ET: Engine (Twin) 32 MM Amal TT jetting
- Thread starter Cyborg
- Start date
The settings in "Richardson" worked for me with a 1 5/32" T10TT on a single years ago when men were men and petrol was petrol. 360 main, 7 slide, 4 needle position and 0.109 needle jet.
Thank you.
I have 360 mains and the the needle jets are 109 which is good because 109’s are readily available. The needle has a 10 or maybe 01 stamped on it, which seems to be the same as the other TT’s. Burlin only lists one needle with presumably their stock number (RKTT/2), so I assume that needle will work. The list I have (from Amal) doesn’t even mention needles?
Thankfully I already have a couple of NOS #7 slides.
We can still buy real fuel here, although you have to be fairly wealthy to fill the tank.
It may get to the point where we have to distill the bathtub gin and use that. Add a few drops of R40 instead of quinine.
I have 360 mains and the the needle jets are 109 which is good because 109’s are readily available. The needle has a 10 or maybe 01 stamped on it, which seems to be the same as the other TT’s. Burlin only lists one needle with presumably their stock number (RKTT/2), so I assume that needle will work. The list I have (from Amal) doesn’t even mention needles?
Thankfully I already have a couple of NOS #7 slides.
We can still buy real fuel here, although you have to be fairly wealthy to fill the tank.
It may get to the point where we have to distill the bathtub gin and use that. Add a few drops of R40 instead of quinine.
The jet size for alcohol listed as a 1700 is basically the largest jet Amal made........To actually run a 1000 cc twin on alcohol using a 1700 would be insanely rich.......Even with my mildly tuned racer in my picture.......The mains were 820 and even these were on the rich side........So even a 360 for petrol fuels will probably still be way rich........Mind you, how long will you have it on full throttle anyway.
Somehow I had it in my head that 1400 was a reasonable number , but no idea how it got there. Maybe confusing that with the Gold Star… who knows. I was surprised when I saw 1700. It won’t see much WOT, but at least it is being built to withstand a beating.…. I’m assuming it won’t be quite as terrifying as the Ducati.
The thing to remember is the exhaust,
I think I used up to 400 main with Twin 2" open pipes ?,
But you will have some kind of silencer ?,
Comets might need a bit more petrol than Twins ?
In UK they had come down from the super 100 octane at the road side pumps,
So by 1980 when I built my L/ning rep', I was only running 9 to 1 pistons,
No 2 engines are the same, So 370 380 etc are a good starting point.
Good Luck, Bill.
I think I used up to 400 main with Twin 2" open pipes ?,
But you will have some kind of silencer ?,
Comets might need a bit more petrol than Twins ?
In UK they had come down from the super 100 octane at the road side pumps,
So by 1980 when I built my L/ning rep', I was only running 9 to 1 pistons,
No 2 engines are the same, So 370 380 etc are a good starting point.
Good Luck, Bill.
Well I’m at 150’ so will start with what I have. As far as I know the carburetors were last used in LA which would be similar elevation, although the air is a little denser here in the summer…. at least so far.
I have two sets of pipes, 1 5/8 and 2”. I plan on trying the 2” pipes and just see how loud they are. There seems to be a variety of baffles available that can just slip inside if they are two nasty. It’s amazing what people get away with here, but I don’t want to be one of them unless it’s just to get even with my next door neighbour.
I fellow who raced a Vincent outfit told me he ran both 1 5/8 and 2“ pipes and the smaller pipes were louder and sounded a bit nastier. My brother used the small pipes, but quickly decided he couldn’t afford the tickets.
132 sounds pretty good. I’m running 8:1 because by the time I’m finished this thing I’ll need an electric leg or a Coffman starter.
I have two sets of pipes, 1 5/8 and 2”. I plan on trying the 2” pipes and just see how loud they are. There seems to be a variety of baffles available that can just slip inside if they are two nasty. It’s amazing what people get away with here, but I don’t want to be one of them unless it’s just to get even with my next door neighbour.
I fellow who raced a Vincent outfit told me he ran both 1 5/8 and 2“ pipes and the smaller pipes were louder and sounded a bit nastier. My brother used the small pipes, but quickly decided he couldn’t afford the tickets.
132 sounds pretty good. I’m running 8:1 because by the time I’m finished this thing I’ll need an electric leg or a Coffman starter.
I´d love the Coffman starter !! But then , I´d get all sorts of biiig troubles here with authorities about the cartridges .
Is it really a good idea with the 2" pipes on basically 500 cc cylinders ? The exhaust gases will be slower than with smaller pipes and I don´t think you´d find 2 " pipes on other 500 cc racers ?? For some silencing you´ll need a decent silencer, a gizmo shoved up the pipe will ruin the performance.
Vic
Is it really a good idea with the 2" pipes on basically 500 cc cylinders ? The exhaust gases will be slower than with smaller pipes and I don´t think you´d find 2 " pipes on other 500 cc racers ?? For some silencing you´ll need a decent silencer, a gizmo shoved up the pipe will ruin the performance.
Vic
Sorry Ken, I forgot you are doing a Twin, Thought you was talking about your Comet Special,
I agree the smaller Ex pipes are louder, Sharper !,
I loved my 2" pipes, But the ground clearance was not enough,
I am not good on the corners, I laid the bike over in the garden and thought
There was no way they would touch, But first bend , First race, Donington Park And they touched !.
And also the kick start is tricky with 2" pipes, Although I did a job on the Kicker !!.
One of the lads runs air filters , Don't know if that would make it richer ?.
Cheers Bill.
I agree the smaller Ex pipes are louder, Sharper !,
I loved my 2" pipes, But the ground clearance was not enough,
I am not good on the corners, I laid the bike over in the garden and thought
There was no way they would touch, But first bend , First race, Donington Park And they touched !.
And also the kick start is tricky with 2" pipes, Although I did a job on the Kicker !!.
One of the lads runs air filters , Don't know if that would make it richer ?.
Cheers Bill.
