Wednesday, 29 August 2018

You can't keep them forever

Much as I like to hoard stuff, there comes a time when you realise that you will never use this piece of timber or all of those used spark plugs you've carried from house to house since you were 16. It pains me to say it, but bikes are no different and much as you love them there are many different machines to sample and precious little time to do it. Am I feeling my age? Maybe, but I also feel a certain desire every time I see a bargain on eBay (there are such things occasionally) or discover some mechanical marvel that I don't have space for. We need to find some direction, or we will be drifting aimlessly until we run out of money or time - or both.

My bikes fill certain needs, if we take a look at what is in the garage at the moment:

  • Ariel SQ4 - the summer bike, the fast touring bike, the long distance bike. Perfectly happy with A road cruising at 60 mph, it's big and comfortable. Restored a few years back, it has occasional problems but is the reliable first choice.
  • Ariel W/NG - the winter bike, for slower sightseeing trips through the countryside - a bike for bimbling around at 50 mph on Norfolk's B roads. Recently recommissioned, it's still shaking down and spends more time off the road than the SQ4.
Then we have two more bikes that don't get used very much, or at all:
  • BSA Bantam - another bike for slower sightseeing trips through the countryside, it was in regular use until the W/NG came along to fill the same role. 
  • Ariel FH Huntmaster - in bits, collecting parts. It will have very similar performance to the SQ4 when it is done
So there are really three positions here, to be filled with one bike each since I don't have the space to store any more:
  1. The fast, long distance bike
  2. The country lane plodder
  3. The restoration project
So here's the summary:
  • The SQ4 fills the #1 role currently
  • The W/NG fills the #2 role currently
  • The FH fills the #3 role
  • The Bantam is surplus to requirements and will be first against the wall when the revolution comes
In the future, the FH could fill the #1 role and the SQ4 could be sold on; the #3 role could be replaced with a prewar single which would fill the #2 role when ready...

Just a thought...

Tuesday, 28 August 2018

Solex Emulsion Tube Repair

Regular readers will know that I've had a few problems with misfires lately. I've cleaned the carburetter several times, reviewed and serviced the ignition system and fitted a tufnol spacer and a heat shield to reduce the carburetter temperature. This has worked to an extent, but I still have an occasional misfire. Cold, my 1951 SQ4 runs beautifully – it’s smooth and responsive. Hotter, it seems to stumble when opening up again after slowing for a roundabout or some other obstruction. This stumbling clears itself quite quickly, after which the bike will pull as it should. Occasionally you will get a cough or the feeling of holding back.

Stripping the carb revealed that the emulsion tube was not in great shape, it was slightly bent and has a long hairline crack along maybe half of it’s length. The bend is probably due to it's location and the fact that it is possible to remove the float bowl with the carb in the bike, which leaves the emulsion tube vulnerable - if you are not careful removing the float bowl, you can catch it on the emulsion tube and bend it.

One of my theories is that the area of the float bowl casting forming the well around the emulsion tube is still exposed to engine heat, though I believe I can grip this with an ungloved hand after a run. The tufnol spacer and the heat shield have made a huge difference to carburetter temperature.

The first job was to straighten the tube. I put the straight section in the lathe, and brought a dead centre in the tailstock up to the air jet, to indicate the eccentricity. A bit of judicious bending, guided by the centre, had the emulsion tube straight again.

This is the emulsion tube, after my wiped solder repair. That crack was along most of it's length which would clearly upset the mixture.

Now, David Jones has new emulsion tubes for £20 plus postage, so that would be the way to go. However, if this doesn't cure the misfire, and I think the misfire might be down to ambient temperature, I'll be glad I kept that £20 in my pocket.

We'll test it later this week. Ambient here is now anywhere between 10 and 18 C, so we may not be able to give it a proper test until next summer...