1974 850 Roadster: Amal Premier Carbs? (2018)

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Back to basics, maybe? The float levels may require a look and some measurement, but you haven't said a word, in your most recent post, about syncing the slides. Start with the easy stuff first, drill down if you need to.

All to often over complicating a malady leads to creating new issues, I'm was as guilty of this as the worst offender; then I got lazy, saved me from rebuilding the Norton every time it did something I didn't like...
 
I ordered the Premiers yesterday (Saturday) from CBS. Sent an email ahead of time to see if #19 pilot jets could be swapped for the 17's--no problem at all, and carbs shipped within an hour or so of the order (No additional charge for the jet swap).:):) I will do as others here have suggested to take the carbs down and verify component specs, float levels, and check drillways for swarf and other foreign material--just to be on the safe side. :cool:


Thanks!

~998cc
Quoting myself here. Installed the carbs today, but beforehand, took them down and and checked everything and did find a little brass dust in the drill ways. The floats were right at flush with the top of the bowl, so I did adjust them slightly below the bowl. The pilots are 19's' others are 106, 260 and 3-1/2 slides. The needle was set in the bottom slot, so I set to the middle.
Fired the bike up and had the carbs adjusted in 5 minutes. The idle is low rpm and is very very smooth--amazing.
Put about 5 miles on it a few minutes ago. The engine is noticeably smoother than with the old 932's.
One odd note. The pilot jet on one carb runs best just recessed from the carb body while the other is just proud of the carb body. I will try again from scratch to see if the results are the same.
~998cc
 
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998cc
Glad it,s worked out well for you, took a little bit of tweaking to get mine right.
Adjust each mixture screw individually to where each cylinder runs best at your chosen idle speed, which means the screws will probably be at different settings unless you,re lucky.
Also putting your hand on the rear sides of the silencers at idle should reveal similar temperatures if the mixture and synch are correct.

This is what the Old Timers have suggested for years along with rods in the carbs to synch and they,re dead right, surprisingly accurate.
I don,t even bother using my vac gauges any more and the bike runs sweet as.
 
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When checking the 932's on the bike, the float level was way high on the right carb. Adjustment of the seats came to mind, but the float pivot pins in both carbs were held in place by peening/staking the slot to grip the pin. Wanting to avoid doing any damage attempting to remove the pins, I left them as-is. The carbs were inspected, components noted, cleaned and reassembled--high float level and all. I may take another look at them after the new carbs are checked, adjusted if necessary and installed.

Thanks!
~998cc
The ancient float bowls are shot and leaking internally. Get new stay-ups. Get new float needles , the latest type.. Spend.
 
Would the tickler protruding deeper into one carb body make any difference?Mine is.
 
Would the tickler protruding deeper into one carb body make any difference?Mine is.

Probably not. If it were making a difference , that difference would express itself, in all likelihood, as a leak. I would be bothered by the difference, as well and would be inclined to see if the vendor I purchased the carb from would exchange it, or repair it. Or, in my case, do the learning, ask the questions then fix it myself; the maximum tuition is just another carb, much less then even one credit from a community college...

I have no experience replacing the tickler parts, but many on this forum do; it is entirely possible that the difference can be easily remedied, but I can't say.
 
Spraying WD-40/carb cleaner around the manifold/carbs at idle would be an easy test of vacuum leaks.
 
998cc
Glad it,s worked out well for you, took a little bit of tweaking to get mine right.
Adjust each mixture screw individually to where each cylinder runs best at your chosen idle speed, which means the screws will probably be at different settings unless you,re lucky.
Also putting your hand on the rear sides of the silencers at idle should reveal similar temperatures if the mixture and synch are correct.

This is what the Old Timers have suggested for years along with rods in the carbs to synch and they,re dead right, surprisingly accurate.
I don,t even bother using my vac gauges any more and the bike runs sweet as.

