a question of carbs

Whitworth Ranch said:

I recently replaced my sleeved original Amal 32s with a pair of new Premiers. Unfortunately, I ordered 30s, but decided to use them anyway. I have to say I am very pleased with how the bike runs and its response to tuning changes. The Premiers seem to behave a lot more like "instruments" as compared to the originals. Of course, the old ones had about 13,000 miles of use and had warped and been machined/sleeved. But I was never happy with the post-sleeve clearance.

Still thinking about trying those JS flat-slides at some point.
Mark

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You could sell them to those Triumph people. They need the little carbs. :mrgreen:

swooshdave said:

Whitworth Ranch said:

I recently replaced my sleeved original Amal 32s with a pair of new Premiers. Unfortunately, I ordered 30s, but decided to use them anyway. I have to say I am very pleased with how the bike runs and its response to tuning changes. The Premiers seem to behave a lot more like "instruments" as compared to the originals. Of course, the old ones had about 13,000 miles of use and had warped and been machined/sleeved. But I was never happy with the post-sleeve clearance.

Still thinking about trying those JS flat-slides at some point.
Mark

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You could sell them to those Triumph people. They need the little carbs. :mrgreen:

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That's funny... Actually, a friend of mine with a '68 Fastback said he'd like them when my 32s come in.

I have a pair of sleeved amal 932's on my late 72' roadster and have no complaints with them, bike fires up easily and the carbs have given me no problems in three years and about 13,000 miles.

A fellow I ride with has an 850 with a single Mikuni. I can out accelerate him by a slim margin with my bike. He does appear to get slightly better fuel mileage when we ride together, about 10-15% less in his fill ups than me for equivalent distance ridden. I have no idea if the fuel savings is related to the single carb, or the nature of 850s vs. 750s, or if his bike is in a different state of tune...

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northern750 said:

I have a pair of sleeved amal 932's on my late 72' roadster and have no complaints with them, bike fires up easily and the carbs have given me no problems in three years and about 13,000 miles.

A fellow I ride with has an 850 with a single Mikuni. I can out accelerate him by a slim margin with my bike. He does appear to get slightly better fuel mileage when we ride together, about 10-15% less in his fill ups than me for equivalent distance ridden. I have no idea if the fuel savings is related to the single carb, or the nature of 850s vs. 750s, or if his bike is in a different state of tune...

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I beleive even if you switched the single carb to the '72 combat and twin Amals to the 850, the 750 would still have some advantage accelerating. That said it's a crime to put a single carb on a combat engine.

I beleive even if you switched the single carb to the '72 combat and twin Amals to the 850, the 750 would still have some advantage accelerating. That said it's a crime to put a single carb on a combat engine.[/quote]


FWIW, my 750 is one of the late 72' 'detuned' 750s with a low compression head, so it's not a Combat, but I have no intention of removing the 932s from it. But I agree, a Combat with a single Mikuni is a bit unnatural.

If you still have the original MK I set of carbs, then the cheapest option is sleeving the pair and that should result in a completely acceptable set up. If you want more power for not much more money, then get Jim's flatslides or, for a "keep it British" Amal upgrade, go for those MK IIs.

northern750 said:

I beleive even if you switched the single carb to the '72 combat and twin Amals to the 850, the 750 would still have some advantage accelerating. That said it's a crime to put a single carb on a combat engine.

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FWIW, my 750 is one of the late 72' 'detuned' 750s with a low compression head, so it's not a Combat, but I have no intention of removing the 932s from it. But I agree, a Combat with a single Mikuni is a bit unnatural.[/quote]

Again, I have to take issue with this opinion: My Combat with it's TM34 Mikuni flat slide is a screaming fast machine. 75% of my riding is moderately fast to very fast. I regularly keep up with my bud's on their Ducatis and Thruxtons when blasing around the hills and twisties of central Florida. My Nortoneering buddy on his "tricked out" 850 with dual Amals is regularly looking at my tail lights. Aesthetically, yes , the single Mikuni is not a dual carb setup....but I got over that a long time ago. IMO, I feel the touble-free reliability, 1st kick starting, "set and forget" performance outweighs the aesthetics. Also, it seems strange to me to see overwhelming acceptance of the JS flatslide carbs when the Mikuni "look" is criticized as not looking natural (e.i., not stock). I appreciate the stated performance reports about the JS carbs...I would love to try them, but $$$ these days makes me stay where I am....and think they're a great option if anyone wants to replace their Anals....but has anyone taken a real good look at them...they look like Mikuni styled carbs to me!

cmessenk said:

northern750 said:

I beleive even if you switched the single carb to the '72 combat and twin Amals to the 850, the 750 would still have some advantage accelerating. That said it's a crime to put a single carb on a combat engine.

Click to expand...

FWIW, my 750 is one of the late 72' 'detuned' 750s with a low compression head, so it's not a Combat, but I have no intention of removing the 932s from it. But I agree, a Combat with a single Mikuni is a bit unnatural.

Click to expand...

Again, I have to take issue with this opinion: My Combat with it's TM34 Mikuni flat slide is a screaming fast machine. 75% of my riding is moderately fast to very fast. I regularly keep up with my bud's on their Ducatis and Thruxtons when blasing around the hills and twisties of central Florida. My Nortoneering buddy on his "tricked out" 850 with dual Amals is regularly looking at my tail lights. Aesthetically, yes , the single Mikuni is not a dual carb setup....but I got over that a long time ago. IMO, I feel the touble-free reliability, 1st kick starting, "set and forget" performance outweighs the aesthetics. Also, it seems strange to me to see overwhelming acceptance of the JS flatslide carbs when the Mikuni "look" is criticized as not looking natural (e.i., not stock). I appreciate the stated performance reports about the JS carbs...I would love to try them, but $$$ these days makes me stay where I am....and think they're a great option if anyone wants to replace their Anals....but has anyone taken a real good look at them...they look like Mikuni styled carbs to me![/quote]


I am not judging anyone else's choices, just stating my own opinion. The guys I know who've gone the single carb route are all happy with their choice, the improved fuel economy has especially been welcome in my part of the world where gas stations are often 80-100miles apart. Anyway, I've got my resleeved Amals tuned so the bike is a one or two kick starter hot or cold and I like the look of them. To each their own.

I have always been a Amals man and sweer by them but since putting Jims flatslide carbies on, man what a big diffrents they have made to the performance of my Norton and when you crack open the throttle the hardest part is keeping the front wheel on the road :twisted: so the Amals will just sit in the shed for a very long time I think and I have had a very good run with my amals well over 80,000 miles.

Ashley