RE: another darn ryobi post (ryobi performance modification, analysis and comparison)
yeah, it still is stamped as such but it's an I beam style vs sort of an oval type like earlier models.
Posted on: 4/21/2010 9:05 AM by Author "Elnino" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=9677622

RE: another darn ryobi post (ryobi performance modification, analysis and comparison)
Mine was in a hybrid type. It still had a bolt on fan shroud but used twin piston rings with the slits in the cylinder. It was by MTD (who made these Ryobi engines). I would suspect than any newer ryobi type would have the newer type rod. See this link for the newer piston/rod - [image]http://www.ereplacementparts.com/images/part_753-04367-1.gif[/image] From: http://www.ereplacementparts.com/piston-and-rod-assembly-p-282359.html
Posted on: 4/21/2010 12:43 AM by Author "Elnino" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=9677159

RE: another darn ryobi post (ryobi performance modification, analysis and comparison)
Well so far i have not heard of any problems with the newer rod exploding. Perhaps it just needs more time but my engine is at least a testament that the newer ones are much stronger.
Posted on: 4/20/2010 11:03 PM by Author "Elnino" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=9676910

RE: another darn ryobi post (ryobi performance modification, analysis and comparison)
[quote]ORIGINAL: Rcpilot I blew one up.[/quote] Was that one with revised 'I beam' style con-rod or the original pressed type? Assuming it was the rod that let go as that seems to be the weak point. I am running the newer type and run in excess of 12k in my boat...
Posted on: 4/20/2010 6:40 PM by Author "Elnino" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=9676213

RE: another darn ryobi post (ryobi performance modification, analysis and comparison)
hehe, Prather 280 - It's in a boat....
Posted on: 1/26/2010 7:49 PM by Author "Elnino" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=9450893

RE: another darn ryobi post (ryobi performance modification, analysis and comparison)
My ryobi does well over 8000 RPM and i have not thrown a rod yet (touch wood) but my engine is the newer type with 'I' beam style rod and twin piston rings, not the older style.
Posted on: 1/26/2010 5:51 PM by Author "Elnino" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=9450534

RE: another darn ryobi post (ryobi performance modification, analysis and comparison)
[quote]ORIGINAL: moparcolt I am running a WALBRO WT 29A carb right now I am not sure of its size. Chris [/quote] The number stamped on the venturi is the size of the carb in 64ths of an inch - i.e 32/64ths = 1/2"
Posted on: 11/29/2009 7:47 PM by Author "Elnino" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=9290310

RE: another darn ryobi post (ryobi performance modification, analysis and comparison)
While it's getting a little OT i'll add my experiences with octane and ethanol: Ethanol is ok apart from the fact that it tends to harden the fuel pump diaphragm in the carb. However, if you replace it with the teflon (brownish colour) item in a walbro gasket kit, you should not have any problems. In my part of the world, the higher octane fuels are not JUST higher octane, they also have a higher energy rating meaning higher octane for me IS worth it. I see a significant improvement in power when using premium fuel. Stick to getting your fuel fresh from a station that has high turnover. Fuel is not meant to last more than a month or so and most of the 'volatiles' evaporate off quickly. For my (rc) boat, i only buy,mix and use on the day. I do not store fuel at all anymore. Once I had some old fuel but unmixed in a sealed container for 2 months. When i used that, the boat would just not run right - fresh fuel and it was back up to pace.
Posted on: 11/29/2009 5:01 PM by Author "Elnino" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=9289885

RE: another darn ryobi post (ryobi performance modification, analysis and comparison)
[quote]ORIGINAL: moparcolt I also have one more carb to try it is a big one, has a 32 stamped in the venturi, we'll see if it helps or hurts! chris [/quote] All walbro carbs are measured in 64ths of an inch - Meaning a 32 is a 1/2" carb. This is an easy way to tell how big they are when you're sifting through the second hand ones at your local repair shop.... By the information here, i don't think there will be much difference in performance but i run a 32 fine in my boat, i.e it won't hurt it. Also, i have heard of some people removing some material from the butterfly around the idle jets on the bigger carbs. They make the crescent bigger (about 2mm deep). Apparently this greatly improves idle performance and it also means you can get better needle settings for a full rev range rather than tuning for idle.
Posted on: 11/26/2009 5:18 PM by Author "Elnino" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=9283171

