Sunday, 21 December 2014

Jim's XS 650

Test fitting to check compatibility of some wire wheels before they go off for Jim to fettle and the have new rims and 19"flat track tyres fitted.

Off with foot rests which weigh a great deal and begin to manufacture some lighter and purposeful items.
We have also dropped the front forks by an inch and a half and since the photos, removed the front brakes.
It is beginning to take a bit more of a flat track "attitude".





1930's Wolseley 15/50 Spl..

Some further preparation of the new cylinder block and running parts.
There is always a lot of "prototype" work when an engine of many new parts is assembled. It is so easy for "one off" items of such complexity to have a small error and sometimes, more surreptitiously, an accumulation of small errors. We cannot take anything for granted, and that is certainly not a criticism of those involved in the manufacture.

Here we have prepared and given the outside of the block a coating of Suncorite phosphating primer, a product developed for military use on gun barrels and precision items to protect, when used in conjunction with oil coatings or paint top coating it is extremely tough. The new block will go through further cylinder boring work and the primer will help to stop some oil deposits lying in the porous material surface. Internally all items have been painted with Glyptal for the same reason and the added benefit of free oil flow and to seal in the sand that migrates from the casting during the engines use and temperature cycles. A word of caution, from experience of seeing many engines coated in this paint,it is important that if applied to aluminium, it has to have been chemically or some form of very thorough cleaning. In service, aluminium items do seem to reject the Glyptal unless absolutely clean and I have noticed, it adheres more to some form of rough or cast finish. Glyptal flakes floating in the sump is a worrying sight!
Always think carefully with internal engine paint regarding the benefits and the risks, consider the heat cycles and the heat dissipation requirements and consider the fuels in use.
Incidentally, during the period, many companies used a form of shellac to paint the internal areas. Often it still resists even chemical removal after all of these years of use, even on aluminium (Rolls Royce).

The differing oil pumps fitted to variants of this engine may offer some advantages especially when limited by the availability of parts. We are considering using deep pump internal gears to offer a little more capacity, the same pump has an extended drive shaft bearing housing which would allow better support for the skew gears when compared to the standard items. Of course this will require further, time consuming modifications.

As loads and revs increase, it will be prudent to upgrade to a Duplex timing chain which will require some further test fitting and alteration.

The new crankshaft counter weights will not allow pistons to enter from the bottom of the engine with the crank fitted. The conrods cannot pass down through the bores from the top as the big end section exceeds the bore diameter. All rods and pistons will have to enter into and up through the bores prior to fitting the crank and bearing housings.

Cam phasing has been carried out and some general cam index position notes taken for final assembly. The cylinder head has yet to go for new bronze guides, slightly larger inlet valves and new valve seats which will have three angle cuts and blending to aid a little gas flow and valve to seat contact.

Combustion chambers have been cleaned and brightened and each chamber volume measured and dressed equal to that of the largest volume.









There are many areas of casting seam "flash", I missed this one so some more careful fettling will be required. (Below)














Sunday, 7 December 2014

Delage DISS

Cotter pins are such fiddly little devils to make as a one off.

 Time just rushes away, taking dimensions, finding and base machining a suitable steel bar then swap to four jaw chuck. Dial clock to index from the pin centre line for the offset thread, cut a thread and trim and de burr every thing. That's just the first stage. Now the next part of filing and fitting to get that "just so" snug and mechanically secure fit into the pins own unique location....phew and look at that time!


Now it is time to fit the pins to the brake "through" shaft in the gearbox bell housing and to prepare the historically bruised clutch fork faces to true.The shaft had been removed to clean and "free".
Generally the gearbox assembly has been checked visually but little work has been required, many items had already been recovered in the 70's before being stored. As mentioned before the clutch withdrawal mechanism has been created and modified from boxes of similar parts from other Delage models..






Wednesday, 3 December 2014

Words Cannot Introduce This Speed Record Fiat

But 1 minute 58 secs into this film says all you will need to hear!

video

https://vimeo.com/113158655   Follow this link to Stefan's films, art and news....

Tuesday, 25 November 2014

Flat Track Adventure, Yamaha XS650 Special

Racing moto cross on KTMs, enduring enduros with state of the art KTMs, long distance adventures on big V twin KTMs...the list continues. Time for Jim to get a new bike...an 80's Yamaha!
Why the change?...Well perhaps Sideburn magazine and Dirt Quake 3 UK begin to have a bit of an influence.

Elbow to elbow, head forward and eyes locked on to the first bend and the starters flag, Jim is astride his latest acquisition, hastily prepared to make the first of many transformation steps from road cruiser to flat track fugitive set in a moment to become a battle hardened, dirt oval, sideways racer in DIRTQUAKE 2014!

 Now Jim's fledgling racer sits in my workshop for the second of many evolution phases.

Estimating perhaps an equivalent 1hp gain for every 10lbs in weight loss this XS is in for some weight reduction. Removal of the many unwanted road bike brackets and fixtures will start the process. Footrests will be reworked to save considerable weight and re positioned to tuck up out of the way.
Wheels will be changed to spoked items suitable  for the correct 19" Flat track tyres.
Handlebar controls and throttles are to be replaced and the quick removal of the front brakes will be facilitated.

New carburettors and Boyer ignition will provide an initial step up for the engine, closely followed by a bespoke exhaust system to exit to the right hand side.

The story will continue as we follow Jim's Yamaha transition from XS to classic Seventies dirt racer destined for Dirtquake 2015 and  DTRA 2015 (Sideways 60 mph and no front brakes)!