gearing on my Seeley

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If you're still worrying about the family jewels at 70 maybe there is hope for the rest of us then :)
 
About the gearing: you must know that a TTI 5 speed road gearbox as a longer first gear as the original Norton, that explain maybe the use of the clutch at the traffic lights.

About my family jewels: I remember when I was 12 years old my dad says "it's time to speak about sex" OK Dad, what do you need to know?
Yves
 
Hi There,
Last saturday I did a long ride with two friends (Luc and Johan) it was very hot and we take different kind of roads and some traffic lights.
As you remember I change the final gearing from 19 X 39 to 21 X 39, I did a short test ride and was satisfed.
Saturday I feel that the gearing was to long on the traffic lights, must use the clutch more as usual, so I decide to go to 19 X 41, I dont test it so far becouse of raining, but this will be not far from perfection I hope.
I also change the main Jets on the FCR: from 175 to 180, this must give more cooling to the engine.
The oil pressure was good but as you maybe know on the Seeley there is a gap in the seat to fill the oil, wel saturday we spend some time in the traffic, stop and go, you know with as result that my family jewellery that are on the top of the gap in the seat, almost burn.
I find the solution: fill the gap with a piece of wood with the same hupholstry as on the seat, I can stiil take this piece away to fill the oil.
Keep you posted
Yves
With most carbs, main jets are only used at full throttle. When you accelerate changing up through the gears, it is usually the needles and needle jets which do the metering. I usually run slightly too rich on the mains, so that when I use full throttle the combustion temperatures are a bit lower. But even on a race track, you are not usually on full throttle for very long lengths of time.
I never worry about calculating gear ratios. It is what happens in practice - it is more important.
 
know on the Seeley there is a gap in the seat to fill the oil, wel saturday we spend some time in the traffic, stop and go, you know with as result that my family jewellery that are on the top of the gap in the seat, almost burn.
I find the solution: fill the gap with a piece of wood with the same hupholstry as on the seat, I can stiil take this piece away to fill the oil.
Keep you posted Yves
I'm almost tempted to say, " Great balls of fire!" :)
 
2 score year and 10 is a major milestone, just 5 years behind you. For what it is worth I believe 1 tooth on the front is worth 3 on the back. So the 21 x 39 would be the same as 19 x 45

From what I remember a score is 20, so 'Three score years and ten' is the biblical 'normal' human lifespan.....definitely a major milestone.

I am just over 3 years behind Yves, and like Yves, trying my best to avoid normal!

Good luck with it all Yves.
 
......as you maybe know on the Seeley there is a gap in the seat to fill the oil, wel saturday we spend some time in the traffic, stop and go, you know with as result that my family jewellery that are on the top of the gap in the seat, almost burn.
I find the solution: fill the gap with a piece of wood with the same hupholstry as on the seat, I can stiil take this piece away to fill the oil.
Keep you posted
Yves

Yves, as you maybe also know there is a similar gap on a Rickman, but if running in traffic makes it hot around there, try a 20 minute race on a Rickman with oil in the frame tubes, It was OK in the first season after the build, but the seat foam in the two forward sections seems to have settled and lowered me into the inferno! I use a piece of very dense foam rubber in there, but normally get burning on the inside of my thighs by the frame tubes themselves as I move about, it can mean riding the straights sat as far back as possible and sticking my knees into the airflow! Not very aerodynamic!
 
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Never mind the hot oil tank - I tried straight extended manifolds on my monoshock with tilted engine and the exposed velocity stacks were right there where you didn't want them (the rear of the fuel tank was cutout). After a couple of races and constant ribbing from my racer friends I had to redesign the tank to shield the velo stacks.
 
From what I remember a score is 20, so 'Three score years and ten' is the biblical 'normal' human lifespan.....definitely a major milestone.

I am just over 3 years behind Yves, and like Yves, trying my best to avoid normal!

Good luck with it all Yves.
Well spotted, I meant 3 but fat fingers on a phone and not checking are my excuses.
 
With most carbs, main jets are only used at full throttle. When you accelerate changing up through the gears, it is usually the needles and needle jets which do the metering. I usually run slightly too rich on the mains, so that when I use full throttle the combustion temperatures are a bit lower. But even on a race track, you are not usually on full throttle for very long lengths of time.
I never worry about calculating gear ratios. It is what happens in practice - it is more important.
Hi Acotel,
You are the king of the theory, wondering how many races you win in your racing days?
Main jets have influances also on accelarating
Yves
 
Hi There
To day I did a test ride after the last change I did on the Seeley:
First the gearing: the last one was 21 x 39, a bit to long, now I test 21 X 41 and this same to be perfect for my riding style.
Main Jets on the FCR: I go from 175 to 180, works very well.
Protection for my jewels: The protection works, they are protected like in a box from Cartier.
It was a beautifull Indian Summer day to day, sunny, 20 celcius, no wind, full happyness to ride the Seeley over the Ton.
keep you posted
Yves
 
Nice to hear you’ve got the hearing sorted Yves.

Also interesting to hear your main jet experiences.

keep on keeping on !!
 
Yves, when I was racing regularly years ago, I won almost nothing. It was mainly due to the bike being under capacity for the class in which it raced, p[us being ten years older than most of the other bikes. . These days, with the Seeley 850, it is much easier and I have won a few.. I have always found there are two situations - accelerating out of corners and carrying speed at the ends of the straights. On the circuits in which I usually race when I get the opportunity, the straights are not very long and if I lose a bit at the ends of the straights, it is not much because I get around and out of the corners and into the straights faster. My main jets are slightly over size, but my needles and needle jets are critical. If the main jet is slightly too big, the bikes is slightly more sluggish, but it usually does not matter. I never whack the throttle open, I always feed it on in a controlled fashion. If you are jetted lean enough in the midrange to get best acceleration, you are forced to do that - even with standard size inlet ports..
 
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Nice to hear you’ve got the hearing sorted Yves.

Also interesting to hear your main jet experiences.

keep on keeping on !!
Hi Nigel,
I use Keihin FCE for years, at the begining I spend a lot of time on the dino, now, with years experience, I can feel if the jeting is ok, even if it the bike run good, I can feel if the bike run a bit to lean or to ritch.
How: first the sound of the exhaust, then the temperature of the head, color of the spark plug.
I have also the whole range of main jets, air jets, pilot jets, needels and so on, to play with it.
Yves
 
If you’re running 180s Yves then mine is highly likely to be lean on the main jet. I don’t have your ear or feel, so really need to get my act together and get it back on the dyno !
 
Does a dyno tell you when you are going to burn a piston ? Can you hear detonation over the other noise ?
 
If it has a gas analyser Al it will tell you the AF ratios. It’s a good starting point for carb settings. A good dyno operator will get a better result than a not so good one. Its not just a ‘press the button’ type of job.

Final setting should always be arrived at on the road, or track of course.

But I’m stating the obvious, we know all this. Not sure what your point is really...
 
If you’re running 180s Yves then mine is highly likely to be lean on the main jet. I don’t have your ear or feel, so really need to get my act together and get it back on the dyno !
Hi Nigel,
I forgot to say about jeting: first look at the colour inside the back of your exhaust.
You can not compare jeting between two engines, to many factors are involded like CR, camshaft, squish band, advance, exhaust, capacity and more.
Yves
 
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