BritBike Forum logo
BritBike Sponsor BritBike Sponsor BritBike Sponsor
BritBike Sponsor

BritBike Sponsor

BritBike Sponsor
BritBike Sponsor BritBike Sponsor BritBike Sponsor
JWood Auction JRC Engineering dealers JWood Auction
Home | Sponsors, Newsletter | Regalia | Calendar | Bike Project | BritBike Museum | Spiders Cartoons, "OLD" BritBike Forum | DVD- Manuals & Parts books | BritBike Stickers & Decals
Upgrade to: Premium Membership | Premium Life Membership | Vendor Membership | Site Sponsor Membership
Photo posting tutorial

Member Spotlight
loment11
loment11
Seattle, WA
Posts: 28
Joined: June 2006
Show All Member Profiles 
Shout Box
Search eBay for motorcycle parts in following countries
Australia, Canada, France, Holland, Italy, United Kingdom, USA
Random Gallery photo
Who's Online Now
207 registered members (68 royalstar tony), 1,730 guests, and 592 spiders.
Key: Admin, Global Mod, Mod
Newest Members
David Stothard, iansouthoz, Lightning Sim, Simon.Holyfield, Bushcreature
10036 Registered Users
Top Posters(30 Days)
Lannis 146
kommando 110
Stuart 64
Popular Topics(Views)
478,053 mail-order LSR
Forum Statistics
Forums33
Topics65,736
Posts635,437
Members10,036
Most Online3,995
Feb 13th, 2017
Like BritBike.com on Facebook

Previous Thread
Next Thread
Print Thread
Rate Thread
Page 1 of 2 1 2
Amal float needle: Brass/viton vs. aluminum/viton #425200
03/20/12 2:41 am
03/20/12 2:41 am
Joined: Nov 2005
Posts: 7,259
Back on the mainland!
JubeePrince Online content OP

Life member
JubeePrince  Online Content OP

Life member
Joined: Nov 2005
Posts: 7,259
Back on the mainland!
My set-up: Old-style (not Stay-Up) floats with brass float needles.

I've been reading a few threads here lately that talk about the advantage of the aluminum float needle.

Here's the $64,000 question: Which is better? (I know, too simple a question.)

Is one superior to the other? Anyone have the aluminum ones? Do the aluminum ones really reduce the lean running just off idle?

Thoughts? Experiences?

Discuss...(This is the stuff that I lie in bed thinking about at night. Some say it's a blessing to have such problems, others say it's a curse!)

Cheers,

Steve

Last edited by JubeePrince; 03/21/12 3:20 pm.

'77 T140J
"Vintage Bike". What's in your garage?

"The paying customer is always right."

Fitting round pegs into square holes since 1961...
Support Your #1 BritBike Forum!
Membership Type! Free
Member
Premium
Member
Premium Life
Member
Vendor
Member
Site
Sponsor
Recognition No Premium Member Premium Life member (5 years) Vendor Member Site Sponsor Membership
Post commercial threads No No No Yes Yes
Custom title No Yes Yes Yes Yes
Upload avatar & photos No Yes Yes Yes Yes
Link avatar & photos Yes Yes Yes Yes Yes
Private Message Storage: 10 100 100 100 100
Length of signatures 255 600 600 600 600
Removes this very advert island between post 1&2 No Yes Yes Yes Yes
Price Free $12.90/year $105.00 No End
$55.00/5 years
$210.00/year
($17.50/month)
Email
Click on button >>
  Premium Member Premium Life member Vendor Member Site Sponsor Membership
Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: JubeePrince] #425226
03/20/12 6:52 am
03/20/12 6:52 am
Joined: Apr 2006
Posts: 1,397
New Zealand
J
johnm Offline
BritBike Forum member
johnm  Offline
BritBike Forum member
J
Joined: Apr 2006
Posts: 1,397
New Zealand
Are you sure there is such a thing as a aluminium/viton tip ?

