Twin Weed Eaters
08-21-2010, 01:12 PM
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Twin Weed Eaters
Ihave seen a few boats with twin weed eater eangines. Obviously the boat has to be a good size.
My question is Ihave seen some engines that look like they are connected to each other and some that run side by side.
What is the reason for this and how is it done?
Can the engines be different types of motors?
If you run two different drive systems wouldn't the props possibly spin at diffrent speeds?
I am just trying to get an idea of how this is done beacuse Iam thiniking of building a 72" mono and possiby putting two motors in it.
I tried to find some threads on this type of thing but didn't really have any luck, hopefully someone can point me in the right direction to find some info.
Thanks,
Jeff
My question is Ihave seen some engines that look like they are connected to each other and some that run side by side.
What is the reason for this and how is it done?
Can the engines be different types of motors?
If you run two different drive systems wouldn't the props possibly spin at diffrent speeds?
I am just trying to get an idea of how this is done beacuse Iam thiniking of building a 72" mono and possiby putting two motors in it.
I tried to find some threads on this type of thing but didn't really have any luck, hopefully someone can point me in the right direction to find some info.
Thanks,
Jeff
08-21-2010, 02:04 PM
#2
RE: Twin Weed Eaters
I'll take a shot at answering in the order that you asked them.
You can get the RCMK twin (2 cylinder inline) or some Zen's hooked together. For a mono you're really better off going this route as in the turns you may unload one engine and over-rev it instead of using 2 single cylinder engines.
No. Two different engines will be way off in terms of HP, RPM, power curve and other factors.
72 inches is a lot of boat. You're going to need something big to haul it in plus you're going to need help to get it launched. Add transom hardware and it's going to be longer yet.
You can get the RCMK twin (2 cylinder inline) or some Zen's hooked together. For a mono you're really better off going this route as in the turns you may unload one engine and over-rev it instead of using 2 single cylinder engines.
No. Two different engines will be way off in terms of HP, RPM, power curve and other factors.
72 inches is a lot of boat. You're going to need something big to haul it in plus you're going to need help to get it launched. Add transom hardware and it's going to be longer yet.
08-21-2010, 03:41 PM
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RE: Twin Weed Eaters
The size of a 72" in no problem to haul I have a van and it would fit in it nicely.
I think a big boat build would be fun.
You can get weed eaters for next to nothing so I was thinking just to see how it would handle with the two in there would be interesting.
If there was two motors I am assuming it would mean more power, two motors doesn't equal double the speed obviously but it does mean more hp to move a larger boat.
I have seen side by side weed eaters in boats before like I said with two props running.
The thread I saw was two john deer motors I can't remember the size of the boat they were in.
So would it be better to use a larger motor something like a 50cc motor then try to put two engines in it?
I think a big boat build would be fun.
You can get weed eaters for next to nothing so I was thinking just to see how it would handle with the two in there would be interesting.
If there was two motors I am assuming it would mean more power, two motors doesn't equal double the speed obviously but it does mean more hp to move a larger boat.
I have seen side by side weed eaters in boats before like I said with two props running.
The thread I saw was two john deer motors I can't remember the size of the boat they were in.
So would it be better to use a larger motor something like a 50cc motor then try to put two engines in it?
08-21-2010, 04:00 PM
#4
RE: Twin Weed Eaters
With anything larger than what we commonly use you're going to run into more difficulties such as you're going to have to fabricate your own motor mounts and will have to use the exisitng exhaust system (cannister nufflers). Even with John Deere's, Homelite's and the other old whacker motors, parts just aren't around like they used to be for upgrades.
A 72" hull isn't going to be cheap, even used so myself I can't see using out-of-date powerplants in it.
A 72" hull isn't going to be cheap, even used so myself I can't see using out-of-date powerplants in it.
08-21-2010, 05:11 PM
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RE: Twin Weed Eaters
Iplanned to build the hull, Ihave 72" plans. The motor Iwas thinking of maybe using is http://www.monsterscooterparts.com/49enwimapust.html they are used in mini bikes and scooters so upgraded parts are available.
Some people use this motors also for mini mud motors and I thought it would be a good choice.
What motor would you recommend to put in it trying to keep things as cheap as possible of course don't want to spend a fortune to build the thing.
I like to try things different sometimes doing things the hard way or different route can be fun and challenging.
Some people use this motors also for mini mud motors and I thought it would be a good choice.
What motor would you recommend to put in it trying to keep things as cheap as possible of course don't want to spend a fortune to build the thing.
I like to try things different sometimes doing things the hard way or different route can be fun and challenging.
