Author Topic: Carburetor set up  (Read 310 times)

Offline TT John

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Carburetor set up
« on: 26.02. 2019 09:55 »
Hello,
I have just changed the carburetor on my A7, I have fitted a PWK flat slide, which seems to be fine on start up and running up to about 50-60 mph but then flats out, anyone know what jets should be fitted? this one had a 115 main I feel sure it should be a lot higher, I am going to try a 150 in it today but if anyone has any experience in these carbs or advice as to which the correct jet size should be for this bike, I  would welcome this.

Regards TTJohn

Offline Steverat

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Re: Carburetor set up
« Reply #1 on: 26.02. 2019 17:15 »
I have used a PWK carb in a Tiger Cub rebuild, it worked very well and was cheap, but the supplier could not send me any alternative jets. Perhaps a Mikuni stockist can help, I think the PWK may be an (extremely?) similar design.

1951 BSA A10 - now returned to Germany
1972 Triumph T100R Daytona
1924 B-S SS80
1965 Triumph SH Cub
1960 AJS M18CS

Offline A10 JWO

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Re: Carburetor set up
« Reply #2 on: 26.02. 2019 17:59 »
Think they are like the OKO Carb used on Italian 2 Strokes, jets are easy to get. Look at Lambretta Carbs on ebay ( I did say Lambretta ) Don't Boo please.

Online muskrat

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Re: Carburetor set up
« Reply #3 on: 26.02. 2019 20:08 »
G'day TT.
Their a copy of the Keihin carb same as the OKO. I have two on my A10 Cafe. I thought they came std with a 130 main. I just got a couple of cheap repair kits https://tinyurl.com/y5rzpwca I'll check the size later.
Cheers
'51 A7 plunger, '57 A7SS now A10CR, '76 XT500, '77 AG175 '83 CB1100F, '81 CB900F project.
Australia
Muskys Plunger A7

Offline TT John

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Re: Carburetor set up
« Reply #4 on: 26.02. 2019 22:43 »
Hello Muskrat

I did get a set of jets, I think about ten in a pack from the land of the rising sun, I am just having to try the different size jets. they seem to be very good carbs for the money.

Thanks for the advice

Offline olev

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Re: Carburetor set up
« Reply #5 on: 27.02. 2019 08:46 »
Gday John,

When you get it running sweet, please let us know your carb settings.
cheers

Online muskrat

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Re: Carburetor set up
« Reply #6 on: 27.02. 2019 19:04 »
G'day John.
The biggest hurdle with these carbs are the needles. They control 1/4 to 3/4 throttle. They come in different thickness, length and taper that work on different throttle settings. https://tinyurl.com/ycsvynwo
If the carb came with a 115 main the needle may be way out as well.
Try lifting the needle a notch at a time.
Cheers
'51 A7 plunger, '57 A7SS now A10CR, '76 XT500, '77 AG175 '83 CB1100F, '81 CB900F project.
Australia
Muskys Plunger A7

Online Slymo

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Re: Carburetor set up
« Reply #7 on: 20.04. 2019 01:51 »
Surely at 55-60mph it will be a main jet issue? I'd suggest a plug chop after a fast run and see what colour they are.
NZ