Bernies Bike Shed

TRIUMPH B254F motor strip!

During the summer i took part in a ‘Sunbeam Club’  run in Sussex.I must point out the ‘Sunbeam Club’ is a club for pre 1940’s motorcycles and all makes! it’s not for Sunbeam motorcycles, but if you have a pre 1940 Sunbeam ! no problem. The run called the ‘Ixion run’  starts in a church grounds in Bexhill,Sussex. The run took place on a wonderful sunny day in May.I was looking forward to giving my new Triumph B254F a run in the  area of the ‘Battle of Hastings! I started off in high spirits but after a few miles my Triumph was giving loud noises from the engine!! my hearing is not good these days! so for me to hear the assorted sounds coming from the engine wasn’t good news! sadly i decided to return to base. A few weeks later the Triumph was on my ramp with a motor strip down ready to investigate the source of all the noises! They were coming from a worn main bearing, dynamo side! a very worn bigend bearing and a small end bush The main bearing was easy to replace the bigend and small end busche was sent to a expert in Essex where a new crank pin,bearing and conrod journal was made up.The only problem was the time period taken! The parts have to be harderned in a process which involves cyanide plus heat.A one off is expensive so a larger quantity lowers the price.there is a time delay before there is enough parts to be sent off. So now it’s October 4 months later! but i have a new shining bigend a small busche. The pictures below show the motor strip and assembly. So next May i will be on the same run but with a smooth ,quiet running Triumph?The work  carried out on the conrod,big end and small end was done by


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Me on the return! not happy, the Triumph making lots of noises!


‘Ixion run ‘at the start! What could go wrong!!


A plate made to withdraw the armature and flywheel.Plate locates on engine casing and the nuts pull the armature off the  crank


Armature and flywheel with withdrawal tool


Casing with new main bearing,new bigend and small end busche all ready


Engine still in frame but a crank strip down is possible! drive side is 2 ball bearings plus a worm scroll seal This idea of engine being excisable was a feature on all Triumph/TWN motors till the end of motorcylce making in 1957


Crankshaft new mains being pushed into place


Barrel on and a view of clutch side


Clutch slip is a problem! original spring right substitute left! will it work??


Drive sprocket and clutch in place 3 x steel and 2 x fiction plates


Motor almost complete,note the simple idea of crankshaft nut with a collar! so as you undo the nut it pulls the sprocket of shaft! so simple ,so German!!

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