Blower belt drive, width of that good for 200hp+ (½" pitch). 8mm pitch is used on Pro blown motors and will easy handle 500hp. That little thing 30hp MAX. Make sure you unis are in the correct phasing. You might be getting flex in your primary shaft mounting plate, that kind of torque will flex pretty thick plate. Suspend both shafts between 2 bearings and make it solid.
So good to hear the red six screaming... Well until the belt let go again😬 absolutely love your work guys toranas / v8s / jetboats / fabrication.. And a few beers... It doesn't get much better looking forward to what happens next!😎👍🍺
Hey only just watched this build and great work there. Only thing I noticed is with the belt drive. Pretty sure the tensioner should go on the non drive side, that is so the jet is driven directly and any slack is at the tensioner. Same as cam belts and drive belts on a car.
One of my subscribers suggested to check you guys out and this thing is awesome! I’ve wanted to build a jet boat from a tinny for ages, I can’t see why a tinny wouldn’t be an easy and cheap platform. 🇦🇺
If I was starting from scratch again, I’d still use a tinny, but I’d use a Yamaha jet unit. Some of them have an aluminium induction housing and the whole unit could be welded straight into the boat. Plus there a bigger jet and they have reverse! And then I could have set the motor further back.
Try a duplex roller chain can get many sizes and stuff the guys over at statewide bearings are legends and reasonable priced we converted out stump grinder from poly chain belt to duplex roller chain and solved a lot of issues and strong and cheap
Looks like you need a nice beefy blower belt for your drive, I like the way you've gone about gearing it up, but like you said, it's a bit much for that belt to handle
good stuff, I will say that jet pumps do cavitate after a certain rpm, I'm not sure when that pump starts cavitating but I'd say it's somewhere around 10-11k rpm at the pump,
This is alot of weight and torque for that little jet, think about upping the size or getting some weight out, a alloy cross flow head will help. People retro fit other heads to the 6
I had to google the cross flow head conversion, but it appears you’re right! Seems like it’s quite a job though, maybe a little too much for this project!
Add trolling motor to front end just in case your boat dies again ... Find a way to use chain drive instead just use front end of timing chain area ....Just make sure every thing is level all the way around ............
Seems to have plenty of power for the jet. Maybe look at a 3:1 ratio and something much stronger for the drive. Not much room for a gearbox but maybe a chain drive would do it considering the power they handle on bikes. Might be a lot more pleasant driving the thing with a Muffler on it. I'm sure the noise will get old pretty soon on a long run.Ggood vid.
@@TheStuartstardust yeah Chain will make some noise but even with the engine Muffled I think it would still be Ok. If the engine was left with no muffling you'd never hear it. Box would be good but not much room to mount one is the main problem. Chains on Bikes aren't overly noisy if maintained and would handle all the power the Old red motor has to give.
and here i am seeing the OIL BURNER guy over here watching the guys build a boat. But on the point of going 3:1 here. I know a thing or 2 about jet pumps, and they dont handle that much rpm. Most actually shouldnt go above 10.000rpm. Not because they wil explode(wel they might, never tested it) but because they wil start cavitating at that point and that wil only destroy the impeller and make you slower. So i would say dont go higher then 8, maybe 9.000rpm, and it might actually allready be cavitating at that point.
@@glumpy10 as for the chain. Pretty sure a hayabusa makes a good amount of power and runs just a normal chain. I would put a guard around it tho. Not because of the noise, but if that chain lets go and hits that aluminium hull the boat wil probably become a 2 part design with no real ways of connecting the 2 parts back together.
@@gabbermaikel I was thinking more to use the Torque of the engine and keep it's revs down rather than having the highest Impeller speed. Using the engine torque would probably make it more economical too. I only know enough about those jetski engines to know the old red motor would have massively more torque to make up for the lack of RPM. Could probably gear the engine up so it hit max impeller Speed at 3000 RPM if that with no trouble. I used to play with red motors a lot and an inlet manifold with a pair of Su's ( just pair, not even Triples) and a set of extractors made a HUGE difference to a stock engine even in terms of power and economy. I even welded up a stock manifold to fit 2 Burgers like the old X2's and that made a difference as well. Be very easy for these guys with their Aluminium Fab skills. I am building some generators atm and going the same way. Oversize engines turning relatively slowly for less noise and wear and geared for where the genny needs to be. I just like torque not screaming Revs. :0)
had a few glass 16ft pluss 186 an 202 inboard fishing boats all weigh alot more than ya sick tinny alloy build mate.. you could step the engine to jet drive up to atleast 3.5 to 1.. still be fast out the hole 👍 doesn't weigh much
@@joelan93mtfworkshop89 the jet pump wil be spinning way too fast at that point and start cavitating. So it wil get slower if you spin it any higher then in most cases 8k rpm, maybe 9k if you are lucky. So if they want to go faster with this pump they should be looking for a different pitch jet impellor if there are any for this pump.
You need a Mazda 1300TC engine with a dgv Weber Will Rev to 8500rpm all day and never break Engine is at least 30/40kg lighter and basically the same power I used to blow away genuine XU1s in my 808 coupe with jetted standard carb. Everyone swore my car had a rotary...no mate you just got done by a 1300 4 banger with standard carb
