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[jawa-enfield]

Hot inner bearing raxes on cold crankshaft, yes that worked well, then the crankshaft in the freezer and crankcase with new bearings at 120 Celcius in the oven.. take it out and 'boom' the cold crankshaft falls in!
Apply very thin layer of gasket maker (non silicone) add paper gasket, again thin layer of gasket maker and then the other hot crankcase on the still cold crankshaft.

It worked and i was worrying for nothing....

[Adrian]

It shows you were concerned enough to make a decent job of reassembly.

A.

[jawa-enfield]

Only thing i want to sort out is non-stiffer-non India valve springs... I got the rumour Terry's aero springs can do the job, but do not know a type nr, or got a reply from a seller if he has fitting ones for a bullet 500..

[jawa-enfield]

Okay, finding the nuts/bolts for the engine casings.. after too long time because/and..despite having put all nuts/bolts and so in separate trays, i cannot find a fitting nut for 2 engine studs, i have 1 mysterious hole in the engine and.. can someone identify these 2 special shaped ends?
I do not recognize them in any drawing..
(something from the generator?)

[stinkwheel]

Those look like ground diameter/dowelled studs.

No sense of scale from your picturebut I suspect the smaller one will be one of the two 1/4" ground diameter studs on each rocker block.

The other will probably be for the very bottom crankcase joint at the 6 o'clock position as you look at the side of the engine, should really be first one in so it aligns everything.

[jawa-enfield]

Hmm i don't think i understand any of this..
The smaller, from which i have one, should be somewhere at the rockers?
Bigger one is lower engine case?

In meanwhile try to remove mainshaft sprocket for close ratio set, but it won't come off, it just doesnt, destroyed 2 pullers on it, heating does not work. I guess i have to make another order for the main shaft withoudt the sprocket and the boss and oil flinger apart.

[stinkwheel]

Closer inspection suggests perhaps not the rocker stud, as I said, scale is tricky.

Suspect Parts 16 and 19 on this diagram. https://www.hitchcocksmotorcycles.com/p ... -pages/498



I initially thought one of them might be part 33 on this diagram. https://www.hitchcocksmotorcycles.com/p ... -pages/607

[jawa-enfield]

Thanks very much! Does 'dowled' mean this shape?

Took myself out for a walk.. at a workshop they should have a press to expell the unwilling sprocket form the mainshaft and install the new one?

[stinkwheel]

Most engine casings have dowels, small cylindrical steel pins that fit tightly into the two crankcase halves (on motorcycles they are often hollow and are found round one or more of the bolt holes in the crankcase). They fit halfway into each crankcase half to ensure they pull together in perfect alignment and stay there while the bolts are done up. You also commonly see dowel pins on plain bearing shells in car engines.

On a bullet, there are no dowels. In theory, you could rotate the crankcase halves around the crank slightly until the bolts/studs are in place and done up tight which would side-load the main bearings. What they have instead is one stud which is made a larger diameter than the others (ground down very accurately from an even larger piece of bar stock) and is a very tight and accurate fit in its hole. This acts like a conventional dowel and ensures the crankcase halves are properly aligned during tightening.

They do the same thing with the rocker blocks on the newer iron barrel bullets (maybe not on yours). Each rocker has two standard and two ground diameter studs to ensure they stay perfectly aligned.

[vince]

Hi, there is a hollow dowel surrounding the bottom rear bolt. Vince