Monobloc carbs and modern fuels
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Monobloc carbs and modern fuels
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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Re: Monobloc carbs and modern fuels
I,ve never found the need to change the settings on any of my ( Amal carbed ) bikes, despite all the hype.
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Re: Monobloc carbs and modern fuels
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
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
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Re: Monobloc carbs and modern fuels
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
Malc
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Re: Monobloc carbs and modern fuels
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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Re: Monobloc carbs and modern fuels
All mine are bog standard as per book with no issues at all.
Colin
Colin
only dead fish go with the flow
- Rob Harknett
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Re: Monobloc carbs and modern fuels
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.
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Re: Monobloc carbs and modern fuels
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.
Good riding to everyone.
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Re: Monobloc carbs and modern fuels
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
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
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Re: Monobloc carbs and modern fuels
Hi Ian
Thanks for the tip about the free Amal catalogue, I wasn't aware of this when I ordered my carb
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
Thanks for the tip about the free Amal catalogue, I wasn't aware of this when I ordered my carb
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