KiwiNeill, I started with carefully adjusting the throttle cable adjusters resulting in the slides closing at the same time. Then set each mixture screw at 1-1/2 turns out. Started the bike and adjusted the throttle stops to get a reasonable idle. Adjusted the mixture screws to achieve a better idle. Finally, adjusted stop screws again to idle mainly on one side, readjusted that side's air screw for best idle then turned in 1/4 turn. Repeat on the other side then adjusted the throttle stops for an even but easy loping idle. I have the balanced exhaust currently which hampers using it for much in the way of determining cylinder health on either side. Couldn't use the rods due to the difficulty of removing the K&N air filter--listened for clicks of the slides instead. It may be the wrong way to sync carbs but it works reasonably well for me. :)

I had a set of "Carb Stix" in the 1970's that used mercury as the indicator. Tried to use them on my KZ-1000 Kawi, and couldn't makes heads or tails out of the pulsing in each stick--never used them again.

~998cc
 
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The ancient float bowls are shot and leaking internally. Get new stay-ups. Get new float needles , the latest type.. Spend.

Got new Premier Amals which include the stay ups. So far, so good! :)

~998cc
 
998cc
Can,t fault that proceedure and it works for you, I think you,ll be well pleased with the Premiers.
Forgot to mention re the velocity stacks, makes the rod synch method trickier, that,s why I made up a set of vac gauges.
Click test better for those not affected by long term industrial hearing loss or not wearing earplugs while riding over the years..
I also got a four cylinder set of Carbtune column type but with stainless plugs rather than mercury. Never worked as good as adjustable cheap vac gauges, so still in the cupboard.

Speaking of your Kawa, doing up a '78 KZ1000 D1 engine next, 1075 kit with all the nice hot rod bits, brmm, brmm.
 
998cc
Can,t fault that proceedure and it works for you, I think you,ll be well pleased with the Premiers.
Forgot to mention re the velocity stacks, makes the rod synch method trickier, that,s why I made up a set of vac gauges.
Click test better for those not affected by long term industrial hearing loss or not wearing earplugs while riding over the years..
I also got a four cylinder set of Carbtune column type but with stainless plugs rather than mercury. Never worked as good as adjustable cheap vac gauges, so still in the cupboard.

Speaking of your Kawa, doing up a '78 KZ1000 D1 engine next, 1075 kit with all the nice hot rod bits, brmm, brmm.

KiwiNeill, won't venture off topic here, but I can relate to hearing as I am nearly deaf in my right ear and have about 70% in my left ear with limited frequency spectrum. Can still hear the slides click in my closed garage. Always wear earplugs on the bike now.

Kawi: '77 KZ-1000. Bought it new in Dec. '76. It buzzed the bars above 4000 rpm and was intolerable at/near 5000, so I sold it in 1978 and bought a Vincent! :eek:

~998cc
 
I practically rebuilt my motor chasing this problem having checked the new premiers had the right jets and needles in the first instance. Finally I found that although the needles were marked up both correctly, one had a slightly different taper than the other when compared side by side. Put a needle in out of my old carbs, problem solved. Quality control my arse!
That's scary. Never throw away anything.
 
Quoting myself here. Installed the carbs today, but beforehand, took them down and and checked everything and did find a little brass dust in the drill ways. The floats were right at flush with the top of the bowl, so I did adjust them slightly below the bowl. The pilots are 19's' others are 106, 260 and 3-1/2 slides. The needle was set in the bottom slot, so I set to the middle.
Fired the bike up and had the carbs adjusted in 5 minutes. The idle is low rpm and is very very smooth--amazing.
Put about 5 miles on it a few minutes ago. The engine is noticeably smoother than with the old 932's.
One odd note. The pilot jet on one carb runs best just recessed from the carb body while the other is just proud of the carb body. I will try again from scratch to see if the results are the same.
~998cc

So, I’ve decided to put these carbs on my 850. Does anyone know where I can source them in the US with the specs shown above? Thanks.
 
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