Racing in Australia with an ES2

storm42 said:

I have an engine and I have sourced an aluminium head for it with a view to tuning it but that is as far as I got, mainly due to racing a twin.

I would be interested in what you have done to make it rev to 8500 and not lunch the motor. What crank, rod and piston do you use and what work has been done to the head, pretty much all your trade secrets so I do understand if you decide not to divulge this info.

The running gear would closely follow what I have on my Seeley.

Ralph.

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Hi Ralph,
A brief synopsis of a possibly wasted life:

"ES1" was an "iron" engine with improved porting, a 32mm Amal Concentric carb, 0.400" valve lift cams with appropriate timing, 12.5:1 on methanol, a modified standard crank 79 x 100mm. Single plug cylinder head set @ 32 degrees BTDC. Lightened rocker gear, standard cam followers. Revs were limited to 6,200 rpm pulling cleanly from 3,300 rpm. and probably made about 46/47 rear wheel BHP. Semi close gearbox ratios chosen to suit the power characteristics of the bike. Factory cases. "Tuned" length exhaust. The motor was punchy but ultimately fragile. (A photo of a young me on "ES1" circa 1981/2 Amaroo Park Sydney/NSW).

"ES2" was may first all allloy motor saving considerable weight, the distribution of which resulted in a significant improvement in the handling of the bike. Steel press up crank 80 x 100mm with a custom steel Carillo 7" rod and an INA big end. Modified standard main bearing arrangement. Arias custom piston 12.8:1. 48mm inlet valve, std diameter exhaust valve both in 21 4N 5/16" diameter stems. Gold Star or equivalent valve springs (R&D) set to provide 100lb seated/ 180-220lb "on the nose". 0.425" peak lift at the valve with appropriate valve timing. 1 3/8" Amal G.P. carburetor jetted for methanol. 15 degree down drought inlet with improved flow. exhaust port reduced in diameter by closing in the floor. Twin plug magneto set at 31 degrees BTDC (could have used a little less). 4 speed close ratio box. Factory cases. "Tuned" length exhaust. 5 speed Quaiffe box. 49 rear wheel BHP, but now a more robust motor. (A photo of "ES2" at Oran Park/Sydney circa 1988-90).

'ES3" my second alloy motor. Further improved head with similar valve sizes to "2". Similar steel crank but now with a more robust needle roller main bearing arrangement in slightly modified factory cases to accept such. 1 1/2" Amal GP and then later a 38mm Gardner both tuned for methanol. Twin plug magneto . Currently 14:1 with custom C.P. piston. 80 x 100mm crank , INA big end, 7 " custom Carillo rod all basically as per "2". 0.425" max inlet/exhaust valve lift. "Tuned" length exhaust. Now using 22 degrees of ignition/ twin plug magneto. 6,800 peak use rpm preferred ,but will rev cleanly to 7,000 rpm if required. 51 rear wheel rpm with a "fresh" engine. Bike weight with full fairing, oil but w/o fuel 107kg (236lb). A good package that could be built by anybody with the skill, time and patience. A frequent podium finisher, capable of winning with a good rider on board. I have had a few. (Photo of the current piston design x 2) + Photo of ES3 (rider Mike Soderland) 1st, ES3 (rider John Cronshaw) 2nd, and Glen English (Beale G50 3rd - Eastern Creek INCA meeting a long time ago .

"ES4" uses a "full house" 90mm bore engine. One piece crank (2.1" crank journal/slipper bearings). Custom titanium rod 1.86 ratio). Modified high speed/high flow pump providing 70 p.s.i hot (regulated). 60 degree included valve angle, 1.62/1.58 custom rockers providing 0.625"/0.585" valve lift. Titanium valves. Roller cam followers. Appropriate valve spring choice to accommodate with 140lb seated/365 lb at full lift which translates to 590lb back at the follower. Special slotted cam gear wheel arrangement to accurately set the cam timing. Eccentric rocker spindles to set the tappet clearance ("lash" I believe is the US term). Substantial main bearings (caged needle rollers), running on a 1 3/4" D.S journal and 1 1/2" T.S. Improved rocker box holding down arrangement. Modified standard crankcases. 13.6: comp custom piston. A lot of cylinder head work with a compact shallow chamber (have a look at the Ilmor Mercedes chamber). 60+ rear wheel BHP. Pulls cleanly from 4,000 rpm. Custom hydro-formed tuned length exhaust. 5 speed TTI 'box.

I doubt that anybody will ever be as foolish or committed to build a better push rod Norton single cylinder engine, and I have been privileged to have seen inside a few here, and around the world. Peter Lodge (NZ) runs a similar set up with his own independent proven ideas and development program. (Photo of the engine on it's first complete assembly).