08-21-2010, 05:13 PM
#6
RE: Twin Weed Eaters
Your idea of a pair of weedwacker motors (either inline or side by side) is certainly do-able - but I am not sure the effort involved will yield the performance desired.
What 72" mono did you have in mind. I have seen 70" monos moving at near the 40mph with a stock zenoah. You could put an inline weedwacker motor in there and do 20mph or 30 mph. Weedwacker motors are heavy and really lack the power that even a stock marine motor can generate. A zenoah is probably 2-3 times the HP and probably 30% more RPM while being 1/2 the weight and 1/3rd the size (plus water cooled).
Connecting a pair of weedwacker motors would be a fun project - but I am not sure it would be the best choice for your boats performance.
Another economical contender might be a pocket bike motor. If you got your hands on a Blata clone you would have a lot more power and torque than 5 or 6 weedwackers and an easier project to install in your boat.
What 72" mono did you have in mind. I have seen 70" monos moving at near the 40mph with a stock zenoah. You could put an inline weedwacker motor in there and do 20mph or 30 mph. Weedwacker motors are heavy and really lack the power that even a stock marine motor can generate. A zenoah is probably 2-3 times the HP and probably 30% more RPM while being 1/2 the weight and 1/3rd the size (plus water cooled).
Connecting a pair of weedwacker motors would be a fun project - but I am not sure it would be the best choice for your boats performance.
Another economical contender might be a pocket bike motor. If you got your hands on a Blata clone you would have a lot more power and torque than 5 or 6 weedwackers and an easier project to install in your boat.
08-21-2010, 05:42 PM
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RE: Twin Weed Eaters
ORIGINAL: Justaddwata
Your idea of a pair of weedwacker motors (either inline or side by side) is certainly do-able - but I am not sure the effort involved will yield the performance desired.
What 72" mono did you have in mind. I have seen 70" monos moving at near the 40mph with a stock zenoah. You could put an inline weedwacker motor in there and do 20mph or 30 mph. Weedwacker motors are heavy and really lack the power that even a stock marine motor can generate. A zenoah is probably 2-3 times the HP and probably 30% more RPM while being 1/2 the weight and 1/3rd the size (plus water cooled).
Connecting a pair of weedwacker motors would be a fun project - but I am not sure it would be the best choice for your boats performance.
Another economical contender might be a pocket bike motor. If you got your hands on a Blata clone you would have a lot more power and torque than 5 or 6 weedwackers and an easier project to install in your boat.
Your idea of a pair of weedwacker motors (either inline or side by side) is certainly do-able - but I am not sure the effort involved will yield the performance desired.
What 72" mono did you have in mind. I have seen 70" monos moving at near the 40mph with a stock zenoah. You could put an inline weedwacker motor in there and do 20mph or 30 mph. Weedwacker motors are heavy and really lack the power that even a stock marine motor can generate. A zenoah is probably 2-3 times the HP and probably 30% more RPM while being 1/2 the weight and 1/3rd the size (plus water cooled).
Connecting a pair of weedwacker motors would be a fun project - but I am not sure it would be the best choice for your boats performance.
Another economical contender might be a pocket bike motor. If you got your hands on a Blata clone you would have a lot more power and torque than 5 or 6 weedwackers and an easier project to install in your boat.
The link I posted is for a 49cc pocketbike motor just not sure on the performance of it only that it is larger then obviously a 25cc motor. I would like to do something different and not stick a zenoah in it.
The blata idea sounds interesting what type of setup would be needed for something like this?
08-21-2010, 05:59 PM
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RE: Twin Weed Eaters
I still think twin weed eaters wold be neat and fun to do because it would be very low budget. If I did choose to go this route would I have to do two different drive with two props or how would that work?
08-21-2010, 06:07 PM
#10
RE: Twin Weed Eaters
ORIGINAL: spede18
The link I posted is for a 49cc pocketbike motor just not sure on the performance of it only that it is larger then obviously a 25cc motor. I would like to do something different and not stick a zenoah in it.
The blata idea sounds interesting what type of setup would be needed for something like this?
The link I posted is for a 49cc pocketbike motor just not sure on the performance of it only that it is larger then obviously a 25cc motor. I would like to do something different and not stick a zenoah in it.
The blata idea sounds interesting what type of setup would be needed for something like this?
08-21-2010, 06:11 PM
#11
RE: Twin Weed Eaters
ORIGINAL: spede18
I still think twin weed eaters wold be neat and fun to do because it would be very low budget. If I did choose to go this route would I have to do two different drive with two props or how would that work?
