Author Topic: Modern carbs  (Read 3622 times)

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Offline dragonmk5

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Modern carbs
« on: 11 Jul 2014 at 18:35 »
Am reluctantly considering replacing my badly worn  Amals with modern equivalents and would be interested in hearing from anyone who has already done this, together with size of carb used. So far I've looked at Mikuni, Dellorto and Wassel.

Offline ian scott

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Re: Modern carbs
« Reply #1 on: 12 Jul 2014 at 12:52 »
Maybe you can find a brand new Amal model that is similar to your worn out ones? http://amalcarb.co.uk

Offline tck

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Re: Modern carbs
« Reply #2 on: 13 Jul 2014 at 18:19 »
Assuming from your logon name you are talking MK5 -T35 etc
You wont find an amal, Burlen dont want to know about small bore carbs
I think a small VM Mikuni would be the best choice
Allens will have a go at setting one up for a 175 four stroke
but even cheaper are copy ones on e-bay and tune it yourself
last time I muted this on the forum I was castigated for thinking of such sacrilidge
well I just put a 28mm VM on my Vincent single and it never went so well -(including an Amal  TT)
its not as if the worn out jokes are in the bin is it?
better to use it thannot fully enjoy the bike via a worn out performance

Offline dragonmk5

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Re: Modern carbs
« Reply #3 on: 14 Jul 2014 at 08:04 »
tck : Thanks for the benefit of your experience with the VM Mikuni carb.  I would imagine you got more stick from the V.O.C than you did on here!  You are, of course, absolutely right - if I change the carbs I won't be chucking the originals out. When I bought the Douglas, it came with a headlight painted blue, sprung saddle and pillion seat, both of which are new, and in order to enable me to ride the bike, which is really too small for me, I have had to fit a dual seat, so I won't be winning any prizes for originality! Hopefully, though, I will have a bike I can use, as opposed to one sitting in the garage.

Offline tck

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Re: Modern carbs
« Reply #4 on: 14 Jul 2014 at 09:51 »
let me know-(all of us) how you get on
Its on my list of jobs to do

Offline dragonmk5

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Re: Modern carbs
« Reply #5 on: 14 Jul 2014 at 18:21 »
Been in touch with a supplier who has stated he may be able to help, but he needs details of jetting requirements. Not sure what to tell him, so will have to look into it.
Will keep you posted. If anyone else has experience of carb swapping, please feel free to chip in!

Offline Ian

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Re: Modern carbs
« Reply #6 on: 15 Jul 2014 at 05:41 »
Not sure why you wouldn't just use new Amal carbs - each to their own. But if you need jetting info I am sure the supplier can just use the Amal settings as a guide. They are on the Amal website

Offline eddie

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Re: Modern carbs
« Reply #7 on: 15 Jul 2014 at 06:05 »
Maybe there is not a lot wrong with the old carbs - they may just need retuning to take into account the fuel we use today is far removed from the pool petrol that the bikes were originally set up to run on. I have found Mark engines run better with a slightly smaller slide cutaway and an increase in main jet by 5 or 10 - and then compensate by dropping the needle a notch or two. There is also a second problem with 'super unleaded' - this tends to have a slightly higher viscosity, so may cause an engine with carburettors to run a bit on the weak side. Fuel injected motors do not suffer in the same way as the injection system pumps a specific amount of fuel on each stroke.

  Regards,
               Eddie.

Offline tck

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Re: Modern carbs
« Reply #8 on: 17 Jul 2014 at 20:32 »
Burlen state on their website Amal 264 and 275 carbs are no longer produced I was under the impression that 15/16" was 274. and that that was what was fitted to the MK5-T35 clan
According to the burlen (Amal) website  the only type made is 276 isnt that an 1-1/16?

More info Ian on what amals are suitable and available

Offline Ian

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Re: Modern carbs
« Reply #9 on: 18 Jul 2014 at 01:05 »
I just did a search on the Amal website and put in Douglas and from memory MK4 Sports

Offline tck

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Re: Modern carbs
« Reply #10 on: 18 Jul 2014 at 12:16 »
Thats right and it will say say type 274 for Mk3 -5 etc but link is only to 274 kit

now goto the pre monoblock page and they say no longer produce type 274 so if you body is bad and mine is its  aresleve at silly prices with someone or a modern carb