My Thundercat

Had some decent conditions today, a bit windier than I hoped but nice and cold. Did about 15 top speed runs, some 2up and then some with just myself and a 30kg water ballast. Performance is the best it's ever been, managed 78.1mph on one run! 67.8 knots, even faster than I went at Coniston. Still a couple things to try
 
Not been out since then, doing a couple tweaks to the boat
 
Great week last week, was over in Skye for a few days and then made it to Easdale for Friday/Saturday. Covered 68nm on fri and 57nm on sat. Engine running pretty well although I think there’s water in the fuel, starting playing up a bit towards the end. Superb weather though!






 
A couple weeks ago my friend Rolf Magne Sunde passed away. I got in touch with him years ago about engines and tuning, and after Coniston I sent him my engine to tune. He was an absolute mechanical genius, lovely guy and we spent countless hours on the phone discussing all things Yamaha. He set a World Speed Record with one of these engines on an f4 catamaran at over 100mph in the early 90's which still stands today. We spoke every other day and he will be sorely missed.
I got this custom sticker made up a year ago to go on the new engine cowling which is now nearly ready to go on



 
New cowling is now on, 3D printed an intake section in the back which is a lot bigger than the standard one too

 
Anyone have any ideas on this? Engine is running strange, mid range has massive hesitations. If I can get it up to speed it sort of clears. Has been running like this for the last few runs now, filter is full of this stuff. I've changed the fuel, run it through a water seperater and it doesn't seem to be water. Cleaned the carbs, checked fuel pump
 
Seem to have sorted the water in the fuel tank, removed some worn rubber seals from the tank and made a U shaped breather to stop water going in. Also had an issue with the engine dropping onto 2 cylinders, turned out to be a loose bolt on one of the pickup coils under the flywheel. Engine now going better than ever, jets are 170/180/180, not running the additive any more as the supply has dry. Using octane booster with Toluene instead, plugs are the perfect colour so happy with that.

Booked accomodation for Coniston again this year, hopefully goes ahead! Need to find a copilot whos 50kg or less, any volunteers?
 
Records week is the first week of November, 1st-5th this year
 
More testing done yesterday, early morning had a couple hours calm. Consistent 76mph + each run, tried the new cylinder head I designed which gave a bit more power. Well chuffed with that! 76.7mph top speed, couldn't get my biggest prop to settle so need to try a couple setup tweaks.
New car too, Subaru Legacy 3.0 Spec B Auto


T shirts designed for Coniston
 
Been on a diet since September, gradually gone down from 76kg to 71.2. Started the keto diet on monday, hoping to get to around 70kg. Copilot is around 50kg if that. Will be intersting to weigh the boat again at Coniston and see how much difference there is from 2018
 
Getting on alright, running on Monday was all cancelled due to weather.
Tuesday was a bit too windy to be ideal, managed a couple runs not quite full throttle. First run hit 75.19mph max but only averaged 68mph over the two 1km runs. Second run moved my copilot forward for more stability, hit 72mph max and averaged 69.something.

One other thundercat here, running in the modified class, German crew with Hagen Jerzynski driving. They got a couple runs in then flipped at high speed, both taken straight to on site ambulance. Codriver ok, Hagen was kept in hospital and has 5 broken ribs. Quite a stark reminder of what can happen pushing one of these boats to the limit!

Today got two runs in, tried the 23p prop but wasn't as fast as the 21.5 which I've now put back on. Wind picked up in the afternoon so took the opportunity to climb the Old Man of Coniston, well worthwhile.

Will post more photos at the end of the week

Hagens boat:


My mate Andy White who's very kindly helping out for the week!



Helmets looking cool:
 
I had the last run of the day, getting very dark I couldn’t even the buoys on the south run. Had a moment just before the exit buoys, was flying before then.
Return run 72mph average, 76.43mph top which I’m happy with. Calmer tomorrow morning and second out so hopefully goes alright
 
Had an accident yesterday down at Coniston Power Boat Records Week, did a full flip at 75mph. Down to 0mph within a second, hard impact. I've a very sore back, Ciara Macleod a sore hand but both largely ok.
Engine cowling lost to the depths of Coniston water, an offering to the god of Speed. Helmets both damaged but incredibly grateful we were wearing them and proper lifejackets. Big thanks to the safety boat crews and to the paramedics.

Flew home last night with Mum & Ciara, Dad very kindly continuing with the boat. Got a New National Record which I'm surprised at, didn't get one clean run in all week but 68.40mph average in the P850 class; faster than the world record too.
Not really a representative speed, had 76.43mph top at Coniston and 78.17mph in testing.

Huge thanks to Andy White; you’re an absolute star. Thanks to Clive Lewis for his help all week too, my incredibly supportive family and to all my sponsors for giving me this opportunity

Douglas Curley for all his support
Tersius Swanepoel for his incredible propeller tuning
Rolf Magne Sunde for his engine tuning and advice

Lochs Diving Services
Seatrek Marine
GulfXStream Ltd
Mathesons Furnishings
Woodys Express Parcels
Forge Marine
Venture West
Jura Passenger Ferry
Uig Sands





 
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