RE: another darn ryobi post (ryobi performance modification, analysis and comparison)
diceco, I don't have specifics on me right now but the pipe i have was based on a design created with javapipe (http://www.mh-aerotools.de/airfoils/javapipe_en.htm) using port area and timings that i determined from the engine at the time. RPM was based on about 8K i think but it's doing more than that now. Un-silenced it really annoys the neighbors but there is no reason you could not incorporate a silencer on the end. Mine is very thin and pretty light, i fabbed the main pipe from an old stainless steel heater flue i had out the back using a mig welder and lots of tack welds. The heavy part is the header from the engine to the pipe. I tried thinner stuff but it cracked from vibration (although that was before i balanced the flywheel properly). My biggest problem is heat on the coupling between the header and the pipe. I'm yet to find something that will hold up to the heat. Does it make a difference? Well I'm not sure! Perhaps i will stick a can back on it and give it a shot - i have plenty of them... BTW, I had heaps of problems with the bolts stripping out on my engine so i used helicoils on the exhaust, head and carb manifold. Now it is really strong and i can use quality stainless bolts... I'll take some measurements of the pipe tonight and post back.
Posted on: 11/11/2009 10:27 PM by Author "Elnino" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=9247516

RE: another darn ryobi post (ryobi performance modification, analysis and comparison)
I wonder if that is the 'older' style rods though? I have been using the newer one for a long time and never had a problem. I only ran for a short time on the old style rod. It would be interesting to see if any of the newer I beam style rods have exploded. I guess the difference for me is if the rod does let go, my boat just stops and i fish it out. If a rod goes in your plane, it's a totally different story! If i do ever happen to have it let go on me i'll let you know here but i'd say with the RPM's i'm pulling you're pretty safe going higher on the new style rod. Although i've probably jinxed myself now.... i have also heard of the crank flexing and causing interference with the head in these (being that they are only a half crank engine). I am yet to see any evidence of this. The next engine i am close to having a go with is one from a Pope brand Blower vac. 26cc cross flow, full crank, pull start and at AU$87 from the local department store it's a reasonable option for a cheap boat. The only thing that puts me off is that it is a slant plug style so it is harder to water cool. Next to useless for a plane though. If i build up another boat, i might give one a shot.
Posted on: 11/7/2009 9:40 PM by Author "Elnino" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=9236524

RE: another darn ryobi post (ryobi performance modification, analysis and comparison)
apologies for digging up a somewhat 'old' thread but i just couldn't resist a reply. Kudos to all the research (and blood) that you guys have put in to all this. I have just read all 20 pages and i'm so glad i did. I can not believe that i didn't come accross this page AGES ago! Although not a direct comparison, i have a modded/hybrid Ryobi in my BOAT! I came accross this thread looking for some ways to get more power from my rig but as it turns out, i have done most of them already! I have gone through almost all of these mods on mine and just by chance ended up with a similar combination- An Old style crank/case with old head and the newer MTD style twin ring piston with a Walbro WT-257 (1/2") as it gave me the best performance. I am also running mine with a large tuned pipe and velocity stack and it SINGS! I don't have figures (sorry) but listen to it in the video below, it is pulling some huge RPM (est . 12k) and i have never had any problems with mechanical failure, i.e rod etc. Mine uses the I beam style rod. The head is modified for water cooling/boat use, the flywheel is machined down and i use a pulley and electric motor to start it. I think there is still some more potential for the engine in my setup but what i find baffling is there has not been too much talk of what fuels/lubricants have been run in them when the tests were performed - this can easily affect stats between the engines. I run mine on 98 octane premuim fuel (not just high octane, it has more power units per cc) mixed with Castrol Racing TT fully syn oil at 20:1. I have not seen any evidence that running it at lower concentrations of oil makes it run faster and running more oil at these RPM's has to be better. I have NO carbon build up with hours and hours of running. The internals of the engine are like new. Not even any tanning and only what i would call normal wear. The crank bearings however seem to suffer. I suspect that is more because of the occasional water ingestion rather than the speed/forces they endure. I have also noticed for those that have the entire new engine style (with compression relief, 2 rings etc) that the area around the crank where the ports start, on all of mine there are some fairly reasonable casting marks causing an edge on them. Older ones do not seem to have this. I would suspect that removing them with a file/dremel would make a measurable difference with the flow past them. Check these: [youtube]http://www.youtube.com/watch?v=IBM6XZyVhMg[/youtube] [image]http://www.hux.net.au/wp-content/uploads/2008/10/pa160388_sml-300x224.jpg[/image] [image]http://www.hux.net.au/wp-content/uploads/2008/01/engine_small.JPG[/image] I have many more pics if anyone is interested. Long live the ryobi!
Posted on: 11/6/2009 9:41 PM by Author "Elnino" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=9234077

