Hi guys just wanna get a bit of feedback if possible..
my mates who is a fibreglasser has a 52" mono deep v boat mould hes gonna make me up a hull and top and i was thinkin of putting a 49cc mini bike motor in it . ive been around rc monster trucks a while now and want to try something different. i have a few old trucks lying around i was gonna pull down and steal the radio gear,high torque servos etc out of.. what size flex shaft , prop etc should i be aiming around? the motor revs to around 20,000 rpm so by end of buld i would like to hope to get 100kph 60(mph) out of the big girl. thoughts and comments would be much appreciated. oh and my mates building one for himself so any tips to give me an advantage much appreciated..

Cheers Rob

my mates laying the hull/top this wk so ill post pics asap!

Hi if its a minimoto air cooled one well the carb is on the bottom of the crankcase which is a no no on a boat as you can,t get the engine low enough for the centre of gravity,just my thoughts on the matter and will be interesting what others say.regards Darren

Hi darren
Its similar to a minimoto. im mounting it flat in the boat same as it came out of the bike. it fits i have about 50mm to spare so the centre of gravity will be low as possible.

Robdog.

Be aware that a 49 cc (heavy) minimoto with that many revs in a 52" hull really is an overkill.
I know that as the experience, that I have gathered her at MGB, tells me that my own 40 cc Blata (a minimoto made special for modelboating) is much more than I need in my own 56 x 12" wooden mono (still in build).
If you really want to install the 49 cc monster in a 52" hull, I strongly recommend that you put it VERY low - and in a deep hull at least 14 or 15" wide.

Good luck. Send pics!

Woodie.

I tend to agree with Woodie on this one.... It's not so much the torque of that engine...but ya better get it real low!!! You've got to keep us updated with pics on this one Buddy!!!!!

GOOD LUCK!!!!!

Hey guys

Thanks for your input its much appreciated
im the kinda guy that goes big or goes home with all my rc trucks run 100kph+ so i kinda like speed but i do agree with you woodie in that 49cc may be a bit of an overkill but hey if i can pull it off then its gonna HAUL ASS Nobody wants to be at the back of pack!! my mates near finished the hull so ill take some pics of the engine sitting in it to give you guys a bit of a visual of what im up against..

as you can see plenty of room for plenty of power

Hi have you thought about cooling the engine?by look of it you will need to make it watercooled.I had the same engine but ended up not using it due to loads of issues,will be good to see how you get on and solve the problems you will come across.Keep us posted as the build comes on.Regards Darren

I tend to agree with Dazzido. Cooling can be a problem.
But if you keep the engine bay open, it might work with the air cooling.
Worse than this, I think, is how the exhaust port is placed. As I see it on the photos it faces directly to the bottom of the hull. This means that you have to angle the motor at least 90 degrees to get space enough for the exhaust tube. This also means that you will have to give up that fancy air-filter. In a MGB it should'nt be needed anyway: No dust on the water.

Just my five cents.

Woodie.