Hitchcocks Forum

Yesterday I fitted the EFI to Amal Mk 1 carb conversion kit. I found the installation straight forward with all the components fitting together very well and providing exactly the look I desired. However... the bike will only run with the choke ON (the air slide down, choke lever NOT under tension) and I can't seem to tickle the carb...no petrol comes out
Tick-over is even, revs from idle reasonably cleanly and falls back to stable tick-over but the engine dies immediately when attempting to turn off the choke
Where should I start? I'm guessing the float height is too low and the engine starved of fuel but I'm reluctant to tear apart a brand new carb without your advice!

Regards Emma

First check petrol is actually coming out the tap.mine was barely a dribble.
I replace the obviously very cheap tap with a better quality push pull type tap and have no problems now.

Obviously something basically wrong there.

First thing I did with my Wassell (AMAL copy) 26mm concentric carb was to strip it down. With all the trouble I'd had with the Mikcarb I wanted to check it was OK before I fitted it. It was straightforward and I just left the original float bowl gasket in place.

After trying it on the bike (and buying a cable and lever) I soon discarded the choke mechanism completely and blanked off the cable fitting point. Two reasons, firstly because I soon discovered my bike doesn't need it and with the screen mounts I didn't have enough space on the handlebars to comfortably mount the lever.

Thanks for the reply Haggis...I agree the pet tap flow is without merit but it supplied enough gas to get me across town at upto 40mph and would surely provide enough lift to raise the float to its maximum height. For future reference what pet cock would you recommend that fits the adaptor plate supplied with the conversion kit.

Emma

Im afraid Amal have a bit of a reputation for leaving all sorts of swarf in brand new kit.

I bought a push/ pull tap with reserve but seems to be no longer available.
There I one without a reserve available though.
This the one I have, 36583, https://accessories.hitchcocksmotorcycles.com/5747
I must admit, apart from the tap, work absolutely fine straight out the box.

The flow through my tap wasn’t brilliant either, but there was also an issue with an airlock because I fitted a clear fuel pipe that was too long. Replacing it with a better, proper black fuel hose sorted it for me. I know of another guy who had to replace his supplied tap too. I don’t know why Hitchcocks don’t supply a decent one.

Both the MK1 amals I've had will periodically refuse to tickle for no apparent good reason. (one normal, one premiere). Still no idea why. The one on my 612 did it just the other day.

My current theory is that the needle valve may be sticking up in its seat if it was parked up with a full float bowl. I'm going to start turning off the fuel at the 30mph signs as I come into my village and see if that stops it. I already have a half decent OMG fuel tap fitted.

When it comes to “tickling”, my concentric carb is very sensitive to float height.
I like to know how many seconds a full tickle takes so I can do it by feel. I lowered the float height very slightly from the factory setting and the time it took for a dribble of fuel to appear was doubled from five to over ten seconds. I know some owners believe that the tickler should repeatedly pressed and released but my interpretation is one long push.

I have a clear fuel line so you can see if the tickler is doing anything.