Post big bang - Whitsend A10

[muskrat]

" its a small journal and according to big mike reads 1.223 inch"
Std sml journal is 1.461" - 0.040 = 1.421. Is that a typo, micrometer miss-read???
Cheers

[charles whitfield]

Oh dear, thanks again
Can we agree to leave it as a typo?
Its 1.420
:-))

 

[charles whitfield]

I'm afraid to say the valves will be RS as well Charles.
Similar to my A65 blow up, rod little end missing. Could that have started the ball rolling. Mine was making a rattle for some time before it went bang, the big end bearings weren't too bad.
Cheers

Thanks Muskrat
Yep - I put some spirit in the cylinder head (for a change) and the valves are badly damaged
I have decided on a second full rebuild - I have roped the missus, in bless her. Dog still looks worried   

[orabanda]

Hi Charles,
RD250, or RD400 in the background?

Your choice of twins, 2 or 4 stroke, is excellent!

Richard

[charles whitfield]

Hi Richard
It's my old RD250 - I have had it about 24 years
but sadly its going to have to go now to fund the BSA - it's been a dilemma really since it's not very comfortable for us to go out on - a bit on-off resulting in banging helmet syndrome!
But unusual since it has a mag alloy drum brake wheel on the back
Hey ho
Charles 

[charles whitfield]

Sit-rep
Valves bent, guides damaged = full head refurb
Crank looks OK after a good polishing
Cylinder barrels need major re-engineering - Gulp
Mag going off for refurb just to be safe - works but slightly wobbly
Now the rest of it is coming to bits - Gearbox next
and then new spokes, tarted up paintwork, some more S/S nuts and bolts, bags of polish
and then a run out
and thanks in advance for your help that will doubtless be needed
Cheers
Charles
   
     

[muskrat]

Your spoiling the missus mate. Carpet, padded seat, glass of drink. Better not let mine see that picture.
Cheers

[charles whitfield]

 

[bsa-bill]

 I recall  one of you colonials  telling me  that If your missus could get into your shed her chain was too long.
This was long before this forum and it's cultural ethics existed


Helmet on -------- duck

[charles whitfield]

Been doing some more inspection work and although I have trawled the previous posts, I need reassurance please
Valve stems measure 2 x 0.310 and 2 x 0.311
In the guides, with the valves close to shut, I can detect about 5 thou deflection at the tappet end of the shaft (worst case)
It sounds OK to me, but then again, I am a bit sensitive just now
Would that seem OK to the collective wisdom?
Cheers
Charles 

[Butch (cb)]

I have a pal looking out for an RD250/400 at the moment ...

[charles whitfield]

Hi Cyclobutch
Thanks for the message - I am resigned to this year being lost to repairs.
After I dragged the RD out and polished it for sale, we had a reminisce, and rather than have no bike at all, we have brought it out of retirement
Once the A10 is up and running again, we will certainly sell it though
And it's moving on already, some more parts sorted through kind forum members - lovely place to be!
Thanks everyone
Cheers - Charles

 

[muskrat]

Those figures sound OK to me Charles. Is that new valves in old guides or new?
Cheers

[charles whitfield]

To be honest, I really don't know. It pre-dates me
But I have a feeling the head had been redone before I bought it - the rocker bushes and all seems still sound. big chunk of fin missing though
These are the inlet and exhaust vales from the undamaged side
I am a little concerned about the blue seat area, but a good grinding in will sort it - no pitting
Cheers
Charles
   

[BSA_54A10]

Inlet runs red hot so it will be blue if not black.
With modern fuels I tend to use a much thicker contact face than the old days around 3/16"
And the 3 angle cut seems to have worked a lot better than the usual 2 angle job