I asked Burlen about this some time ago after seeing an illustration of one on their website. They told me it was a mistake and there is no aluminium/viton tip.

It may possibly have changed because this was about 2 years ago but they definitly told me no back then.

There is an aluminium only needle but this is for alcohol and you do not want to use this because they are very difficult to seal and stop leaking. I have personal experience of this.

Last edited by johnm; 03/20/12 6:53 am.
Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: johnm] #425242
03/20/12 11:32 am
03/20/12 11:32 am
Joined: Aug 2007
Posts: 160
England
P
Paul744 Offline
BritBike Forum member
Paul744  Offline
BritBike Forum member
P
Joined: Aug 2007
Posts: 160
England
Originally Posted By: johnm
Are you sure there is such a thing as a aluminium/viton tip ?

Yes, I've just bought some.

Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: Paul744] #425246
03/20/12 12:03 pm
03/20/12 12:03 pm
Joined: Aug 2001
Posts: 6,742
Vermont
Jon W. Whitley Online content

BritBike Forum member
Jon W. Whitley  Online Content

BritBike Forum member
Joined: Aug 2001
Posts: 6,742
Vermont
Did you get those direct from AMAL ?


Originally Posted By: Paul744

Yes, I've just bought some.


Jon W.


1957 6T Thunderbird 650
1968 T100R Daytona 500
1971 TR6R Tiger 650
1970 BSA A65F 650
1955 Tiger 100 - Project

Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: JubeePrince] #425250
03/20/12 12:24 pm
03/20/12 12:24 pm
Joined: Aug 2001
Posts: 7,026
scotland
triton thrasher Online content
BritBike Forum member
triton thrasher  Online Content
BritBike Forum member
Joined: Aug 2001
Posts: 7,026
scotland
My bike runs better with the new alloy needles, but it had a definite problem with vibration causing flooding.

There may be less, or no benefit to your bike.


Amateur Loctite enthusiast.
Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: JubeePrince] #425252
03/20/12 12:26 pm
03/20/12 12:26 pm
Joined: Jul 2009
Posts: 3,549
Vic. Australia
P
Pete R - R.I.P. Offline
In Remembrance
Pete R - R.I.P.  Offline
In Remembrance
P
Joined: Jul 2009
Posts: 3,549
Vic. Australia
The original nylon needle weighed 0.3 gram.
This should give you a fuel level 0.205" +/- 0.035" below the top of the bowl,when the float toe is set 0.080" below the top of the bowl.
The viton tipped aluminium needle weighs 0.5 gram.This will give you the same fuel level,as long as you have a fuel head 5.5" above the bottom of the float bowl.That means it will work OK if there is some fuel in the tank.It takes 5.5" of fuel head to overcome the weight of the needle.If there isn't enough fuel head to overcome the needle weight,the fuel level in the bowl will be about 0.200" lower than it should be.The float is being used to open the needle,instead of closing it.

The viton-tipped brass needle weighs 1.7 gram.It takes about 13" or 14" of fuel head (above the bottom of the bowl) to overcome the weight of this needle.With less fuel than that,the only chance you have of getting the correct fuel level in the bowl is if vibration is lifting the needle off its seat.
If the fuel level ever became high enough,the float would then hold the needle closed.

I don't think the brass needle is a good idea.
Either float should work OK,once the level is set.

Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: Pete R - R.I.P.] #425263
03/20/12 2:05 pm
03/20/12 2:05 pm
Joined: Nov 2005
Posts: 7,259
Back on the mainland!
JubeePrince Online content OP

Life member
JubeePrince  Online Content OP

Life member
Joined: Nov 2005
Posts: 7,259
Back on the mainland!
Originally Posted By: Pete R

The viton tipped aluminium needle weighs 0.5 gram.This will give you the same fuel level,as long as you have a fuel head 5.5" above the bottom of the float bowl.That means it will work OK if there is some fuel in the tank.It takes 5.5" of fuel head to overcome the weight of the needle.If there isn't enough fuel head to overcome the needle weight,the fuel level in the bowl will be about 0.200" lower than it should be.The float is being used to open the needle,instead of closing it.