RE: Spektrum SR300 antenna mod?
Too little to late probably as most boaters would be using FASST. But here's hoping that it's just a different RX.... I did happen to browse the site last night and noticed that they now have 'carbon shell' compatible RX's for the air radios so hopefully this will carry on to boats.
Posted on: 4/14/2009 6:26 PM by Author "Elnino" in the forum "RC Boats General Discussion"
http://www.rcuniverse.com/forum/fb.asp?m=8681476

RE: Spektrum SR300 antenna mod?
Well, i done some range testing using my drifter. So far, i have not been able to go far enough to get it to drop out. I was running it at around 150m away from me and still not a problem at all. I even deliberately held the tx so the antenna was at right angles to the one in the car so it was incorrect polarity and it still worked fine at that distance. For those not in the know, an antenna mounted in the wrong polarity can mean a signal loss of 20+db which is a significant reduction in signal. i couldn't test further than this just yet because i lose sight of the car. I need to get someone to walk away with it and keep an eye on the light in the RX. So, in summary, so far i have very positive results. If this continues in the boat i will be extremely happy!
Posted on: 4/14/2009 5:52 AM by Author "Elnino" in the forum "RC Boats General Discussion"
http://www.rcuniverse.com/forum/fb.asp?m=8679668

RE: Spektrum SR300 antenna mod?
Wasn't Spektrum's first release a 2ch surface?? I thought their air models came in later? I wasn't in to Air back then but that's what i thought. I know the whole spektrum in boats thing has been thrashed to death here but I'll continue my research and i'm hoping to come up with somewhat of a reasonable solution. I agree that for some reason Spektrum air radios seem to work ok on water compared to surface items. I thought this might be because of DSM2 but the DX3R is DSM2 and still seems to suffer the same fate. Stronger signal? More ECC? Not sure. I read somewhere that because FASST changes channel, it doesn't see the reflections but that still does not make sense because it 'only' changes every 2ms. RF travels at the speed of light so in 2ms it would cover ~6000km So unless you are getting the reflections from over 6000km away, that is not the case. What i DO believe is that the RX has much better error checking and filtering of the signal so that it can see through these supposed reflections. Based on that, one would possibly think that Spektrum could release an RX specifically designed for water use that has more signal filtering and verification. Then they could make it a special water proof model too! Maybe even just a software update to existing RX's! I really think Spektrum have let us boaters down. There has been plenty of time for them to come up with a solution that is consistant and reliable meaning that they are losing mass business to a rival company. I have a DX7 for my Heli's and planes and i love it to bits. Never a glitch, never a range issue - nothing! Same with the DX3s on land, range beyond my vision and rock solid, I just hope that i can continue this on water too. Oh and FWIW, I am a Network engineer (Read: Computer Geek). I run several long range 2.4ghz wireless network links over 5+km and not one of them is affected in any shape or form by fog/rain/hail etc. NO degradation in signal strength whatsoever regardless of the water in the air.
Posted on: 4/7/2009 7:29 PM by Author "Elnino" in the forum "RC Boats General Discussion"
http://www.rcuniverse.com/forum/fb.asp?m=8659028

RE: Spektrum SR300 antenna mod?
Ok, i've done it!! See the pics. It's pretty self explanatory but basically i have removed the UFL connector from a wireless card in a busted wireless access point, soldered it to the board and hey presto! Procedure: Step 1 - Grab the RX and undo the four screws holding the 2 shells together Step 2 - Using a hobby knife or similar, gently scrape the CA glue from the base of the stock antenna. Take your time, do it a little bit at a time. Remove the old antenna by 'tinning' the solder point on the bottom with more solder, then the antenna will pull free. You need to add solder as these are RoHS boards which means the solder does not contain lead and is a pain to de-solder. By adding some, it melts easy. Step 3 - I'm not sure if this is really needed but i did it to make sure there was no shorts in the connector. Using hobby knife again, scratch the area under the UFL connector where the center pin conductor goes. Step 4 - Scrape the green copper covering off where the ground pads go and then tin them very lightly Step 5 - Place the UFL connector and reflow the solder to the 2 ground points then the signal connector. Step 6 - Connect new antenna to board. You'll need to cut a slit in the side of the case for the coax to exit All done. I have put the RX in my drifter for testing for the moment, range seems good so far but i have not been able to do a full range check just yet. Once the range is tested (and we get some rain) i'll try it in the boat. I have 3 of these antennas of varying lenghts, the longest being almost 25cm long and that will go on the boat. I'll update this thread as i do further testing....
Posted on: 4/7/2009 6:42 AM by Author "Elnino" in the forum "RC Boats General Discussion"
http://www.rcuniverse.com/forum/fb.asp?m=8657072

