sucking gas to the carb even with the choke closed I just keep on flipping and it would bearlystart to draw the fuel so igotout the starter and boy did it fire up quick. When I went toadjust the carb it quit.I figured I lost the ignition unit wrong the magnet can out guess I didnt have it glued in good. So I put another magnet in and jb welded it and ping it around the magnet I am using a 4.8 volt battery pack on it I will try tommrow to start it and adjust the carb michael
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From: linden, TN
Well after I took the carb off there was a bunchof crap in the inlet screen so I rebuilt the carb and now it sucks fuel quickto the carb starts fairlyeasy using the starter I am going to fly it tommrow and I will tacit then transion is good so we shall see michael
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From: springfield, MO
How is this engine set up? Is it bone stock?
The key to ryobi performane seems to be
1. As good of a ring to cylinder seal as you can get. How much ring gap do you have? one ring two rings? what is the cylinder condition. May i suggest building a leak down testor to test this. It is the only way you know for sure what you have for a seal.
2. get as much of a compression ratio as possible. This is acomplished by reducing cylinder base gasket thickness or removing it altogether. if you do this make sure you measure as some engines will hit piston to head is you take it out completley. mine would hit so i used a .010 thick gasket instead of the .030 thick gasket. Power gain from this isnt extreme but should yeild 80 - 100 rpm.
3. As free flowing muffler as possible. An expensive aftermarket muffler isnt neccasary although they look nice and are much lighter. many guys on here have had good luck gutting out a stock one and welding in a half inch emt tube for the outlet and this will be more than adequate.
4. A much larger than stock carburetor. the stock carb venturi is about 7.5 mm. you want one that is 11.1 to 12.7 mm.
These from the testing I have done seem to be THEmost important factors in getting this engine to run good. I have tried many of the other mods suggested and have no power gain yeild from them when done on a test bench.
Depending on what cylinder you have you may benifit from increasing the exhaust port timming to about 105 degrees. the cylinders that seem to benifit fron this mod is the newer style cylinder with two transfer ports per side.
Also how did you set up your ignition. Did you use a degree wheel? did you make sure you had tru tdc set on your degree wheel?
The key to ryobi performane seems to be
1. As good of a ring to cylinder seal as you can get. How much ring gap do you have? one ring two rings? what is the cylinder condition. May i suggest building a leak down testor to test this. It is the only way you know for sure what you have for a seal.
2. get as much of a compression ratio as possible. This is acomplished by reducing cylinder base gasket thickness or removing it altogether. if you do this make sure you measure as some engines will hit piston to head is you take it out completley. mine would hit so i used a .010 thick gasket instead of the .030 thick gasket. Power gain from this isnt extreme but should yeild 80 - 100 rpm.
3. As free flowing muffler as possible. An expensive aftermarket muffler isnt neccasary although they look nice and are much lighter. many guys on here have had good luck gutting out a stock one and welding in a half inch emt tube for the outlet and this will be more than adequate.
4. A much larger than stock carburetor. the stock carb venturi is about 7.5 mm. you want one that is 11.1 to 12.7 mm.
These from the testing I have done seem to be THEmost important factors in getting this engine to run good. I have tried many of the other mods suggested and have no power gain yeild from them when done on a test bench.
Depending on what cylinder you have you may benifit from increasing the exhaust port timming to about 105 degrees. the cylinders that seem to benifit fron this mod is the newer style cylinder with two transfer ports per side.
Also how did you set up your ignition. Did you use a degree wheel? did you make sure you had tru tdc set on your degree wheel?
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From: linden, TN
Hi I did use a degree wheel and have it set a 30 degrees dtdc.As far as the piston it is a two ring and i am going to order a new piston and also get another wt 499 carb and see if it brings up the rpm.Now on my gas to glow ryobi with a new piston and carb it will tac at 7400 rpm. What plugdoyou all use for the xyz i am using a chapion rd7j gapped at 20. does that sound about right? michael
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From: springfield, MO
Hi I did use a degree wheel and have it set a 30 degrees dtdc.
30 degrees seems a bit high. i would try 28 degrees. so there is a 2 degree diff right there and if your 4 degree off on your wheel theres 6 degrees
As far as the piston it is a two ring and i am going to order a new piston
I use the same plug as the stock ignition.
The wt 499 is a 11.11 mm venturi size. http://web.archive.org/web/200505220...rtnum=WT-499-1
I have run a 12.7 mm venturi with good result.
You say get another wt-499 is that is what is on it now?
Tha another darn ryobi post has good info on the leakdown procedure page 12 post 291 and 292, page 13 post 305
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From: linden, TN
ive read that post the degree wheel i used was from ch ignitions and i used your part about the dial indcator to find true tdc as far as the wt 499 it is suppose to be compatible with methonal. If I cant get the rpm up toabout 7000 withe cdi and new piston and rings and carb I will change it over to gas to glow my other gas to glow is tacking 7400 rpm with a new piston and ring and a wt 499 carbI have had the engine running and tried to adjust the halls sensor but the engine quits when i try to adjust it should i try to reset the timming to 28 deg and see what the rpm is by the way it is a stock carb the prop is a mas 18/8 michael
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From: springfield, MO
Theres no reason why you shouldnt be able to get those numbers. I am getting 7400 on a pretty much stock engine with free flowing muffler and 12.7 mm venturi. i am using the xyz ignition set at 28 deg. i got the best ring seal i can get with a good cylinder and two ring piston. and i moved the cylinder down .020 to up compression and thats about it really.
What is you cylinder? does it have the two runner per side transfer ports or the one runner per side?
ditch the stock carb for sure, there just to puny. that will make i big diff right there. what about muffler??? what are you using there?
What is you cylinder? does it have the two runner per side transfer ports or the one runner per side?
by the way it is a stock carb the prop is a mas 18/8 michael
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From: linden, TN
the cylinder has the two slots down the sides and i have replaced the gaskets with thinner ones i will try to readjust the timming on it my pointer might be off but even with a stock carb it should get better then 6400 rpm michael
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From: springfield, MO
the cylinder has the two slots down the sides
i have replaced the gaskets with thinner ones
i will try to readjust the timming on it my pointer might be off but even with a stock carb it should get better then 6400 rpm michael
If you lower the cylinder as far as you can go, install the larger carb, make sure your muffler is free flowing and that should get you to 7000 rpm. It might not though till you do the timming mod.
Also what does your cylinder look like? does it have any scores in the cylinder at all???
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From: linden, TN
the cylinder has no score marks on it and the muffler is the stock muffler gutted and holes drilled in it I will have to get a bigger carb and see how that goes also it has a miss in it now and then i think it is the spark plug have to chang it out and see michael
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From: springfield, MO
Sounds to me like your numbers are pretty much in line with what they should be on that size a prop. Sounds like your on the right track. change the carb out and let us know how it goes. post your results on the another darn ryobi post so it can add to the testing base there. as far as a slight miss now and then it could be your spark plug and it could also be the carb as these engines seem to be real mixture sensative.