The viton-tipped brass needle weighs 1.7 gram.It takes about 13" or 14" of fuel head (above the bottom of the bowl) to overcome the weight of this needle.With less fuel than that,the only chance you have of getting the correct fuel level in the bowl is if vibration is lifting the needle off its seat.
If the fuel level ever became high enough,the float would then hold the needle closed.


So if I understand you correctly Pete, you're saying that with the brass needle and partially filled tank that the mixture would be too lean? (Assuming all things being equal, properly jetted, float height correct, etc).

When you say fuel head, what does that mean exactly? The height of the fuel in the tank and fuel line?

Steve

Last edited by JubeePrince; 03/20/12 2:06 pm. Reason: mixture would be...

'77 T140J
"Vintage Bike". What's in your garage?

"The paying customer is always right."

Fitting round pegs into square holes since 1961...
Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: Pete R - R.I.P.] #425265
03/20/12 2:12 pm
03/20/12 2:12 pm
Joined: Nov 2011
Posts: 4,077
U.S.
Magnetoman Online content

BritBike Forum member
Magnetoman  Online Content

BritBike Forum member
Joined: Nov 2011
Posts: 4,077
U.S.
Originally Posted By: Pete R
The original nylon needle weighed 0.3 gram.
This should give you a fuel level 0.205" +/- 0.035" below the top of the bowl,when the float toe is set 0.080" below the top of the bowl.
The viton tipped aluminium needle weighs 0.5 gram.This will give you the same fuel level,as long as you have a fuel head 5.5" above the bottom of the float bowl.That means it will work OK if there is some fuel in the tank.It takes 5.5" of fuel head to overcome the weight of the needle.
I'm in an airport waiting for a weather-delayed flight, so I haven't taken the time to reverse engineer your calculation, but it appears you've calculated the pressure of a column of gasoline (pounds/sq. inch, or grams/sq. cm) and equated that to the mass difference. If so, that's an incorrect calculation. And, it's not how the float needle works anyway.

The needle is pushed against the seat by the float acting through a ~4:1 lever arm, and flow ceases when the pressure on the seat equals or exceeds the pressure head of the fuel in the tank above. It's true that the float has to lift a bit more weight if the needle is brass instead of plastic or Al, but that's a minor effect. The level of the gasoline just has to rise enough around the large float to displace the additional 1 gram (or whatever) of weight, at which point the pressure on the seat will be the same as if the needle weighed less.

Since there's no AMAL handy in the airport to measure, I'll guess that the cross section of a float is ~2.5 cm, so the area immersed in fuel is ~6 cm^2. If the fuel level rises an additional 0.1 cm (i.e. only 0.039", which is within the specs needed to set the level) above where it was with a plastic needle, it will displace 0.6 cm^3 of fuel. The density of gasoline is less than that of water (1 gm/cm^3), so rather than googling it let's guess it's 0.6 gm/cm^3 to make the calculation simple. That's 0.6 grams of additional fuel that has been displaced. With the 4:1 leverage, this means the rise of only ~0.04" of the fuel in the bowl will lift a needle weighing 2.4 grams more than the plastic needle. So, the weight of the needle does affect the height of the fuel in the bowl, but by very little.

Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: Magnetoman] #425266
03/20/12 2:22 pm
03/20/12 2:22 pm
Joined: Nov 2008
Posts: 2,712
Bishop, Calif.
D
desco Online content
BritBike Forum member
desco  Online Content
BritBike Forum member
D
Joined: Nov 2008
Posts: 2,712
Bishop, Calif.
Why I love this web site.


