Photos i found in the drive cleanup Someones Homebuild masterpiece.

[thcl500j6]

Found these pictures in a seagull stuff folder on an old drive. No nothing about the engine at all but it looks like someone put a lot of work into it. It my ring a bell with some older , members. Sorry long time members.

I have made the pictures quite big so anyone interested, can see details, of what was done.
Hope no one minds.

[tambikeboy]

That's the way to do it...

[Charles uk]

I think I've seen that motor in New Zealand, at a place called Waiuku.

It's a 102 with reed valves & a Mercury leg, that was a very quick one if I remember right.

[Collector Inspector]

Well you have just reminded me that my Hotrod Gull stalled at the reed valve investigation.....2 years ago?

I was planning another way so back into it I guess.

Ordered some rather odd bits from Fleabay just now

I have friend with a mill which is required to progress.

I try to always stay clear of welded fabrication. Use the castings you have...

Gulls are FUN!

BnC

PS: Not having much luck in finding the old thread...

[Nudge]

I think I've seen that motor in New Zealand, at a place called Waiuku.

I think you are correct! I know nothing about though!

[thcl500j6]

I think i might have got the pictures from the old Kiwi seagull international site.
But i wouldn't swear to it.

I do remember another shot years ago of just the carb and crankcase, as well maybe someone else remembers more about this engine.

[Charles uk]

I asked the builder of this motor if he had any pictures or history, this is what arrived this morning.


Hi Charles, that engine cane about due to necessity, it was developed over a period of 5 years .. 3 of those spent racing the Team NZ shore crew boat in the The Great Race on the Waikato River in NZ .. our rules restricted the “Open Class” to a Seagull powerhead and Seagull parts only, with the exception of the leg.. at that time there were only 3 5R’s in NZ one was in the possession of the TNZ Shore Crew Team, which was later race prepared by one of John Brittains engineers (motorcycle World Champion), the second by a despot in Kinloch NZ, the third by the importer from Christchurch NZ.. this left me out in the cold, so to compete, this 102 was developed over a period of 3 years, the powerhead itself was a “freak” it would happily rev to 5k plus revs in standard form with a swept Thornycroft prop and a standard 102 leg all day.. in fact did 4 Great Races with min servicing each year and never missed a beat. Bear in mind we were in full swing in those times with new hull design concepts appearing all year round and this base motor was the main test/race engine, that way you were able to compare hull to hull, during that time we had approx. 10 engines that we were working on, measuring and comparing trying to find the difference in the motors … there were small differences which we tried to replicate, but could never get a better performer than we had, after 4 Great Races of 88miles and countless hours of testing, the motor was stripped down , honed, another set of rings, new bearings, cleaned up ready to face all comers, it was at this time “Open Class” was declared and I adapted the Mercury leg to the motor and moved into “Open Class “ against the depots from Kinloch as there was 2 of them at this point, (brothers), we were all raced trimaran hulls of around 28/30 ft.. I achieved approx. 13mph with the mods that year, leaving the Kinloch Kids broken on the banks. The next year TNZ Shore crew arrived in the middle of the night with their creation complete with 5R and severely trounced us all, at this time I started reading about reed valves and crankcase induction and made “old faithful, continually testing and modifying over the winter and following Summer, to finally face up against TNZ in 97?? .. to be beaten with an average speed of 18+ mph by a better resourced team and a driver that weighed 60kg, during those days I was rounding up 110kg. During the Club debrief of the event I pointed out I could not compete against a 5R with a motor that was 40 years old , the Club at this point included 5hp Seagull Sports into the Open Class category, so I proceeded to import the first Seagull Sport into NZ , with spares it was at this time that TNZ gifted me their “old fibreglass” boat, as they were going to make a new creation out of carbon fibre,……….. after consulting an old friend who raced 3 point hydros powered by Ford 10 engines capable of 70+ mph, I cut into the TNZ boat and made the necessary mods , during this time I had been developing the Hickman Sled with the hope of using that and keeping the “long boat”as a backup,…. for some reason I couldn’t get the Sled past 20mph, even when powered by a propped 10 hp Mercury , on reflection I think the inverted hull with a single engine in the middle without some form of hull deflection a la Boston Whaler in the middle was the problem, I think the volume of leg “drag” negated the advantages gained by the “inverted’ hull.

We raced the Sled against the “long boat” when still in TNZ ownership, once, in severely choppy conditions on Auckland Harbour and the Sled flew from wave top to wave top with Des Hudson at the wheel, it was a picture to see, the long boat suffered due to the troughs and couldn’t get above them, whereas the Sled with 20mph velocity just “flew “ from crest to crest… a “beast” to ride as there was a fair amount of driver movement required to keep the vessel trimmed and not have the whole thing flipping backwards with a head wind, unfortunately I lost this hull during an attempt to lighten and sadly I dispatched it to the burn heap, but the dream lives on when the Ford leaves the garage this winter you could very easily see another “Sled “ appear …. Unfinished business there.

To continue the “Long Boat” story…. Must have been 98?, all construction was complete, all systems thoroughly tested complete with moveable fuel tanks for ballast balance etc the race duly started with TNZ getting a great start, by Leamington Pool we were running great with me about 10m behind holding with 75% throttle, which I was very happy with the passing manouvre was completed by Ngauruwahia and I led at this point by about 50m, slowly creeping away on 80%, everytime I went around a corner out of view, I would put the coals to her until they reappeared, then back to 75% .. finishing the day at Rangiriri 4 mins in front and running at 75% .. Des and I were pretty chuffed about that, got horribly drunk along with TNZ that night as we planned an assault on Bermuda.

As we settled down to sleep at some ungodly hour I heard the hammering of a prop on a vehicle tow ball.. at that point I knew we had them fuked,…. next day the race set off as per usual, Ihad no intention of racing or leading .. so drifted along in the wake of the quick boats and then started my run for home after Mercer at about 80% throttle, didn’t need to “bash” the engine and run the risk of failure, added a couple of minutes and was pretty happy about that …. After that we saw the birth of the short speed boats pioneered by that Kinloch Kid was pity he never finished a race, as the speed was pushed out to over 30mph from there on in … there you have it my friend, you will notice there is no technical or measurements in the article,.. edit as you wish and distribute as you please.. cheers JC

The Kinlock kid is the same gentleman I call the Mad Professor who's current project is building a motorcycle out of junk parts that have never seen a motor bike before, to ride.

[tambikeboy]

Fascinating story thanks for sharing C...

[Charles uk]

I was hoping for more detailed pictures, but this is racing, & if you saw them he'd have to shoot you!

But you do get an indication of how much work goes into this madness.

[JERSEYMAN]

Really amazing story to read, incredible dedication,

Thanks to all

[Rig pig]

Brilliant thanks

[Chicken]

Here's a short clip of one I made a while ago to test the theory

[Collector Inspector]

A very tidy job is that Chicken.

I am going the other way so as to not increase the volume of the crank case to that extent.

BnC

[Charles uk]

You've got to keep an eye on those Kiwis, Sneaky, sort out Covid by doing the job properly, then start bastardising Seagulls, why didn't they follow our example & completely mess up our response to everything!

This really hurts, That's a very nice piece of work Cam!