Still not easy to start, must be the carbies??

Not open for further replies.
Dec 5, 2007
Hi guys i have fitted Pazon ignition to my 1970 750s and timed and all seems good but it is still hard to start. I flood the carbies with the ticklers, which seems to take 30 seconds not just a few tickles. two kicks with out key on to prime it,turn key, full kick it fires a few times,then i have to reflood it fires a few times again, do this four or five times it will start, once hot its a one kick.It runs fine when riding. I,m sure the primary jets are clear and i dont think its leaking air and the float levels seem ok. I was thinking i should renew all the jets/gaskets ,needles ,etc. to eliminate that as a cause. Can anyone point me to a complete refurb kit for Amal 930/30 s please. Cheers
You need to search the site for the Bushman's link, good pictures of the insides with cutaways. You need a #78 drill bit glued into the end of a spray tube and you need to reset your floats , cables , and air screws. Rebuild kits naw, just some fresh nettle jets dude. Do searches using these as key words you will sort it fast.
LAB directed me to the bushmans site which is very helpful. Ive used a welding tip cleaner equivelent to that size drill bit. I cant see in there as i am probing but it feels to be going thru to the mixing chamber easily and no gunk. Does anyone now the distance the drill bit will travel to fully be in, maybe measured from the outside face of the screw hole? My eyes arent up to the mark for such delicate stuff i am afraid

Rockyrob said:
I,m sure the primary jets are clear and i dont think its leaking air and the float levels seem ok. I was thinking i should renew all the jets/gaskets ,needles ,etc. to eliminate that as a cause. Can anyone point me to a complete refurb kit for Amal 930/30 s please. Cheers


If you haven't already, a standard rebuild of your Amals may be in order. There's several other issues that might be relevant, but I'll focus on the carbs (briefly) here. And don't rule out that you may have an air leak at the carb-to-manifold connection (know you said you didn't think it was an air leak, but these can be tricky to discern). By the way, the large O-ring required for that seal does not come in the Amal rebuild kit....

Regarding rebuild kits:

Don't rule out a basic, pedestrian Ebay supplier of parts (not affiliated in any way, just suggesting a possible option for finding the kit at a reasonable price):

Good luck!

You gave a few clues doesn't tickle easy, runs right out of gas needs more tickle. Some things to look at:Floats are not set right or or the ticklers are not set right ( they don't go down far enough because the pins have slipped up into the button that you touch) easy fix. The tank is not breathing. Or you have rubber lined petcocks and the rubber has swelled shut. You have a hot cam no dynamic compression at kicking speed therefore low vacuum, any little air leak makes it hard to start. It is a hot rod of sorts.
Glad you made an attempt to clean the idle jets but I think I got it don't work here. Get the drill and glue it into a thin tube you will than you will feel if it's clean and tight or if it has been drilled out by someone before you. You have to know. It's a good thing to do once a year for the tune up. It's a .016 hole your motor starts and idles on. If it's not clear the air screws won't respond to adjustments. You can buy the kits to rebuild the carbs but with some O-ring grease and some sand paper I could make it work.
One more little thing if you have a cable hanging up and it has the carbs out of sync or even one slide pulled up a little your done. Most carb problems are electrical.

Have you tried flooding with both taps open and have you tried the choke? Also check the carb fuel filters. How about cold and or dirty plugs, have you tried a hotter grade or new plugs? Fouled plugs can give the same problem
You can't be far away if the bike runs well hot.

Rockyrob said:
I flood the carbies with the ticklers, which seems to take 30 seconds not just a few tickles.

If there is a reasonable fuel flow coming from the tank then the tickler pins may have been pushed too far into their buttons as norbsa suggests?

If the fuel is turned on and allowed 10-20 seconds or so for the float chambers to fill to their normal level, pressing (and holding) the ticklers should then result in fuel dripping from the carbs in about 3-5 seconds.

Some people tend to 'pump' ticklers, maybe they think they are gaining something by doing that? But as I see it, each time the tickler button is released then the flow of fuel is being interrupted, so would actually slow the flooding process down.
Thanks for the suggestions guys, plugs are new as recommended , air screws when adjusted make a difference so i assume the pilots are clear but i will put a drilll thru them to make sure, i will recheck the float bowls and the ticklers to make sure they are working properly, as it takes way more than three to five seconds to flood the carbies, i dont think fuel tank or suplly lines are an issue as once its running its all good, the carbies are not running out of fuel its just getting enuff fuel into the chambers to get it running i think, the air leak is looking more like a culprit i think its lean trying to start so i will check that also, your ideas and suggestins are greatly appreciated thanks

If you have an air leak it would show its self when the motor is hot a lot worse than when it's as rich as hell on cold startup.

Do you have the choke slides fitted? If you haven't that's your problem. Amal fitted them for a reason.

Chokes are still fitted altho i never use them. I live in a subtropical climate and its summer here, Lowest temp we would ever get would be 10/15 deg C and if its that cols i aint going riding lol
For about 75.00 each you can get the old ones reworked. From what I have heard it's a better option. As long as the idle jets are still a good tight .016 hole and the cavity at the 90 degree bend is not filled with gunk.
One day you will get totally frustrated with those Amal's and do the right thing . Buy a single Mikuni :D

I fought for 7 years with Amal's. Two years ago i put a 36mm Mikuni on and right out of the box it worked just fine and have never had the need to make any adjustments what so ever.
hopefully it wont come to that. the bikes ive seen converted seem to have a big hole where something (twin carbs) is missing. I like the original look but i certainly hear you.

Hard to start, needs a lot of flooding, but runs well when hot?? How old's the petrol in the carbs? Could be the volatiles have gone from a float bowl left full, floofing gets more new gas in. When hot, not a problem as the gas is fresh. Modern no-lead seems to be a lot worse for this, not sure if ethanol also makes it even more worse... Try draining the bowls then re-tickling? Just a thought before stripping or replacing carbs.
If the carbs are running well hot there's nothing much wrong with them don't start spending just yet. What happens when you try the chokes?

I'd have another think about norbsa's comment " Most carb problems are electrical." - I was having 'idle problems' with my roadster, and spent quite a while tracing air leaks, synching carbs, adjusting mixtures etc, but at the weekend i replaced one of the coils & lo & behold the darn thing started behaving :!: Mind you it now has a pair of the best (or most) synchronised and adjusted Amals in the northern hemisphere! :lol:
You're in danger of getting in to a loop. If you reset the float levels you will have a effect on the hot running of the carbs, and perhaps not a good one. With reference to the tickler level, once fuel is pouring over your finger it isn't going to get any higher.
Try chokes full on, flooding, a little throttle, ignition on and kick it in to life. Try little or more throttle to you find the sweet spot. That's all I ever do with Mk1 Amals.

Not open for further replies.