1968 T120R
1972 T120RV
Any advice given is without a warranty expressed or implied.
Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: Magnetoman] #425269
03/20/12 2:29 pm
03/20/12 2:29 pm
Joined: Jul 2009
Posts: 3,549
Vic. Australia
P
Pete R - R.I.P. Offline
In Remembrance
Pete R - R.I.P.  Offline
In Remembrance
P
Joined: Jul 2009
Posts: 3,549
Vic. Australia
If you see how much clearance there is in the needle groove,the float has to drop a long way before it can lift the weight of the needle (about 0.200" at the toe).
It shouldn't have to lift the weight of the needle.The fuel pressure should lift the needle,and the float should be on the closing side of the groove.

The figures are from tests using fuel in a fuel line (static,not on a running engine).There is a sudden change of fuel level in the bowl at 5.5" with an aluminium needle,and about 13" for the brass needle.The height of the float changes approx 0.200".

Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: Pete R - R.I.P.] #425290
03/20/12 4:25 pm
03/20/12 4:25 pm
Joined: Nov 2011
Posts: 4,077
U.S.
Magnetoman Online content

BritBike Forum member
Magnetoman  Online Content

BritBike Forum member
Joined: Nov 2011
Posts: 4,077
U.S.
Originally Posted By: Pete R
If you see how much clearance there is in the needle groove,the float has to drop a long way before it can lift the weight of the needle (about 0.200" at the toe).
It shouldn't have to lift the weight of the needle.The fuel pressure should lift the needle,and the float should be on the closing side of the groove.

The figures are from tests using fuel in a fuel line (static,not on a running engine).There is a sudden change of fuel level in the bowl at 5.5" with an aluminium needle,and about 13" for the brass needle.The height of the float changes approx 0.200".
a quick reply before they close the doors on the plane. I think you're confused about the operation. Also, static tests are a problem due to uncontrollable amount of static friction/sticking. This is indicated by the "sudden" change you see.

Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: JubeePrince] #425311
03/20/12 6:35 pm
03/20/12 6:35 pm
Joined: Aug 2001
Posts: 7,026
scotland
triton thrasher Online content
BritBike Forum member
triton thrasher  Online Content
BritBike Forum member
Joined: Aug 2001
Posts: 7,026
scotland
The free play between the float's fork and the needle surfaces above and below it is noticeably huge on a Concentric.

A Monobloc float, which lifts the needle to close the valve, looks like it would work properly the way Magnetoman describes.

I experimented with narrowing the gap on a Concentric, but didn't really get anywhere.


Amateur Loctite enthusiast.
Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: triton thrasher] #425321
03/20/12 7:36 pm
03/20/12 7:36 pm
Joined: Nov 2011
Posts: 4,077
U.S.
Magnetoman Online content

BritBike Forum member
Magnetoman  Online Content

BritBike Forum member
Joined: Nov 2011
Posts: 4,077
U.S.
Originally Posted By: triton thrasher
The free play between the float's fork and the needle surfaces above and below it is noticeably huge on a Concentric.

A Monobloc float, which lifts the needle to close the valve, looks like it would work properly the way Magnetoman describes.

I experimented with narrowing the gap on a Concentric, but didn't really get anywhere.
In transit at DFW so again brief. Gravity acting on needle helps open it on Monobloc and close it on Concentric but, as my earlier post showed, effect on fuel level is tiny in both cases. Only one side of groove matters. Float always pushes on it. The amount of play in groove doesn't matter.

Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: Jon W. Whitley] #425327
03/20/12 8:02 pm
03/20/12 8:02 pm
Joined: Aug 2007
Posts: 160
England
P
Paul744 Offline
BritBike Forum member
Paul744  Offline
BritBike Forum member
P
Joined: Aug 2007
Posts: 160
England
Originally Posted By: Jon W. Whitley
Did you get those direct from AMAL ?