RE: Spektrum SR300 antenna mod?
Great to hear back from you peter. It's interesting to hear from someone that actually USED or has TRIED spektrum in thier boat. It seems that many just tell someone elses story. I mean, i do believe these people that they have heard of problems and you pretty much know that FASST is going to work 100% but to actually have someone give specific details on thier boat and say spektrum works fine is great. The problem for boats is that there are so many different configurations that can affect this problem. Even the fact that you have DX2, DX3, DX3.0, DX3.0s and DX3.0r (DSM2) and the multitude of receivers out there for these can make a difference. Then we put on top of that the type of hull, composite, power plant, size etc - the possible combinations are pretty much infinite. For one or even 100 people to say 'I tried spektrum in my boat and it was crap' is only a drop in the ocean (no pun intended). So peter, your tunnels is wooden construction right? And how high from the waters surface would your antenna be? Are you still running the full length of antenna on your SR3000? thanks for your input!
Posted on: 4/7/2009 12:35 AM by Author "Elnino" in the forum "RC Boats General Discussion"
http://www.rcuniverse.com/forum/fb.asp?m=8656673

RE: Spektrum SR300 antenna mod?
I think i'm prepared to have a shot at the mod. There are plenty of people here that suggest spektrum is no good in a boat but lets say for example this IS to do with water reflections - then getting the antenna further from the surface of the water should help. I've also read that some people only have problems when the water is glassy. This could also be why 10X8 is not having problems with his - The antenna is much more out of the water on top of the tunnel. Also though, a tunnel does not produce such a rooster tail as the prop is submerged rather than a surface prop like most gas boats. Either way, i think i'm prepared to give it a shot. As i said before, my boat is nothing special and in fact (other than the time i have put into it) the Spektrum RX would probably be the most expensive thing in the whole boat... The problem would be that given other peoples experiences, i am not keen to try it in it's stock form so it will be hard to tell if my antenna mod works, whether it will be because of the mod or pure luck. My theory is to get a U.F.L Connector and solder it to the underside of the board. I will then use a pre-fabbed 2.4ghz antenna on a pigtail. These are the connectors commonly found on laptop wi-fi cards... [image]http://www.hux.net.au/wp-content/uploads/2009/04/UFL_Connector.jpg[/image] Problem is, my pond is empty at the moment! Waiting for rain....
Posted on: 4/6/2009 7:12 PM by Author "Elnino" in the forum "RC Boats General Discussion"
http://www.rcuniverse.com/forum/fb.asp?m=8655621

RE: Spektrum SR300 antenna mod?
Could it be something to do with electric vs gas?
Posted on: 4/6/2009 8:47 AM by Author "Elnino" in the forum "RC Boats General Discussion"
http://www.rcuniverse.com/forum/fb.asp?m=8653604

RE: Spektrum SR300 antenna mod?
I also see that this guy uses an SR3000 in his RC Yacht with an external antenna mod: http://www.anderswallin.net/2005/10/spektrum-receiver-antenna-modification/ Reading his other posts, he's using a DX6 now but that is still Spektrum DSM Which further leads me to believe the problem is not due to water surface reflections. Perhaps it's the rooster tail?? Prop?? not sure.
Posted on: 4/4/2009 7:38 PM by Author "Elnino" in the forum "RC Boats General Discussion"
http://www.rcuniverse.com/forum/fb.asp?m=8648822

RE: Spektrum SR300 antenna mod?
ok, ok. Perhaps i'll get a cheap FM for the boat then - Something that is at least better than the AM i have in there now. It's not a multi thousand dollar boat and the area i have to use it is not overly big. I still don't understand how Spektrum can claim it is due to refelctions when futaba's system doesn't suffer this same problem. It's the same frequency. Yes, i know FASST changes channel every X ms but it's still the same radio frequency band. I acknowledge FASST is better but it still does not make sense. There must be something Spektrum is not telling us. The only other thing i can think of is that the prop generates the reflections, not the water and that somehow the FASST system swapping channels avoids this problem. Either that or Futaba just simply puts out more mw of power from the TX so the rf penetrates the water better. I don't believe that simply changing channels is going to change the laws of physics - either 2.4ghz is reflected by water or it's not.
Posted on: 4/4/2009 7:32 PM by Author "Elnino" in the forum "RC Boats General Discussion"
http://www.rcuniverse.com/forum/fb.asp?m=8648809