It is of course all in the detail which would take too much to go into here. After 40+ years of development, I don't think that I can extract much more performance from the humble ES2 engine, and I am probably now a little exhausted.

Sorry but these photos are out of sequence, but I am sure that you can sort it out.

Cheers - Geoff

Thanks for sitting down and documenting that Geoff, a lot of food for though there and fantastic looking bikes too. Of course the first problem for us in the UK is, with the classic club we cannot use methanol in bikes younger than 1939.

Everyone is in the same boat though so the reliable rev ceiling you have achieved along with the light weight is where I would want to be.

My interest is road racing rather than track, but that means going into Europe these days and that has stopped for now because of the Covid thing although I am looking at Ireland, I am getting a bit old for much of a future on track anyway but a smaller lighter bike may extend my time racing.

The roads can dictate that the engines are run at high revs for longer due to the nature of the course so the reliability is key.

I am getting ready to go to Cadwell this weekend and I notice Mark Cronshaw is racing, John is usually with him if you would like a message passing on to him.

Thanks again for the info.

storm42 said:

Thanks for sitting down and documenting that Geoff, a lot of food for though there and fantastic looking bikes too. Of course the first problem for us in the UK is, with the classic club we cannot use methanol in bikes younger than 1939.

Everyone is in the same boat though so the reliable rev ceiling you have achieved along with the light weight is where I would want to be.

My interest is road racing rather than track, but that means going into Europe these days and that has stopped for now because of the Covid thing although I am looking at Ireland, I am getting a bit old for much of a future on track anyway but a smaller lighter bike may extend my time racing.

The roads can dictate that the engines are run at high revs for longer due to the nature of the course so the reliability is key.

I am getting ready to go to Cadwell this weekend and I notice Mark Cronshaw is racing, John is usually with him if you would like a message passing on to him.

Thanks again for the info.

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I may have replied to late, but if you see John say a hello from Geoff and Hendo.

Methanol does have some advantages re engine cooling (which can be a problem with start up in cold weather). the higher consumption would rule it out for long road events.

Careful (i.e. correct) attention to ducted air flow through the engine I believe to be critical once you start making good power. If you wish to understand this a little better refer to "Air Cooled Automotive Engines" - Julius Mackerle. This was the text that Peter Williams used when designing the factory Commando racers. Air does not willingly go where you might expect without a little cohersion. Hint: reduce the dead space inside the fairing and produce simple "dams". Sometimes a block of polystyrene strategically placed can make a significant difference.

ES234 said:

I may have replied to late, but if you see John say a hello from Geoff and Hendo.

Methanol does have some advantages re engine cooling (which can be a problem with start up in cold weather). the higher consumption would rule it out for long road events.

Careful (i.e. correct) attention to ducted air flow through the engine I believe to be critical once you start making good power. If you wish to understand this a little better refer to "Air Cooled Automotive Engines" - Julius Mackerle. This was the text that Peter Williams used when designing the factory Commando racers. Air does not willingly go where you might expect without a little cohersion. Hint: reduce the dead space inside the fairing and produce simple "dams". Sometimes a block of polystyrene strategically placed can make a significant difference.

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I will have a read of the Julius notes, thanks. I may need to do something with my current race bike, I have run out of Avgas that i mix 50/50 with Shell Vpower and in the last race it was pinking badly as it got hot.

I had a word with John this morning and he was pleased to hear from you, he would like you to email him for a chat if that is OK, I guess he has either lost or not got your email.

Again thanks for the advice.

storm42 said:

I will have a read of the Julius notes, thanks. I may need to do something with my current race bike, I have run out of Avgas that i mix 50/50 with Shell Vpower and in the last race it was pinking badly as it got hot.

I had a word with John this morning and he was pleased to hear from you, he would like you to email him for a chat if that is OK, I guess he has either lost or not got your email.

Again thanks for the advice.

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I will give John a call.
Re your pinking problem you as I am sure you understand may have to look at an alternative fuel as well as pulling out a little ignition timing. It has not been legal to run Avgas here in Australia for a few years, and the fines if caught are substantial. Happy to have a private chat at some stage should you wish. Cheers.

I believe our only fuel restriction apart from not running methanol is that it must be under 105 octane, the avgas I get is 100LL so not a problem, although it is difficult to get hold of, I have some on order for this weekend and the next race is 3 weeks away so the problem should be sorted. I only use 26deg advance as it is a 920 motor.

Our Shell VPower is supposed to be 98/99 octane but now I don't believe that, I haven't heard that motor pink before but have always used the mix until this weekend. We live and learn.