My parts man gets them direct from AMAL.
HTH

Last edited by Paul744; 03/20/12 8:02 pm.
Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: Magnetoman] #425334
03/20/12 8:35 pm
03/20/12 8:35 pm
Joined: Nov 2011
Posts: 4,077
U.S.
Magnetoman Online content

BritBike Forum member
Magnetoman  Online Content

BritBike Forum member
Joined: Nov 2011
Posts: 4,077
U.S.
Again, before the door of this next plane closes, I spotted a mistake I made in earlier post. Should have been 0.6g/cm^3 x 0.6cm^3= 0.36 grams. That times 4x leverage = ~1.4 grams. Slightly diff. number but same conclusion. The material the float is made from has negligible effect on fuel level.

Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: Magnetoman] #425337
03/20/12 8:46 pm
03/20/12 8:46 pm
Joined: Aug 2001
Posts: 7,026
scotland
triton thrasher Online content
BritBike Forum member
triton thrasher  Online Content
BritBike Forum member
Joined: Aug 2001
Posts: 7,026
scotland
Originally Posted By: Magnetoman
Originally Posted By: Pete R
The original nylon needle weighed 0.3 gram.
This should give you a fuel level 0.205" +/- 0.035" below the top of the bowl,when the float toe is set 0.080" below the top of the bowl.
The viton tipped aluminium needle weighs 0.5 gram.This will give you the same fuel level,as long as you have a fuel head 5.5" above the bottom of the float bowl.That means it will work OK if there is some fuel in the tank.It takes 5.5" of fuel head to overcome the weight of the needle.
I'm in an airport waiting for a weather-delayed flight, so I haven't taken the time to reverse engineer your calculation, but it appears you've calculated the pressure of a column of gasoline (pounds/sq. inch, or grams/sq. cm) and equated that to the mass difference. If so, that's an incorrect calculation. And, it's not how the float needle works anyway.

The needle is pushed against the seat by the float acting through a ~4:1 lever arm, and flow ceases when the pressure on the seat equals or exceeds the pressure head of the fuel in the tank above. It's true that the float has to lift a bit more weight if the needle is brass instead of plastic or Al, but that's a minor effect. The level of the gasoline just has to rise enough around the large float to displace the additional 1 gram (or whatever) of weight, at which point the pressure on the seat will be the same as if the needle weighed less.

Since there's no Amal handy in the airport to measure, I'll guess that the cross section of a float is ~2.5 cm, so the area immersed in fuel is ~6 cm^2. If the fuel level rises an additional 0.1 cm (i.e. only 0.039", which is within the specs needed to set the level) above where it was with a plastic needle, it will displace 0.6 cm^3 of fuel. The density of gasoline is less than that of water (1 gm/cm^3), so rather than googling it let's guess it's 0.6 gm/cm^3 to make the calculation simple. That's 0.6 grams of additional fuel that has been displaced. With the 4:1 leverage, this means the rise of only ~0.04" of the fuel in the bowl will lift a needle weighing 2.4 grams more than the plastic needle. So, the weight of the needle does affect the height of the fuel in the bowl, but by very little.


When you have time, please start again and make it brief. I'm baffled: a rise in the fuel level in the bowl of a Concentric doesn't lift the needle. It lifts the float, which pushes the needle down.


Amateur Loctite enthusiast.
Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: JubeePrince] #425361
03/20/12 11:08 pm
03/20/12 11:08 pm
Joined: Sep 2007
Posts: 1,575
El Dorado, California
Roadwarrior Offline

Private Sponsor
Roadwarrior  Offline

Private Sponsor
Joined: Sep 2007
Posts: 1,575
El Dorado, California
I think Paul744 answered your question Steve. As for me, I like the old nylon needles as they seem to cause me less problems.


Bob


73 Triumph T140 Main Ride
70 Bonnie
67 BSA West Coast Hornet

56 Chevy

Who are the brain police?



Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: JubeePrince] #425367
03/20/12 11:29 pm
03/20/12 11:29 pm
Joined: Mar 2005
Posts: 10,024
Boston, Massachusetts
J
John Healy Online content

BritBike Forum member
John Healy  Online Content

BritBike Forum member
J
Joined: Mar 2005
Posts: 10,024
Boston, Massachusetts
Quote:
As for me, I like the old nylon needles as they seem to cause me less problems.


Bob, you must excuse me (and please take no offense) as I find this amusing as I am old enough, and been distributing these this for way too long, and remember everyone complaining about the nylon needles. That is why we got the brass ones in the first place.

I guess we didn't know how well we had it. Could the mass collective of British enthusiasts have had brass needle envy as Mikuni's came with them and we didn't want to be left behind...

This discussion is as old as AMAL brass needles themselves...


Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: Magnetoman] #425368
03/20/12 11:30 pm
03/20/12 11:30 pm
Joined: Jul 2009
Posts: 3,549
Vic. Australia
P
Pete R - R.I.P. Offline
In Remembrance
Pete R - R.I.P.  Offline
In Remembrance
P
Joined: Jul 2009
Posts: 3,549
Vic. Australia
Originally Posted By: Magnetoman

Only one side of groove matters. Float always pushes on it. The amount of play in groove doesn't matter.

This is not the case,when needle weight alone is enough to overcome fuel pressure and prevent fuel flowing into the bowl.With a brass needle,this will happen when the tank fuel level is below about 3/4 full.

The needle then needs to be lifted by the float (or some other means) to allow fuel into the bowl.For the float to lift the needle,it must drop a long way and operate on the other side of the needle groove.The float will drop this amount only if the fuel level in the bowl drops too.

Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: Paul744] #425400
03/21/12 2:46 am
03/21/12 2:46 am
Joined: Aug 2001
Posts: 6,742
Vermont
Jon W. Whitley Online content

BritBike Forum member
Jon W. Whitley  Online Content

BritBike Forum member
Joined: Aug 2001
Posts: 6,742
Vermont
Thanks Paul. Just wanted to narrow the origin down
a bit.

Originally Posted By: Paul744


My parts man gets them direct from AMAL.
HTH


Jon W.


1957 6T Thunderbird 650
1968 T100R Daytona 500
1971 TR6R Tiger 650
1970 BSA A65F 650
1955 Tiger 100 - Project

Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: triton thrasher] #425407
03/21/12 3:37 am
03/21/12 3:37 am
Joined: Nov 2011
Posts: 4,077
U.S.
Magnetoman Online content

BritBike Forum member
Magnetoman  Online Content

BritBike Forum member
Joined: Nov 2011
Posts: 4,077
U.S.
Originally Posted By: triton thrasher
When you have time, please start again and make it brief. I'm baffled: a rise in the fuel level in the bowl of a Concentric doesn't lift the needle. It lifts the float, which pushes the needle down.

After a long day of delayed flights, followed by a great meal with lots of single malt whiskey and wine, I'm finally in my hotel room. Still, I'd like to go to sleep, so I'll keep this brief.

Indeed, just as you say (and as I said, albeit in a more lengthy way), a rise in fuel level in a Concentric pushes the needle down against the seat and stops the flow. In this endeavor it is helped in a teensy way by gravity acting on the weight of the needle, which pulls a brass needle down a bit harder than it does a nylon needle. As a result, if a nylon needle were replaced by a brass needle of *precisely* the same dimensions, and if nothing else were changed, the float level would be lowered by ~0.04" or so after the substitution. This is a negligible amount. Since the float in a Monobloc pushes the needle up, the same principle is true for it, except it works in the opposite direction. That is, the float level would be raised by ~0.04" or so after the same substitution.

Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: Pete R - R.I.P.] #425409
03/21/12 4:07 am
03/21/12 4:07 am
Joined: Nov 2011
Posts: 4,077
U.S.
Magnetoman Online content

BritBike Forum member
Magnetoman  Online Content

BritBike Forum member
Joined: Nov 2011
Posts: 4,077
U.S.
Originally Posted By: Pete R
Originally Posted By: Magnetoman

Only one side of groove matters. Float always pushes on it. The amount of play in groove doesn't matter.
This is not the case,when needle weight alone is enough to overcome fuel pressure and prevent fuel flowing into the bowl.With a brass needle,this will happen when the tank fuel level is below about 3/4 full.

