MotorBicycleRacing
Well-Known Member
Take the worthless boost bottle off and see how it runs.
Well I thought it was a carb issue...
- Thread starter Stoneman
- Start date
gary55
Well-Known Member
From what I've seen on jet corrections You would need to be living at around 15000 ft abv. sea level for a .55mm jet to work. I'm at 5400 and these carbs don't like it here. they tend to run a little richer than the NT. A #68 works good on my NT's where the dell. clones want a #66 or #64.
I have read where folks at lower elev. have better luck with them, but I find the NT much more forgiving when trying to fine tune the jetting.
One thing you could look at on your head milling is if it is warped enough were the outer corners of the head by the holes are not higher than the matting surface of the ring they will bottom out before allowing the gasket to seal.
I have read where folks at lower elev. have better luck with them, but I find the NT much more forgiving when trying to fine tune the jetting.
One thing you could look at on your head milling is if it is warped enough were the outer corners of the head by the holes are not higher than the matting surface of the ring they will bottom out before allowing the gasket to seal.
Awesome,
Great info to get started. Hopefully get it back together tonight, just need to clean up the manifolds that shouldn't take long
Remove the boost bottle!! But it's so cool!
@Steve thanks for that info, I won't get into the compression stage quite yet as I have a couple extra of heads with the spark plug in the centre. Found a bloke that will machine it what ever I want for $20 bucks. Got to do some learnen first
Gary I'm not sure what my sig states but if it helps I'm in Melbourne if it makes a difference
But a 55 is around where it's at ,
Great info to get started. Hopefully get it back together tonight, just need to clean up the manifolds that shouldn't take long
Remove the boost bottle!! But it's so cool!
@Steve thanks for that info, I won't get into the compression stage quite yet as I have a couple extra of heads with the spark plug in the centre. Found a bloke that will machine it what ever I want for $20 bucks. Got to do some learnen first
Gary I'm not sure what my sig states but if it helps I'm in Melbourne if it makes a difference
But a 55 is around where it's at ,
Steve Best
Well-Known Member
Actually boost bottles do work. I got pictures:
This is my boost bottle experiment. The connector hose is the same 14mm as the intake tract and it has a 1.25" (32mm) "bottle" section of clear vinyl tube, which has an adjustable plunger in it so I can change the volume and tuning. Detail of the intake connection:
I tried JB weld but it did not hold so the the copper pipe is soldered to the steel intake and holds well.
What we have here is a Helmholtz Resonator.
Tune it to the right frequency and it will work wonders for you, but only at that frequency.
I was able to tune it for stump pulling power for clutch starts, or good mid-range, or a little more power on peak, but not all at the same time. No one setting had an advantage that made the extra complication and potential leaks worth the trouble. Interesting experiment, they do work.
As for the 200ml bottles with the 6mm line? I wasn't able to see an effect.
This is my boost bottle experiment. The connector hose is the same 14mm as the intake tract and it has a 1.25" (32mm) "bottle" section of clear vinyl tube, which has an adjustable plunger in it so I can change the volume and tuning. Detail of the intake connection:
I tried JB weld but it did not hold so the the copper pipe is soldered to the steel intake and holds well.
What we have here is a Helmholtz Resonator.
Tune it to the right frequency and it will work wonders for you, but only at that frequency.
I was able to tune it for stump pulling power for clutch starts, or good mid-range, or a little more power on peak, but not all at the same time. No one setting had an advantage that made the extra complication and potential leaks worth the trouble. Interesting experiment, they do work.
As for the 200ml bottles with the 6mm line? I wasn't able to see an effect.
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Frankenstein
Deceased - Frankenstein 1991 - 2018
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Yeah and they have another couple thousand available on ebay alongside the same listing as the gold head gasket (stock gasket sprayed with permatex copper gasket spray.)
Just because you can buy it doesn't make it a fantastic idea. Just because other people are dumb enough to buy it doesn't make it a great idea. Follow Steve's example and make a real one if you want it.
I'm not sure what your trying to say frank?
But so far it doesn't sound very welcoming......maybe just the way I'm reading it.
Do you understand why they don't work or are you just wanting to say I wasted my money because you don't understand them either?
Because if your saying I wasted my money you haven't seen my hobby room
My wife would love your support
Any way on with my problem
Oh and I just ordered half a dozen copper painted head gaskets it's not a race motor mate
But so far it doesn't sound very welcoming......maybe just the way I'm reading it.
Do you understand why they don't work or are you just wanting to say I wasted my money because you don't understand them either?
Because if your saying I wasted my money you haven't seen my hobby room
My wife would love your support
Any way on with my problem
Oh and I just ordered half a dozen copper painted head gaskets
it's not a race motor mate
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Well it seems I haven't gained anything
It runs, we can get revs (and smooth with jaguar's stock timing mod),it idles nice, revs crisp with no load but no power
So far after the suspected over heat I've surfaced the head and jug as above, gone back to stock NT carb with a 55 jet also sealed the carb with an o ring and played with needle settings
But no power or less than before the over heat
I'm currently thinking that we have either killed the head, need a new head gasket (I have the new heads I ordered with centre spark plug position).
Or we have killed the lot including jug and piston
Yet to do a compression test as I ran out time to get a new one and can't find my one ATM
Any ideas? Frank do you have any?
It runs, we can get revs (and smooth with jaguar's stock timing mod),it idles nice, revs crisp with no load but no power
So far after the suspected over heat I've surfaced the head and jug as above, gone back to stock NT carb with a 55 jet also sealed the carb with an o ring and played with needle settings
But no power or less than before the over heat
I'm currently thinking that we have either killed the head, need a new head gasket (I have the new heads I ordered with centre spark plug position).
Or we have killed the lot including jug and piston
Yet to do a compression test as I ran out time to get a new one and can't find my one ATM
Any ideas? Frank do you have any?
HumanPerson
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You do know that Jake doesn't like to be called Frank, don't you Stoneman?
Ride Safe
Ride Safe
gary55
Well-Known Member
Here is my Finding on heads as far as volume goes.View media item 60274Left to right 1. stock center hole head=10cc 2. stock slant plug head =6cc 3. after market pancake head=8cc 4. after market round fin head=8cc 5. after market flat fin head=8cc. View media item 60552 In the pic. with 3 heads the 2 on the right are #4 and 5 above, but the one on the left with the converging fins is a 6cc head. The 8cc heads will allow you to adjust your squish without putting your compression through the roof by decking the jug. If you are not planing on altering the deck they will lower your compression so the 6cc head would be the better choice.
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