Forum

[Adrian]

Depending on where they're sourced these carbs can be ludicrously cheap. I paid £17.something including postage for a 34mm version last year, at that price you can probably afford to experiment.

A.

[Presto]

£17 for a carb – and people complain about the QC on Mikcarbs!!!

[jawa-enfield]

Your idle jet is a bit bigger than normal but thats only at idle and 1/4 throttle. You need to lower the needle jet and see if that helps. Jetting an unkown carburettor is not easy.

That does not help, it even chokes on a 100 main jet. There is with these carbs, a seller told me, no difference in 2- or 4 stroke versions. Normally they are used solely on 2-stokes..

[jawa-enfield]

i paid 90 euro for the polini pwk, wanted to be sure of some quality.Float level is hard to check but seems okay(the thing is brand new!)
It does not overflow.

[Presto]

The misgivings about these carbs seems to be increasing.

If they are sold as suitable for 4 strokes though mostly used on two strokes then there is an anomaly.
This implies that they are set up for 2 stroke engines and those settings in almost every case would not be suitable for a Bullet engine. They would run rich.

Or maybe these are unique in being a 'one size fits all'??!!

[stinkwheel]

Which type of air filter did you use?

Maybe the Wassell is better quality than the original AMAL.

S&B pod filter as recommended by our hosts.

[Adrian]

The misgivings about these carbs seems to be increasing.

If they are sold as suitable for 4 strokes though mostly used on two strokes then there is an anomaly.
This implies that they are set up for 2 stroke engines and those settings in almost every case would not be suitable for a Bullet engine. They would run rich.

Or maybe these are unique in being a 'one size fits all'??!!

As I mentioned earlier there is a specialist retailer in the UK selling PWKs for classic four stroke single and twin use.

In the USA the previous RE importer had a kit specifically tailored to the pre-EFI Bullet, and Steadfast Cycle in the USA still sell them for classic bike use.

I have heard anecdotal evidence of people trying even the cheaper ones on old 4 stroke bikes and needing very little by way of modification to get them running sweetly.

A.

[Cranky]

The only difference between a 2 stroke carb and a 4 stroke carb is the needle jet. The 4 stroke is higher in the throat and has sometimes a shroud. The Needle jet may also have quite a few emulsion bleed holes where as the 4 stroke has one.

This is because the 2 stroke if mixed with oil has a different viscosity but if the oil is injected to carbs are the same.

Setting up a Carb ' out of the box' is pretty well much a specialist job. Our host does not want to set the float level as it is hard to do and it is new. This the first thing you do, ---Where do you go from here then.

[Adrian]

Our hosts Mikarb notes cover float height setting.

https://accessories.hitchcocksmotorcycl ... 1&_xt=.pdf

The Amal notes cover float height checking to, though changing it with the Amal float is apparently a bit of a lost cause, replacement required.

https://accessories.hitchcocksmotorcycl ... 4&_xt=.pdf

As for the PWKs, I'm sure the internet will oblige.

https://jrcengineering.com/wp-content/u ... -Guide.pdf

A.

[dalgrae]

Hi I managed to find a clear float cover to suit a Monoblock carb and on fitting it confirmed that the float height was spot on ,best £3 I ever spent,takes away all the guess work,as to four stroke and 2 stroke carbs being different,I seem to remember on the later Bantams ie D14 and B175 that Amal recommended that the 4 stroke version be fitted .

Colin