SUNBEAM S7 and S8 MOTORCYCLES
  • SUNBEAM MOTORCYCLES. HEADER PAGE.
  • SUNBEAM NEWS and START PAGE
  • About the bike.
  • Distributor Internals
  • Redundant spark ignition.
  • Coil Information.
  • Beam-Spark Ignition Unit
  • FOR SALE
  • Smiths Chronometric Speedometer
  • Calibrating Smiths Chronometric Speedometer.
  • Speedometer Drives.
  • Companies and Products.
  • My other bikes.
  • The Horn. and Rear Brake Spring.
  • HOW TO PAGE
  • Modifications Page One
  • Modifications Page Two
  • Modifications Page Three
  • Dipsticks,sumps and oil weirs.
  • The Electrics
  • Sunbeam Dynamo in depth.
  • Repairs and Maintenance.
  • Carburettors
  • S8 Front forks.
  • Full width front brake on the S8.
  • Top dead centre.
  • Your Sunbeam.
  • All things wheels.
  • Data Sheets.
  • Engine breathing and oil leaks.
  • Putting the engine together.
  • Stainless Steel Exhaust
  • Tools
  • All things final drive
  • I80 Degree Crankshaft
  • Completed engine speed ignition sytem.

                   

The Mark 2 Six volt Beamspark ( positive earth ) kit is  £ 90 (complete). This is the ignition unit, distributor cap and coil.                   Post free in the UK.

 Comes with complete fitting instructions.

Two years warranty on all kits.


              



                       Today's date is 25th March. 2023.       
                     

Beamspark kit 12  volt negative earth ( Ignition unit, distributor cap and coil £105 post free UK ) !
                  Immediate delivery on all kits.
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To order full kit of either six or twelve volt please pay to the following bank account.

                 Name :  John Moseley
              
                  Sort code : 20-41-12

                  Account number : 73145123

The same bank details apply if you wish only to purchase a coil or a distributor cap.


I need your full name, address and postcode sent to my email address :    john @sunbeams.co


 I also forgot to mention that my Beamspark units fit very well on Morris Minor cars, well really anything with contact breaker points and coil ignition, both six and twelve volt !

It has to be pointed out that the six and twelve volt Beamsparks were developed for the Sunbeam S7 and S8. They are a points assister only and cannot enhance the performance of an engine. They do however make the contact breaker last for many thousands of miles without any adjustment and of course replace the worn distributor cap and rotor.

Buy a twelve volt Beamspark unit at £ 35.
Buy a six or twelve volt coil at £ 35
Buy a aluminium distributor blanking cap at £ 35

All items post free in the UK.


This website is a collection of thoughts and ideas some of which have been put into practice, other ideas are still out there. The Sunbeam bike lends itself well to modern upgrades and improvements while still retaining its original charm. I hope you enjoy perusing my webpages, please feel free to contact me.

   My E mail address is :                                     john@sunbeams.co
                                                                                  john@sunbeams.email

The website can also be found at                             www.sunbeams.co
                                                                                   
                                                                                    www.sunbeams.website

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I would like to make a few comments about the Sunbeam engine and its design that may dispel some misconceptions that seem to abound with British motorcycle engines.
Overheating of rear cylinders.........need I say more on the Ariel Square Four !  It seems that everyone owned one or knew someone that owned one and the rear cylinders overheated ! If there was that many Square Fours sold they would still be selling them today !
Basically what I am getting at is the air cooled engine has to run hot to be efficient. Yes we know the Sunbeam has a rear cylinder but what everyone forgets is the engine is physically bolted to a ruddy great cast aluminium gearbox which is a huge heatsink. Remember the Sunbeam only turns out 25 horsepower and that is only at maximum revs. So each cylinder can turn out 12 horsepower max.
The Sunbeam engine is oil cooled as well as air cooled, that is why the sump is bolted solidly to the rest of the engine, why do you think there are so many holding studs ?
Running the engine hot gets rid of condensation in the cambox and in the space in the crankcase. Hot oil flows better to to the crank and camshaft. Hot oil boils off condensation and keeps clean.The oil pressure in the Sunbeam is only about 35 PSI, which is OK as it is not oil pressure that is important but oil flow capacity. Keeping the oil flowing at maximum capacity can only be achieved if the oil is hot.
On several runs last year round Holland Belgium and France top speed recorded on my Sunbeam was 80 mph, this was only for a mile approximately whilst overtaking a convoy of petrol tankers on a busy motorway in Belgium. Most of the time the bike ran at 60 mph in the company of two Goldwing Aspencades for two to three hours each day. Upon returning home after 900 miles the engine was ticking over perfectly and still does today. What I can say is fitting a stainless steel exhaust system kept the cylinder head temperature even by absorbing any hot spots so that carburation kept spot on. In other words tickover remained fairly constant whatever the engine temperature.

So there you have some of my opinions.





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