R12 update

[Bigsieuk]

Hi all,

The tale of two R12's (twice the frustration, twice the costs).

I sent my grey R12 mag to Germany for a rebuild so that's off the road.

The tan R12 has it's engine back in back from John Law at BEMW here in the UK. Well the good news is it starts, runs for about 20 secs then splutters and farts and dies. When I attempt to open the throttle it coughs even worse, backfires then dies. I've swapped carbs and it is still the same, plenty of fuel coming from tank.

Moving the advance-retard makes no improvement either. A tooth out on the mag perhaps?

Any help to finally get one of them on the road after 4 years will be appreciated!

Regards

John

[meredith7493]

If 2 carbs both exhibit the same symptoms, then the next step is leave the gas cap off to ensure the fuel flow is actually strong. Then open the exhaust the ensure exhaust flow.

After that, it sounds like the magneto is next.

$.02
Paul

[Bigsieuk]

I'll check with cap of now and update.

Regards

John

[Bigsieuk]

Just ran 4 litres through fuel line with fuel tank cap on tight.

Mag breaking down?

Regards

John

[Beemer54]

Libel laws prevent me from re-telling the horror stories I've been told about John Lawes but if one tenth of what I've heard is true then to receive a nicely running engine back from him is the exception rather than the rule!
I'm in the U.K. and have just rebuilt a badly mis-treated R12. If I can help at all then p.m. me and we'll swap phone numbers.

[jrapose]

I thought we were all friends on this web....and we didn't bash folks.... not fair... to John.. To me it sounds like some little sort of fuel problem... possibly the mag is out a tooth.... but not fair to the mag rebuilder. It's just a cheep shot.

Joel

[Bigsieuk]

I understand the issues forums have with posters criticising suppliers/contractors but in this case I can tell you what I have found. I was told the bores had had new liners - the liner in the side I have taken the head off is scored and I haven't even run the bike for more that 3 - 4 minutes on idle as it wouldn't run properly.

The exhaust valve is still slightly open at TDC and doesn't seem to close for about 180 degree of the cycle. there is fresh swarf in the valve inspection area. That's what I found this weekend in 1 hour. I haven't contacted John law of BEWM yet so I'll let you know what his response is.

Should we criticise suppliers/contractors? If it impacts where we spend our money and what service we get, then yes we should. Would any members be disappointed if they'd spent money on a product or service only to find that previously here had been issues with a product or service and the feedback hadn't been available?

Bigsie

[Bigsieuk]

Having spoken with John he has suggested I bring the engine back to him to have a look at.

Regards

Bigsie

[jrapose]

That is exactally the proper response...... and he did it... if he were a flake he would have given you six reasons why it was not his problem..... and drop it.... this is such a small community that we have to be friends to survive.... folks that don't play fair are not long in business. Remember why we are in this business of playing with old bikes... there are WAY easier ways to make money...

Joel