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I got this Genesis a few weeks ago on ebay. Overpaid but oh well. I ran it in the way the last owner did and went into overheat/ limp mode quickly. The esc and motor didn't temp that hot? But it seems like a big boat for the stock electronics. The last owner put water drains in it, lots of epoxy and looks like a bear to remove. I don't really like them as I feel like they can fail. Keep or remove? It seems like a bandied for a water intrusion problem. Also, I am thinking of removing the under-hull water pickups and just using the dual pickups on the rudder. Any problem with this? Or should I stick to the bottom pickups and eliminate the rudder pickups? My goal with this boat is to run on 6s around 80 mph saw runs. I have not ordered a motor yet, but was thinking a 4082 or 4092 in a 1750 kv or so. I have a Castle Hydra on its way, I was thinking of putting it in my blackjack 42 and the stock spectrum in the Genesis? I am going to attempt a carbon inlay and fill the sponsons with resin/carbon mixture as I have seen a few threads about it here. I want to change out the water exits too. Any input is appreciated. Good and bad.
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Well, if it were my hull... I would serious float test in the tub to determine water ingress before ripping out the drains. If you are fortunate enough to discover the source of the leaks , I'd just plug the drains with a gob of grease, easier to get out if you find you still need them and they are not the source of the ingress. -
Ditch the auto-bailers. If you don't want to pry them out of the hull, at least fill them with silicone caulk. They cause more issues than they solve.
Your cooling system is a mess. Bypass the cooling through the motor mount. It's useless. Keep the underhull pick-up. They work well. Use one water pickup to feed the rear barb on the motor jacket, then exit out the forward bard and out the side of the boat. Twist the water jacket so that the forward barb is at the 12:00 position. Use the other water pickup to cool the ESC, then out of the hull. Cap off or remove the third water outlet in the side of the hull.
Check out the build thread I did on a single motor 37" Genesis. That boat ran 90 on 6S and 103mph on 8S.Vac-U-Tug Jr (13mph)Comment
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That is a beautiful build you did there fweasel. I agree, the cooling system is a mess. I got the hull stripped, I'm going to patch the holes with fiberglass, fill the sponsons with resin/glass, then attempt a carbon inlay. Probably going to look like *!***!***!***!**, but this is my first boat build, and I don't really care. I'm not going to use the stock electronics, I am thinking about a seaking 180 with a 4082 or 4092, or the stock spectrum esc out of my bj 42. I am not sure if the 180 will push it? IMG_3259.jpgComment
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I just got data logging setup to see what boats actually consume in energy. My 27" mono pulls 2000w to go about 50-55mph. my 42" cat pulls about 4000w to go about 50-55mph. My blackjack 24 pulls about 1600w to go about 50-55mph. On 6s if you prop this boat to pull 3000w on a 4092, which is quite a hot setup, it will pull about 150A. On 8s with the same prop and RPM it will pull about 110A. I have found wires and batteries really dont like to continuously output that much for more than a minute or so. voltage drops and temps go up fast after that.
so I say it depends on what you want to do. if you run 8s and keep the RPM's/KV lower you should have plenty of ESC.Comment
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What kv motor would you go with if I were to run 6s and 8s batteries? I ordered the Castle hydro, I am thinking of putting it in this or in my blackjack 42, and the stock spectrum in this. I'm not sure just yet? Currently I have flooded the sponsons with epoxy, and I'm beefing up the hull with carbon/epoxy before I attempt an inlay.
