Author Topic: gidday and carbs  (Read 3382 times)

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Offline flea

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gidday and carbs
« on: 01 Sep 2018 at 22:34 »
this just to say gidday and thanks for letting me join , just bought a T35 1947/48 350cc , have had nothing to do with the douglas before, in fact the earliest bikes iv had are the 1951 ajs 500 and a 1951 bantam (yr of my birth, so may be a common theme) 1947 is the yr my brother doug was born..lol . left late sun night to pick it up and arrived home thur morn at dawn after traveling 3600 kls all up...(needless to say I was knacked after the drive , no other driver or passenger)..the t35 is in very good order as a older restoration with the only prob being the carbs and tyres , 1 carb leaks badly , my guess is carbs fairly well worn out  NOW I KNOW some members will object to the idea but I want to put some more modern carbs on .. jap , chinesse, European etc , iv heard its been done before with a good increase in power and reliability so can some one point me in the right direction as to what carbs/jets etc etc were used was ,also think if possible will add a bent inlet manifold as this may allow me to use a air filter (country area and I hate no filters just on principle ), tyres naturally will need replacing as fairly old .. plan to be using this locally every now and then , not just for display and the odd rally once a yr... also was the douglas the only british horizontily opposed (boxer style) bike built or was there others

Offline graeme

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Re: gidday and carbs
« Reply #1 on: 02 Sep 2018 at 05:11 »
Can't advise on carbys, though I know plenty will tell you to get the originals refurbished and they're all good.

I do know of other British horizontally opposed twins though, notably ABC and LE Velocettes. Also Coventry Victor, Humber, Williamson, Zenith with oil cooled Bradshaw engine - sure to be others if I put my thinking cap on

Offline flea

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Re: gidday and carbs
« Reply #2 on: 02 Sep 2018 at 22:15 »
ah , that's intresting , will have to look some of these other bikes up , still intrested in some modern carbs though as among the spare parts is a almost complete motor which is missing the carbs and a gearbox casing with a lot of gears etc in a box so rebuilding the spare motor id definitely on the cards.. also out of curiosity would like to see the difference a modern carb would make.. a air filter would be great as im on country rds and hate the thought of running open stacks

Offline Hampshirebiker

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Re: gidday and carbs
« Reply #3 on: 03 Sep 2018 at 10:31 »
Try the search facility Flea. There was a thread on here some time ago. I bought a pair of Chinese carbs that a member recommended very cheap on line. The trouble is that they're spigotted so adaptors have to be made (the shorter the better). I can't find them at the moment, but they may turn up.

New bodies were available through the club and most other bits from the likes of Hitchcocks or Surrey Cycles. Jet blocks aren't available; but can be cleaned. Good luck.

Offline flea

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Re: gidday and carbs
« Reply #4 on: 04 Sep 2018 at 02:43 »
thanks will have to look into the club if those sort of parts are avalible (plus others),saw a post saying a lot of renewibles were avalible through the club but looks like got to join first to find out what parts are there , did find one search but it just said other carbs could be used but needed a adapter... going to have to get a tape out and do some measuring

Offline Hampshirebiker

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Re: gidday and carbs
« Reply #5 on: 12 Sep 2018 at 09:45 »
Another option that I considered was to make a manifold to a single Monobloc; similar to the Dragonfly principle. From memory, it may need the regulator to be relocated. I wonder if anyone has tried this method.

Offline eddie

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Re: gidday and carbs
« Reply #6 on: 12 Sep 2018 at 11:10 »
That would probably cause more problems than it solved. Under certain conditions, Dragonflies are very prone to carburettor icing - even with the inlet manifold cast into the gearbox bellhousing (to gain a little warmth).

  Eddie.

Offline Hampshirebiker

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Re: gidday and carbs
« Reply #7 on: 12 Sep 2018 at 14:00 »
I was aware of that Eddie and remember your story of the A3 at Durford Wood. Australia may not be so hazardous.

Offline flea

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Re: gidday and carbs
« Reply #8 on: 12 Sep 2018 at 21:41 »
when you say single block , is that doing a 2-1 carb system , doing simmiler to my xs650 at the moment , and yes it doesn't get as cold here in oz EXCEPT in a few places .even though im in the tropics because of altitude it still gets mminus 2-4-5 deg c a few times ea winter so the manifolds icing shouldnt be to much of a prob , have applied for the douglas club, didn't know there was so many parts avalible , will be intresting to see the list

Offline eddie

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Re: gidday and carbs
« Reply #9 on: 13 Sep 2018 at 06:18 »
Carburettor icing doesn't necessarily happen in low temperatures - it seems more dependant on the humidity.

  Eddie.