I still think twin weed eaters wold be neat and fun to do because it would be very low budget. If I did choose to go this route would I have to do two different drive with two props or how would that work?
I did a 70" apache with a pair of chainsaw motors in it but later downgraded to a single saw motor - made for a lighter/faster boat in that instance.
08-21-2010, 07:31 PM
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RE: Twin Weed Eaters
Good info, what dos an engine like this cost?
Also you said you have done chainsaw motors obviously another possible engine source for a boat this big.
Any threads you can point me to that have build ups on a chainsaw engine build?
Also you said you have done chainsaw motors obviously another possible engine source for a boat this big.
Any threads you can point me to that have build ups on a chainsaw engine build?
08-22-2010, 07:27 AM
#13
RE: Twin Weed Eaters
There's an old thread on RCU where a guy used twin weedeaters in a boat. Maybe get more info from him. http://www.rcuniverse.com/forum/m_25...tm.htm#2512231
08-22-2010, 02:04 PM
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RE: Twin Weed Eaters
Old post for sure. I wil see about contacting him. Here are some videos on you tube http://www.youtube.com/watch?v=Z9Vf71Ty6Q8 of a boat with twins can't tell if he is running two prop or not.
Then there is his one a rc pane engine http://www.youtube.com/watch?v=S4JZx2jcmqg. So it is def do able just need to figure out best way.
Then there is his one a rc pane engine http://www.youtube.com/watch?v=S4JZx2jcmqg. So it is def do able just need to figure out best way.
08-22-2010, 02:21 PM
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RE: Twin Weed Eaters
I found the boat I was talking about with the twin john deere motors http://www.rcgroups.com/forums/showthread.php?t=1101078
08-23-2010, 04:54 PM
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RE: Twin Weed Eaters
LOL good luck doing a project like this on the cheap! And you mentioned that twice. You're going to have a grand into this project easy!
Think about it you want to build a 5 foot long projectile you hope will go over 40 mph! You haven't mentioned if this is your first boat or not but it kind of sounds like it, there are a lot of expensive things your going to have to buy, spending a couple hundred bucks on an engine is the least of your worries! I've got 300$ into a 2 foot long nitro boat and I already had the radio and lots of assorted rc bits and pieces!
The first thing is it has to be safe, you're going to have to do some quick talking it it goes out of control and t-bones some ones ski boat!
This is seriously not a project where cheap should be the first concern.
Think about it you want to build a 5 foot long projectile you hope will go over 40 mph! You haven't mentioned if this is your first boat or not but it kind of sounds like it, there are a lot of expensive things your going to have to buy, spending a couple hundred bucks on an engine is the least of your worries! I've got 300$ into a 2 foot long nitro boat and I already had the radio and lots of assorted rc bits and pieces!
The first thing is it has to be safe, you're going to have to do some quick talking it it goes out of control and t-bones some ones ski boat!
This is seriously not a project where cheap should be the first concern.
08-23-2010, 06:41 PM
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RE: Twin Weed Eaters
ORIGINAL: siberianhusky
LOL good luck doing a project like this on the cheap! And you mentioned that twice. You're going to have a grand into this project easy!
Think about it you want to build a 5 foot long projectile you hope will go over 40 mph! You haven't mentioned if this is your first boat or not but it kind of sounds like it, there are a lot of expensive things your going to have to buy, spending a couple hundred bucks on an engine is the least of your worries! I've got 300$ into a 2 foot long nitro boat and I already had the radio and lots of assorted rc bits and pieces!
The first thing is it has to be safe, you're going to have to do some quick talking it it goes out of control and t-bones some ones ski boat!
This is seriously not a project where cheap should be the first concern.
LOL good luck doing a project like this on the cheap! And you mentioned that twice. You're going to have a grand into this project easy!
Think about it you want to build a 5 foot long projectile you hope will go over 40 mph! You haven't mentioned if this is your first boat or not but it kind of sounds like it, there are a lot of expensive things your going to have to buy, spending a couple hundred bucks on an engine is the least of your worries! I've got 300$ into a 2 foot long nitro boat and I already had the radio and lots of assorted rc bits and pieces!
The first thing is it has to be safe, you're going to have to do some quick talking it it goes out of control and t-bones some ones ski boat!
This is seriously not a project where cheap should be the first concern.
08-23-2010, 06:56 PM
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RE: Twin Weed Eaters
ORIGINAL: spede18
Well it will be my second boat if I choose to build it. I am taking everything into consideration which is why I am asking questions about ow to go about things and when I say cheap I mean I am trying not to go buck wild and spend a fortune when I can do things on a budget.
