[RidingHood]

Cams=Megacycle510-60 ,a bloke here in Aussieland says these are the ones for big bore
Tuning your carb : start with getting the main jet correct ,a full throttle run(as the other posts suggest) for a 1/4 mile, up a very slight incline if you can as that makes the engine 'work' .Immediately kill the engine AND pull in the clutch at the same time.This is so you can see what the mixture was like at full throttle (Tan to light grey around the centre electode is what you are looking for) .White or blistered =lean,Dk brown /black=rich.then do idle(idle jet, but most modern concentrics have a fixed idle jet size) .Then do throttle cut away which controls 1/8-1/4 throttle then needle height 1/4 -3/4 throttle.I could go on but Seriously if you can wait a little i'll scan the Amal Hints and Tips booklet and post it on this forum,it says it all and is invaluable.
Drag pipes with a straight cut end are a pain on a street Bike(I speak from experience as it will run fine at a certain rpm but not at other)a slash cut is better as it reduces the strength of the pulse that effects exhaust tuning.
I wouldnt be too worried about the intake length on a single carb triumph but MAP did sell a bigger single carb manifold 32-34mm
It is worth reading the followng books ,as once you understand the theory behind performance mods,you are better able to know how to spend (and save your bucks)
Triumph tuning by Stan Shenton its an oldie but a goodie.
Tuning for speed by Phil Irving another oldie and it keeps being reprinted
The Big Twin high-Performance Guide by D.William Denish.yeah even though its focus is HD the theory applies to four stokes in general .I'd rate this as one of the best perfomance books on the market -bike or car.
Ok its late here and i'll post that carb stuff as soon as I can ,oh yeah the year of your cylinder head is cast inside the head in the area between the inlet valve guides.
cheers

 

[Flyin' Dutchman]

Thanks!!

Can't wait to see the carb stuff..!

This thread is becoming very interesting..

It's really cool to see so many Triumph guys on here!

 

[Flyin' Dutchman]

Made another test spin a minute ago...

I got rid of my leakage trouble.. it's only leaking at the Webco oil cooler, but that's just a small problem to solve.

Scrambler pipes (1 3/8 diam) make no difference...

Like the motocross guys overhere say when a bike has no pulling power: "The bike can't even pull a German sausage off of a slanted roof!!"
At least, that's the feeling I have when riding...

I haven't done the WOT/killswitch trick yet...

Pipes aren't turning blue, so it's not too lean, but when the bike is idling and I give a little throttle burst, there's some fuel coming through the webbing of the velocity stack...

When I open the throttle, after about 1/3 or half throttle, I have the feeling I'm going nowhere...
Someone on here said earlier, that the Joe Hunt mag doesn't advance enough.. My dad told it to me all the time, last year also... First I didn't believe it, but I'm thinking more and more that you guys are right.

I can't find much else that's wrong with my bike... All I want is to get the noise down a little, and then at the same time other pipes will give a bit more back pressure. And I want a mag that advances more...

Seems that an ARD mag "does" advance over the whole RPM range... Maybe I should go for one of those...
How much are they? I couldn't find a price on Britcycle.com

 

[Brian Douglas]

When I open the throttle, after about 1/3 or half throttle, I have the feeling I'm going nowhere...
Someone on here said earlier, that the Joe Hunt mag doesn't advance enough..

the is NO advance on a hunt mag

if it runs good at idle, you will have NO power at high RPMs, as it will be running retarded

thats exactly why i went with a boyer
if i had known about the ARD CDI, i would have gone that route

 

[GumbyChuck]

Pipes aren't turning blue, so it's not too lean, but when the bike is idling and I give a little throttle burst, there's some fuel coming through the webbing of the velocity stack...

rich at part throttle - drop your needle a clip
might have reversion problem too - how long are your pipes?

Seems that an ARD mag "does" advance over the whole RPM range... Maybe I should go for one of those...
How much are they? I couldn't find a price on Britcycle.com

last I saw, around $500US

 

[Brian Douglas]

rich at part throttle - drop your needle a clip
might have reversion problem too - how long are your pipes?

last I saw, around $500US

retarded ignition acts like its rich

this is the only way i know of how to make a hunt work sorta right for street, a guy from cirrillo magneto helped me do this initialy (bare with me, it was a long time ago)

use the tdc body plunger to set pistons @ 38degrees btdc and setup mag per hunt's instructions(full advance)
mark position on adaptor plate and mag housing, this is your full advance mark
rotate mag back to 14degrees btdc and mark adator plate, this is your full retard mark

start bike at retard mark, manually advance mag as far as you can without killing it, and if you want to GO, kick mag to full advance mark

you could rig something up as a full advance stop

i had my idle pretty high, that helped a bit

has to be fully advanced to read plugs after WOT

 

[RidingHood]

G'day Flyin'Dutchman,
Got a mate to scan the Amal carb pamphlet,but because the writing is so small on the original, that it is not readable once on the computer.So tomorrow I will do an enlargement on the photocopy machine and then scan that,and hopefully that will solve the problem.
cheers

 

[Boyd Who]

First post on this board, but it's a tech post. Anyone from the HAMB will probably know who I am.

I used to build/ride 650 Triumphs in the mid 80's. Someday I'll build another one, when my finances allow.

I had a 1970 650 Bonneville chopper that I messed around with a bit. I'll pass on one of the best tips I ever found regarding getting it to run well with the factory Amals. Hopefully my memory on this is correct, maybe someone else has heard of this. It worked wonders for my bike.

I was told to trade the twin-carb Bonny head for a single-carb Tiger head. Take the carb apart and toss out the choke assembly and the idle speed set screw. Use something to fill the hole left by the set screw so there's no air leaks.

Pull the slide out of the carb. There is a curved side and a flat side with the flat side going towards the engine. Take a jewellers saw, or be very careful with a hacksaw blade, and cut away a 1/8" square piece of material from the flat (engine) side. This will allow the engine to idle at a constant speed, no matter what the conditions. Start at 1/8", and if it isn't quite enough for a decent idle speed, carefully increase the size of the hole. This hole is the reason you won't need the idle speed screw. The choke isn't needed anymore either.

I did this to my bike in 1984 and it worked like a damn! I was forever messing with the dual carbs trying to sync them, without much luck. Idle speeds would vary from minute to minute, very frustrating.

Another trick that helped the bike, and this will work on pretty much any Brit twin, is to toss the stock dual coils. Pick up a good Harley coil with dual plug wires. Tie the two wires for the points together and run them to the single coil. The bike will fire every two strokes instead of 4 (power & exhaust), but that doesn't hurt anything.

After these two tricks my bike became a one-kick bike, no matter what the conditions. I plan to utilize them again when I build my next bike.

Here's a pic of the bike in question (black one), plus the one I was building when my world fell apart in 1985 (blue one). The black one was taken before the head swap. The b&w pic is what the black one looked like when I started the project.