Monobloc carbs and modern fuels

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LynP
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Monobloc carbs and modern fuels

Post by LynP »

Hi, I am interested in peoples experiences on modern fuels and the set up of monobloc carbs. My engine is a 350cc heavyweight with monobloc carb, both engine and carb in good standard condition and air filter fitted. I am using set up as described in the factory owners manual with air filter (pancake air filter with paper element in my case}. My question is, has anyone found the need to change any settings for the fuels we use now?
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1608
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Re: Monobloc carbs and modern fuels

Post by 1608 »

I,ve never found the need to change the settings on any of my ( Amal carbed ) bikes, despite all the hype.
Mick D
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Re: Monobloc carbs and modern fuels

Post by Mick D »

Hi

I have a new Monobloc jetted as per the original spec - it runs well with a very low tick over, no spitting back, no popping in the exhaust - I have no intention of changing the jetting.

Regards Mick
MalcW
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Re: Monobloc carbs and modern fuels

Post by MalcW »

I have a brand new Monobloc with standard jets and slide cutaway for a bike with no air filter, as supplied by the spares scheme, fitted to my Model 31. No problems at all - tickover and throttle pickup are good, and no spitting or backfiring. Well, unless you count forgetting to retard the magneto before starting...

Malc
SPRIDDLER
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Re: Monobloc carbs and modern fuels

Post by SPRIDDLER »

Bog standard '54 G3LS. Runs fine with Monobloc carb (no air filter) set up as per original Owners Manual. 26,000 miles in 5 years, including Alpine and Pyrenean mountain passes up to 2,400m.
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cbranni
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Re: Monobloc carbs and modern fuels

Post by cbranni »

All mine are bog standard as per book with no issues at all.

Colin
only dead fish go with the flow
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Rob Harknett
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Re: Monobloc carbs and modern fuels

Post by Rob Harknett »

Same here no noticeable change. Only difference from when it was leaded fuel, I put a drop of lead replacement stuff in the petrol tank occasionally.
LynP
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Re: Monobloc carbs and modern fuels

Post by LynP »

Thank you everyone for your help. I will leave things as they are, I needed the reassurance to put my mind at rest.
Good riding to everyone.
g5wqian
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Re: Monobloc carbs and modern fuels

Post by g5wqian »

mine is ok on my model 30 , the only thing that can happen on a slightly older monobloc is if it uses and older version plastic float which may expand in the float bowl and go tight , due to the E5 ethanol based petrol .

the new floats are ethanol proof im told .

as for settings , well its just a case of setting carb adjustments to suit your engine and location/altitude and they have enough range to facilitate most if not all .

i get the odd backfire , but i am not running on the rich side at all , my dad said a backfire is good once in a while to clean the carb out , so i will go with that .

float needle seems fine whichever type i use whether nylon or tipped , obviously the new ones are ethanol proof and cheap to replace .

amal uk have all you need to keep going , i think they will give a club discount if you add a message along with an order and its 5% off the price .

my mate works there and i get a discount but i remember them replying saying they had given me the club discount , it isnt a huge amount but if buying a new carb or a few bits and bobs it can pay the postage cost.

they will send customers one copy of the amal catalogue free of charge on application and it is a bound book not a bit of paper .


at least we can still get bits and new carbs thanks to those keeping the businesses going .

cheers
ian
Mick D
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Re: Monobloc carbs and modern fuels

Post by Mick D »

Hi Ian

Thanks for the tip about the free Amal catalogue, I wasn't aware of this when I ordered my carb :roll:

Got in touch with Burlen this morning and asked if there is a facility to download a PDF from their website as I couldn't find one, got an almost immediate response with a PDF version attached, (29Mb).

I have permission from Burlen to upload the file to the Club's website, (rather than have Burlen getting multiple request from Club members), - if the committee feel this would be beneficial please get in touch to advise me as to how best to do this.

Regards Mick
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