The needle then needs to be lifted by the float (or some other means) to allow fuel into the bowl.For the float to lift the needle,it must drop a long way and operate on the other side of the needle groove.The float will drop this amount only if the fuel level in the bowl drops too.
You would be correct for a Concentric (not a Monobloc) if the needle weight was high enough that the pounds/in^2 (or grams/cm^2) it exerted on the surface area of the seat due to gravity were large enough to overcome the pounds/in^2 of the pressure head of the fuel above it. I'm going to bed now, but urge you to do this calculation and post the result.

Last edited by Magnetoman; 03/21/12 7:55 pm. Reason: deleted duplicate quotation
Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: John Healy] #425469
03/21/12 3:22 pm
03/21/12 3:22 pm
Joined: Nov 2005
Posts: 7,259
Back on the mainland!
JubeePrince Online content OP

Life member
JubeePrince  Online Content OP

Life member
Joined: Nov 2005
Posts: 7,259
Back on the mainland!
Originally Posted By: John Healy

This discussion is as old as Amal brass needles themselves...


John -

I assume you're talking about brass vs. nylon and not brass vs. aluminum. If the latter, I'd love to hear your thoughts on it.

Perhaps I'll shell out a few bucks and try the aluminum ones myself and post the results (or lack of) here.

Steve


'77 T140J
"Vintage Bike". What's in your garage?

"The paying customer is always right."

Fitting round pegs into square holes since 1961...
Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: JubeePrince] #425499
03/21/12 5:46 pm
03/21/12 5:46 pm
Joined: Mar 2005
Posts: 10,024
Boston, Massachusetts
J
John Healy Online content

BritBike Forum member
John Healy  Online Content

BritBike Forum member
J
Joined: Mar 2005
Posts: 10,024
Boston, Massachusetts
Steve:

This discussion brass vs nylon has been going on since the brass needle jet was first introduced.

There continues to be a small vocal group who bemoan the discontinuation of the nylon needle and introduction of the brass needle jet. This some 30 years after the introduction. I personally never had reason to explore the difference, feeling that I was able to get the carburetor kitted with the brass needle to do everything I asked from the carburetor.

I will send down a couple aluminum ones and you can try them...

edit: they are in the mail.

Last edited by John Healy; 03/21/12 6:52 pm.

Re: Amal float needle: Brass/viton vs. aluminum/viton [Re: John Healy] #425526
03/21/12 7:51 pm
03/21/12 7:51 pm
Joined: Nov 2011
Posts: 4,077
U.S.
Magnetoman Online content

BritBike Forum member
Magnetoman  Online Content

BritBike Forum member
Joined: Nov 2011
Posts: 4,077
U.S.
Originally Posted By: John Healy
There continues to be a small vocal group who bemoan the discontinuation of the nylon needle and introduction of the brass needle jet. This some 30 years after the introduction.
When provided with evidence that brass needles actually do work (and, indeed, have worked in countless motorcycles for 30 years), there are two choices: 1) continue to argue they can't work, or 2) use it as a learning opportunity, by examining one's underlieing assumptions to determine the reason for the incorrect belief.

Page 1 of 2 1 2

Moderated by  John Healy 


Home | Sponsors | Newsletter | Regalia | Calendar | Bike Project | BritBike Museum | Spiders Cartoons | "OLD" BritBike Forum | DVD- Manuals & Parts books | BritBike Stickers & Decals
Upgrade to: Premium Membership | Premium Life Membership | Vendor Membership | Site Sponsor Membership
Powered by UBB.threads™ PHP Forum Software 7.6.1.1