ORIGINAL: siberianhusky
LOL good luck doing a project like this on the cheap! And you mentioned that twice. You're going to have a grand into this project easy!
Think about it you want to build a 5 foot long projectile you hope will go over 40 mph! You haven't mentioned if this is your first boat or not but it kind of sounds like it, there are a lot of expensive things your going to have to buy, spending a couple hundred bucks on an engine is the least of your worries! I've got 300$ into a 2 foot long nitro boat and I already had the radio and lots of assorted rc bits and pieces!
The first thing is it has to be safe, you're going to have to do some quick talking it it goes out of control and t-bones some ones ski boat!
This is seriously not a project where cheap should be the first concern.
LOL good luck doing a project like this on the cheap! And you mentioned that twice. You're going to have a grand into this project easy!
Think about it you want to build a 5 foot long projectile you hope will go over 40 mph! You haven't mentioned if this is your first boat or not but it kind of sounds like it, there are a lot of expensive things your going to have to buy, spending a couple hundred bucks on an engine is the least of your worries! I've got 300$ into a 2 foot long nitro boat and I already had the radio and lots of assorted rc bits and pieces!
The first thing is it has to be safe, you're going to have to do some quick talking it it goes out of control and t-bones some ones ski boat!
This is seriously not a project where cheap should be the first concern.
I just love it when someone starts to argue with the voice of reason.....lol[sm=lol.gif][sm=cry_smile.gif]
08-23-2010, 11:09 PM
#20
RE: Twin Weed Eaters
OK, I just gotta ask as I don't feel like going through your posting history, what is/was your first boat?
This is quite an undertaking for a second boat, ambitious to say the least.
When it comes to cheap, I'm right there but have learned that there are places not to skimp. I also know that with twin motored anything that the PITA factor goes up by a power of three, not two.. I've been doing this RC boat thing for a while now and srill haven't grown a big enough set to try any twin powered boat. My patience gets a good workout as it is with nitro and gas powered boats with single engines, with twins I'd probably go further over the edge.
Seriously, do a little more thinking before making too big of a move and ask yourself if you think that you're ready to go this far this soon. I do a lot of wishful thinknig myself but have learned my limits. I don't tihnk my doctor will raise my meds right now to a higher dosage.
This is quite an undertaking for a second boat, ambitious to say the least.
When it comes to cheap, I'm right there but have learned that there are places not to skimp. I also know that with twin motored anything that the PITA factor goes up by a power of three, not two.. I've been doing this RC boat thing for a while now and srill haven't grown a big enough set to try any twin powered boat. My patience gets a good workout as it is with nitro and gas powered boats with single engines, with twins I'd probably go further over the edge.
Seriously, do a little more thinking before making too big of a move and ask yourself if you think that you're ready to go this far this soon. I do a lot of wishful thinknig myself but have learned my limits. I don't tihnk my doctor will raise my meds right now to a higher dosage.
08-24-2010, 01:45 AM
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RE: Twin Weed Eaters
Iam in the process of building a 48" mono.
Ihad no doubts it would be an undertaking and Iam always up for a challenge.
Mainly I just thought it would be neat to have a twin setup on a boat which is why I started to look into it and start to ask questions about it.
Obvously a 72" boat is very large I was possibly even thinking of downsizing it to a 60".
So what your saying is if Iput two motors in the boat it will not double in speed but it has to atleast get some gain am Iwronge?
Ihave seen a lot of boats with twin zenoahs in them which is why Iwas thinking a twin weed eatr can not be all that far fetched of an idea.
Time is certainly on my side for this becaue I will not embarq on something that is going to be way over my head.
Research , research, research and then plan, plan, plan, unless somewhere in there is wow this is to much to undertake and not worth the time
Ihad no doubts it would be an undertaking and Iam always up for a challenge.
Mainly I just thought it would be neat to have a twin setup on a boat which is why I started to look into it and start to ask questions about it.
Obvously a 72" boat is very large I was possibly even thinking of downsizing it to a 60".
So what your saying is if Iput two motors in the boat it will not double in speed but it has to atleast get some gain am Iwronge?
Ihave seen a lot of boats with twin zenoahs in them which is why Iwas thinking a twin weed eatr can not be all that far fetched of an idea.
Time is certainly on my side for this becaue I will not embarq on something that is going to be way over my head.
Research , research, research and then plan, plan, plan, unless somewhere in there is wow this is to much to undertake and not worth the time
08-30-2010, 07:11 PM
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