A couple of queries after shakedown run

[iansoady]

I've just covered about 50 miles as a shakedown after recommissioning my 1961 Flash. It started very easily, with full air slide and flooded carb, and ran very well throughout. However, a couple of small issues:

1. I stopped for 15 minutes by Hatton Locks to enjoy the sunshine. On returning to the bike it wouldn't start. It was in bright sunshine so it was a bit difficult to see but there seemed to be a good spark at the plugs and they were a lovely fawn colour (B7HS) but absolutely dry. Eventually, remembering a similar problem I used to have with a 16H Norton, I tried flooding the carb - instant success. ISTR that the problem with the 16H was the carb heating up and vaporising the petrol, but I have a Tufnol spacer on the Flash and the carb wasn't hot. Any suggestions?

2. I was getting a bit of juddering and clonking from the front brake. When I stopped, I noticed that the nut holding the backplate onto the spindle (this is the 8" cast iron FWH with end caps on the forks) had loosened. I'd tightened it as firmly as I could on assembly. Any tips here?

Apart from these minor things, a very enjoyable ride. But I'm sure I wasn't doing 90 down the A435 as the speedo was suggesting.....

[A10Boy]

Blimey we go to Hatton Locks, its managements fav walking place. 

1/ It could be that you will need to flood the carb on every start up. Often I have to just slightly tickle my carb and never use the air slide. Maybe your float fuel level is a bit low. If it starts with a tickle and is otherwise ok, its OK.

2/ That nut needs to be tight to stay done up. I got a box spanner [off ebay] cos you cant get a ring spanner in the recess. use a bit of loctite and it will stay tight.

Regards

[bikerbob]

Hi there.
In regard to the float level I don't know if you already know this but to check the float level on your carb. If you look at the float bowl cover plate below the word AMAL you will see a small raised cast dot this is the level of the petrol in your float chamber. Now to check this what you have to do is make a temporary cover plate out of clear plastic place over the original cover align the 3 bolt holes then mark the dot onto the front of the plastic bolt the plastic cover back on the carb then turn on the petrol the level in the float chamber should come upto the dot if higher or lower you need to alter the float until it is correct.

[iansoady]

Thanks both.

Still getting to grips with it and learning its foibles.....

The Venom I had always needed full air slide after stopping for more than 5 minutes but as soon as it started I had to back it right off. I haven't started the Flash often enough when it's hot to get used to it.

Bob,

Yes I did know that and used to have an extended float bowl with a perspex end - now missing of course....

It does run very well and idles nicely, although I've had to screw the mixture screw almost all the way in.  I guess there may be a slight blockage somewhere in the idle circuit.

[lawnmowerman]

Hi Ian

I have to tickle my carb hot or cold - possibly movement and vibration while riding make the fuel level a little higher so is enough to keep the bike running. When I started my SR after the winter I had problems which were finally resolved by rewinding the mag but when I stripped the carb I found the pilot jet was partially blocked with dissolved fuel tap rubbers (now BAP) and bits of dissolved tank liner probably due to ethanol. The jet hole looked like it had a lacquer deposit on the inside so I fitted a new one from Hitchcocks. Ticks over fine now with the air screw out 1 1/2 turns.

Jim

[A10Boy]

An easy way to check fuel level, is to remove the cap from the pilot jet below the carb and push on a length of clear 3/16 plastic pipe then hold the pipe to the float chamber end cover [making sure that the end of the pipe is above the top of the cover] and turn the fuel tap on. You will see the level of the petrol in the pipe - its fast and simple and doesn't disturb the float chamber end cover gasket.

Andy

[iansoady]

Excellent tip Andy, I'll try that.

[bsa-bill]

Nice one Andy - if only I can remember it

I think what I need is a little booklet to hold all these little tips in, sort of Mrs Beeton's book of BSA management

[A10Boy]

OMG another Karma