Yeh I shaved 1mm from the head which gave 30psi more. Eventually put a TSR head on it which was slightly better again, along with the D1 exhaust. I've got the whole thing quite well documented here -...
Type: Posts; User: Roflhat; Keyword(s):
Yeh I shaved 1mm from the head which gave 30psi more. Eventually put a TSR head on it which was slightly better again, along with the D1 exhaust. I've got the whole thing quite well documented here -...
Hot
Haven't tried the new style but the old rubber hub ones were more desirable. Not sure if there's actually any difference in blade profiles
Agree with mike, and try not to keep the engine at a fixed RPM for too long, when you're at 2000 rpm just move the throttle up and down slightly to vary revs
That's a really neat solution, like that a lot
looking good
They should spin silently and with no play, it's usually fairly obvious when they've gone, they deteriorate quickly and make a lot of noise
Does anyone have the dimensions for the exhaust flange on a 70CES?
https://preview.ibb.co/mb2uTH/IMG_5815.jpg
Does anyone have the dimensions for the exhaust flange on a 70CES?
https://preview.ibb.co/mb2uTH/IMG_5815.jpg
I don't mean shimming it so the gears are too close together, just taking the tolerance closer to what it should be from factory.
Hey Jake, lapping looks like the way to go thanks mate. Did...
Alright, I've never tried shimming the gearbox but heard you can shim it tighter to gain some rpm. Not sure if there's much to be gained by balancing the gears seen as the diameter is relatively...
I meant I can't add anything such as lwp or a bullet point.
The gearbox works fine but shimming it to reduce the tolerance can help reduce friction. There's regulations for the bullet and skeg...
Standard Yamaha 70ces gear case, can't change the shape of it by adding lwp or point etc. Was going to balance the gears and re shim the gearbox at the same time
Hi Jeff, I'd heard of that being done, not tried it but I might try some back to back tests to see how it performs
cheers
Wondering what folk do to their gearcase to improve performance?
Was thinking of stripping all the paint off as it's quite thick and putting on one thinner coat. It's used it salt water or else I'd...
I would avoid the cleaver shape if you're running the prop fully submerged. The more blade area you remove the less pitch the prop will have
Couple good props here - https://www.facebook.com/forgemarine
You can read my build thread with my old tohatsu 50, we get 63.6mph with that motor now on a thundercat with an 18p Mercury Chopper -...
If it's the same as the Tohatsu 50D2 which I believe it is, rev limiter comes in at 5850. The crank shaft is pressed, it's generally not recommended to remove the rev limiter without welding the...
That's fast now!
Cool build :cool:
Always liked that phrase, the costs seem to increase exponentially the faster you go, I only paid £750 for the engine, the porting + other mods were £1200
There's only 1 fuel pump on the...
haha, its hard to go fast for cheap!
I run super unleaded here in Scotland, 97 RON
Hey Fred,
after all round power, engine is ported with 90hp carbs. The TSR head ive got has removable chambers so I could draw up some new ones and have them CNC'd
I've heard 34cc is decent, TSR...
Anyone have experience testing different CC head chambers on the ces?
I think they're the same diameter, just different jetting. The jets in the 60 carbs might even suit you better
Looks really sharp in blue!
Wouldn't have thought a bigger powerhead would fit under a 50hp cowl, I suspect it's just a tuned 50hp
That's a really smart looking solution, nice work!
Does anyone know of any smaller lower units that will fit the 70ces? It's quite a lot bigger than the 50hp, I think you could fit a 14" diameter prop on the 70
Also maybe worth thinking about a...
i believe the F50 gearbox will fit the 70, it fits the 70ces, have a look here - http://www.thundercatinflatable.com.au/forum/showthread.php?3493-70CES-Yamaha-Infanta-Thundercat-Build
I can't believe that you would get near 3 cylinder (70ces) performance from a 2 cylinder. When you're tuning the 3 cylinders it's extremely effective because the cylinders are 120 degrees apart,...
Is there any reason you would lighten the crank instead of the flywheel?
Thanks Tim,
Seems to be the general consensus - not as stiff as stainless but better than brass.
Regarding material, does anyone have any experience with Aluminium Bronze/NiBrAl? Seems a lot of companies prefer to offer this for casting as opposed to stainless. The strength and hardness figures...
Fantastic, thank you very much! sent you a PM
Got it thanks - sent a reply
I would certainly appreciate that thank you! I'll send you a PM
If mathrich wants a one or two maybe we can split them?
Thanks for the replies, I'll probably just get one printed in ABS for show. I was looking at metal additive printing but the prices are still very high.
mathrich - thanks for the link, very...
I'm looking to get a 3D model printed once I've finished my design, anyone have any knowledge on different forms of plastic? Generally available ones are ABS, PLA and Nylon. Looking at ProPulse props...
I found that photo on http://www.mccauleyandson.com/html/what.html
I've spoken to Joe McCauleuy, who reflects what you say Ron - these props worked well when through hub exhaust is required. I...
Yeh, I'm thinking with this design the exhaust hub will be structurally redundant, so to turn it into and over-hub exhaust prop you could simply remove the exhaust hub.
But for this project I want...
I'm just starting on this now, anyone have any advice regarding extrapolating the blade shape further into the hub? I want to remove the fillet where the blade joins the outside of the hub and move...
That's a shame, can you add cup?
Thats awesome, how are you making the inside of the hub?
Awesome project
Thanks zul8tr, that's all good information. I'm looking for literature on this, do you know of any good books regarding propeller design? I'm hoping to get Marine Propellers and Propulsion by John...
update on this, sent the propeller away, 11x18p Mercury Cleaver. Got the IGES file back a few days ago, here's a couple screenshots from Rhino...
Do you get any smaller gearcases for the 70ces? Was looking at bass or SST lower units, the 70 one seems fairly chunky