Author Topic: Sacrilege!  (Read 2512 times)

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Offline tck

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Sacrilege!
« on: 10 Aug 2013 at 11:30 »
Hi
I have a 1948 T35 with a set of Amals and a set of Bowdens neither are satisfactory with the so called petrol nowadays and they are both well worn. I would like to retire them to the shelf especially as I am contemplating a long trip. Has anyone tried a set of modern carbs like mikuni I could easily turn up some angled short clip adaptors and an air filter would be nice if I could fit it in. Setting and experience would be worth hearing.

Offline Ian

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Re: Sacrilege!
« Reply #1 on: 12 Aug 2013 at 00:08 »
If the carbs are worn why not reco them ? I don't understand why the modern fuel would have anything to do with how they run ? There are thousands worldwide running fine.

Offline tck

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Re: Sacrilege!
« Reply #2 on: 12 Aug 2013 at 06:09 »
"word wide" includes countries not stupid enough to include ethanol in their petrol
Burlen and surrey cycles do not make small size pre monoblocks anymore
refurbishment costs more  than a small choke mikuni or Mk1 concentric and I have tried that with other carbs. I bought a new TT carb for my race bike and could not belive the improvement over what I thought was a well maintained old one
these small 'dougie' amals include push down chokes they always stick up nowadays after a few days of non use. if I used the douglas every day i could live with it, constant  use frees the surfaces and keeps the jets clean and the fibre washers in good condition.If it was a display bike I could live with it but using it once or twice a month for decent runs is the worst of both worlds

Offline eddie

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Re: Sacrilege!
« Reply #3 on: 12 Aug 2013 at 06:58 »
"World Wide" also includes countries where ethanol is included in the fuel, and owners seem to be coping quite well. OK, unleaded is not as good as the old 4 star, but with a few adjustments doesn't cause too many problems. Using unleaded, I found my postwar Dougs tended to run a little on the weak side, so I've gone for one size smaller on the slide cutaway and an increase of 5 - 10 on the main jet - then drop the needle one notch to compensate. With these settings, the pickup from tickover is good and sustained full throttle gives a good colour reading on the plugs.
   The problem of 'gummed up' jets will not go away by changing to another make of carb - it is caused by the extended idle periods between rides. I make a point of turning off the fuel after each run and letting the engine burn off the remaining fuel in the carbs, so that there is less to congeal in the float bowls and jets.
    With regard to the choke slides - they never were much good, and are best ignored - with the carbs correctly set up, a couple of prods on the ticklers should give the necessary enrichment for reliable cold starts.

  Eddie.