Spektrum SR300 antenna mod?
Hi all, I'm hoping for some advice. First off, let me say that i KNOW spektrum do not recommend the use of their products for water use (something about the water reflecting the radio which has to be crap since FASST is RECOMMENDED for water...?) Anyways, I have an SR300 (not SR3000) that came with my DX3s and i was told by the LHS they have used them fine in the water as long as the antenna is above the water level. Well, in my gas boat, the radio box is lowish in the water but i want to use the Spektrum because the AM radio i have in there now is crap. So, in trying to stick with what the guy at my LHS said and in combination with what i know about 2.4ghz in general I was thinking that i should be able to extend the antenna. i have a lot of experience with 2.4ghz wireless networking antennas, i have built them and modded heaps of USB wireless adapters to support external antennas so i know the theory behind it all. Spektrum is theoretically the same so the principals of the antennas should be the same. The main problem could be with impedance and possibly overloading the antenna driver circuit. My theory is to extend the antenna to be able to mount it higher on the boat but also extend the ground plane/shielding for the longer run using a shielded coax. Basically the same as the one on the old SR3000's but then expose the 30.5mm of 'core' at the end (30.5mm being 1/4 wavelength for 2.4ghz). The total lengthening of the antenna would probably only be 5cm, if that. I'd like to hear your comments if you have or do use Spektrum in your boats and/or if you have done any mods to the antennas to make it work as it should. it just seems a shame to have such a good radio but i'm being told it's not a good choice for a boat. P.S I thought it was funny that Spektrum failed to comment when i asked them "If 2.4ghz is reflected by water, why is it that Futaba's FASST system is recommended for use in boats - Since they both use 2.4ghz, wouldn't they both have issues"? Clearly it means that somehow their product is not as good as Futaba's. If only i knew that before i got into boats...
Posted on: 4/4/2009 5:28 AM by Author "Elnino" in the forum "RC Boats General Discussion"
http://www.rcuniverse.com/forum/fb.asp?m=8647144

RE: Building Big Block Maxx Help
+2 I am running a BB in my maxx and still have stock diff internals front and rear. I am running cheap GPM shells with the internals shimmed and i have never blown a diff. Run quality grease in the diff internals and try not to deliberately stress the internals and you'll be fine. +1 on the spooled diff too.... Go back to standard or it'll be almost impossible to stop it from spinning out in a turn on the dirt under power.
Posted on: 2/12/2009 12:19 AM by Author "Elnino" in the forum "Traxxas Monster Truck forum"
http://www.rcuniverse.com/forum/fb.asp?m=8467637

RE: Need help with T-maxx 2.5
[quote]when mine went bad it wouldn't move at all[/quote] It would have if you let it rev enough to get into second. The OWB allows the first gear to spin slower than the shaft when second is engaged. If you did not have it the gears would lock because of different ratios. Think about it, why would there be a OWB in there at all if that was not the case.
Posted on: 2/11/2009 9:50 PM by Author "Elnino" in the forum "Traxxas Monster Truck forum"
http://www.rcuniverse.com/forum/fb.asp?m=8467035

RE: Need help with T-maxx 2.5
I know this is an old thread but i have seen this before. The reason it 'jerks' into gear is because that's second gear! Basically, the one way bearing in the trans is shot so it spins on the shaft until 2nd kicks in which locks the drive gear to the wheels and off it goes.... It could be the shaft worn down too. Either way - The one way bearing is slipping.
Posted on: 2/11/2009 5:37 PM by Author "Elnino" in the forum "Traxxas Monster Truck forum"
http://www.rcuniverse.com/forum/fb.asp?m=8466068

RE: Aussie drifters in adelaide........any here??
I'm here in adelaide. Just getting in to drifting. I wanted something that was a bit slower and less likely to break than all my other RC's. I've been playing down at HH every now and then. Prb once a week or so. Now my mate has just bought one too so will be getting in to it a bit more..
Posted on: 1/12/2009 7:43 PM by Author "Elnino" in the forum "RC Drifting"
http://www.rcuniverse.com/forum/fb.asp?m=8351028