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I ran a TP4060 1750kV in my single motor Genesis with a 250A ESC it ran great on 6S for as many saw passes as two 5000mAh 3S packs could support, and near the thermal edge on 8S, 2 passes tops.Vac-U-Tug Jr (13mph)Comment
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thats a 56" hull? somewhere in the 900-1200kv for 8s. it doesnt really matter you will just adjust prop size to accommodate your RPM range. I know fweasel says he ran a 4060 on 6s but I personally run a 5670 on 12s in a 42" catamaran @ 6kw. and Truckpull on here has a long thread about his 41" cat with twin 5670 TP motors pulling 8kw to run in the 80's. IM far from the most experienced here though.Comment
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a 56mm can is far too large and heavy for a 37" shallow catVac-U-Tug Jr (13mph)Comment
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[QUOTE=Bande1;769345]thats a 56" hull? somewhere in the 900-1200kv for 8s. it doesnt really matter you will just adjust prop size to accommodate your RPM range. I know fweasel says he ran a 4060 on 6s but I personally run a 5670 on 12s in a 42" catamaran @ 6kw. and Truckpull on here has a long thread about his 41" cat with twin 5670 TP motors pulling 8kw to run in the 80's. IM far from the most experienced here though.[/QUOTE
Its a 37" hull. I'm going to order the TP 4060 1750kv, fweasel, thanks for chiming in. I think it will pair well with the Castle Hydro.Comment
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[QUOTE=paDDY;769363]4070 is not much more in cost. $20 extra dollars 800 more watts. if you get a lower KV you will pull far less amps on 8s to go the same speed.
I tell you this only out of experience trying to push 4kw @ 6s when 90% of batteries struggle to push 120A. not trying to harp on you. just throwing it out there as something to think about before you purchase.
checkout this video released today showing Zeee packs real C rate at 14C. Which is going to be the case for almost all "budget" batteries. a 4060 will need 150A continuous output on 6s. These things even 8000mah only output about 112A at 50% charge. on 8s you would need 110A to max a 4060.
Last edited by Bande1; 07-25-2023, 05:09 PM.Comment
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[QUOTE=Bande1;769364]Thanks for your input Bande1. Thats definitely something to consider motor and battery wise. I do have a decent amount of Zee batteries; I am slowly going over to Gens Ace as they seem more accurate about their capacities. I am heading out on vacation tomorrow and placing my order with OSE this Friday so still in a bit of research mode.
4070 is not much more in cost. $20 extra dollars 800 more watts. if you get a lower KV you will pull far less amps on 8s to go the same speed.
I tell you this only out of experience trying to push 4kw @ 6s when 90% of batteries that struggle to push 120A. not trying to harp on you. just throwing it out there as something to think about before you purchase.
checkout this video released today showing Zeee packs real C rate at 14C. Which is going to be the case for almost all "budget" batteries. a 4060 will need 150A continuous output on 6s. These things even 8000mah only output about 112A at 50% charge. on 8s you would need 110A to max a 4060.
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[QUOTE=Bande1;769364]I'd say its very hard to find a hobby battery sold today that is over 35C when it is accurately measured by a good battery testing device. Even high end expensive packs that advertise 250C will rarely be above 35C or maybe 40C at best. One of my friends owns a hobby shop and has tested many different lipo packs on his equipment, he said he has never had a pack commercially sold rate over 40C in real testing
4070 is not much more in cost. $20 extra dollars 800 more watts. if you get a lower KV you will pull far less amps on 8s to go the same speed.
I tell you this only out of experience trying to push 4kw @ 6s when 90% of batteries struggle to push 120A. not trying to harp on you. just throwing it out there as something to think about before you purchase.
checkout this video released today showing Zeee packs real C rate at 14C. Which is going to be the case for almost all "budget" batteries. a 4060 will need 150A continuous output on 6s. These things even 8000mah only output about 112A at 50% charge. on 8s you would need 110A to max a 4060.
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Yep, the big lipo load testing thread over on RCG has been running and testing for more than 10 years. They have never had one test higher than 40C, and even those rates will get the battery leads themselves scorching within 45 seconds.
And not a single one of those real 30-40C best in class packs they have tested come from any of the supposedly "premium" expensive brand names most are familiar with. Those expensive brand names are typically the worst performing packs you can get, and at 2-3X cost of the best ones they testComment
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