1007 Seeley Commando dyno run

A dyno is good for improving engine power. But improvements which allow power to be used more effectively might be more important. Nobody in their right mind would brake before a corner then accelerate flat-out all the way into it and around it. Most people probably do not even believe that is possible with a relatively high-powered motorcycle. Coming out of corners faster means less power is needed on the straights. A really high-powered motorcycle often needs to be ridden slower in corners. When you line-up for a race, you can see what the other guys are riding. The main thing is to avoid hitting another motorcycle in corners. If you get the handling and power correct, the speed differential in corners can be too high. Most motorcycles are not set-up to handle like that. The emphasis is usually on getting more horsepower at the expense of smooth delivery and less lean.
 
A very sweet running set up Nigel and seems you are pretty close to the tune you are seeking, as with the hard mount motor everything needs to be balanced right, I never ridden a well set up Seeley, but do know my Featherbed set up with my Commando motor, crank balanced at 72% is pretty close for my 850 motor, but with a 2S cam profile and major port work and open exhaust system all plays a part, big spark and carbs tuned right make one fun bike to ride, I wish I had the money to throw in Jims lighter rods and pistons and everything else, that Jim sells, but my set up is built for the road and it's been in the early 80s since I done track days out at a very tight Lakeside raceway here in my home town.
My set up works great, handles like it's on rails, has lots of torque and revs very freely, but sometimes I got to think Al's thinking is so far out, he seems to be an expert on Featherbed frames but has never owned one or rode one that is well set up, and of course HP as well a good handling frame will win races or be up there with the top riders, a bike is no good unless it has a good rider who knows his bike and how its set up, rider skill, bike set up as well a good motor all plays a major part, by the looks of things Nigel you have a very good understand of your workmanship, love to see it in action, less talk and more action is the way to go, not like some who are all talk and expert in everything except getting on the bike and riding, sorry Al, but I think Nigel is on a winner and knows his stuff, good on you Nigel, very entertaining and a joy to be watching.

Ashley
 
A gentlemen never tells, what about you though? ;)

What was the RPM threshold for the test runs? Sounded over 8000 RPM, and I figure you built it to do more.

I worry about doing this locally at a shop that specializes in fuel mapping for inline 4's. They wind the hell out of those engines on the dyno. I don't know if the young guys would be able to stop twisting the throttle at 7K RPM. Plus the gearbox is upside down and backwards shifting to them. I probably worry too much, but don't want to take home a blown engine after signing a service contract that probably says they are not responsible for anything.
 
Going back with the original poster of Fast E. and his response to my query.
Herb Becker used Don Morris to dyno test his engine for Doug MacRae's bike build back when he was still alive. R.I.P. We miss him.
Honest numbers.... not bullshit.
But I have heard numbers from other Ontario members that I thought were higher than expected for a street build. Just saying.
Cheers,
T
 
ashman said:
A very sweet running set up Nigel and seems you are pretty close to the tune you are seeking, as with the hard mount motor everything needs to be balanced right, I never ridden a well set up Seeley, but do know my Featherbed set up with my Commando motor, crank balanced at 72% is pretty close for my 850 motor, but with a 2S cam profile and major port work and open exhaust system all plays a part, big spark and carbs tuned right make one fun bike to ride, I wish I had the money to throw in Jims lighter rods and pistons and everything else, that Jim sells, but my set up is built for the road and it's been in the early 80s since I done track days out at a very tight Lakeside raceway here in my home town.
My set up works great, handles like it's on rails, has lots of torque and revs very freely, but sometimes I got to think Al's thinking is so far out, he seems to be an expert on Featherbed frames but has never owned one or rode one that is well set up, and of course HP as well a good handling frame will win races or be up there with the top riders, a bike is no good unless it has a good rider who knows his bike and how its set up, rider skill, bike set up as well a good motor all plays a major part, by the looks of things Nigel you have a very good understand of your workmanship, love to see it in action, less talk and more action is the way to go, not like some who are all talk and expert in everything except getting on the bike and riding, sorry Al, but I think Nigel is on a winner and knows his stuff, good on you Nigel, very entertaining and a joy to be watching.

Ashley
Click to expand...
Ashley, It is nice that you believe in your bike, And I think that if I'd had my 850 motor instead of my 500cc short stroke Triumph motor in my Featherbed frame, I would have done much better. However a Featherbed frame can never be as good as a Seeley. And you would probably find Seeley frames are excluded from races for Manx Norton and G50 Matchless and BSA Gold Star motorcycles. I have ridden 3 different Featherbed framed motorcycles. The best was the Manx Norton - I was not aware of the need for oversteer until I rode that. My mate's 650 Triton is neutral handling and faster in a straight line than the Manx. However I would beat it with the Manx - I could beat him with my 500cc Triton, however I used to race against him in All-Powers races, and I would never lower the gearing. If I was passed at the end of a straight by a much more powerful bike, they would be in front of me in the next corner and cause me to back-off. With the power-band my bike had, that was disastrous - I'd end-up going sideways.
 
You would have to be a pretty dud tuner if you did not get enough power out of a Commando engine to win races. It is like some other things - it does not matter how much you have got, it is what you do with it which counts. When you start racing with an unknown quantity, you need to adjust all the variables to get the optimum. One of the variables is the circuit upon which you race. I cheat - when I was a kid, I raced on both big and small circuits. Since Y2K, I have only raced on Winton and Mount Gambier circuits - they are similarly tight and small. So I do not struggle to adjust. With a Commando, the heavy crank stuffs throttle response in two ways - one is simply inertia, the other is the effect of inertia on carburation. If the throttle is ahead of the crank, the taper on the needles in the carbs richens the mixture too quickly, so you accelerate slower when coming out of corners. If you are not fast enough when coming out of corners, you need more horsepower as you go down the straights. Close ratio gears mean do not get ahead of the crank so often. When the crank is revving at 7,200 RPM and I race-change up, I always get a boost. I only ever lose about 500 RPM. My mate with the 650 Triton does not know how to race-change. I once rode his bike - he did not know it could go so fast. A bloke on a Kawasaki H2 two-stroke had a go at me and got done - he chucked it down the road behind me. The taper on the carb needles is more important than the size of the main jets.
 
Al I didn't build my hot 850 Featherbed for racing always for the road but it's no slouch when it comes to tight twisty roads with long straight to the next one, my motor will run very freely with the work I have done too it, when I built it I learned from others mistake with the set up, I built it right the first time and improved it when I had the money for better upgrades, 44 + years and it gets better all the time and its reliable.
 
Ashley, I was at an historic meeting a few years ago - across on the other side of the pits I could see a featherbed bike with an 850 Commando engine. It was probably being raced id Period 3 which has a cut-off date of 1963. It would have been an excellent way to have fun. That much torque would be lovely with a featherbed. I am pretty disgusted with historic racing. My interest in racing is more about developing, than winning races. My T250 Suzuki won too easily, so I sold it. If I find ways of making motorcycles faster, I usually share what I have learned. If we all go faster, we will have more fun.
 
If you watch Goodwood Revival - about 3 years ago, there were 3 MV500s. A Seeley G50 would have probably been better competition for them than Molnar Manxes.
 
Ashley, a race motorcycle on public roads is not a good way to go. When the unit construction T120 Bonnevilles came out in 1963, they were as fast in races as 500cc Manx Nortons. The handling thing is a puzzle. I have read papers from the Society of Automotive Engineers on motorcycle handling in which they admit they cannot draw any conclusions. I don't know where Colin Seeley got his smarts - nor the two McCandless brothers who developed the featherbed frame. The only reason my Mk 3 Seeley frame handles is I spoke to Rod Tingate who worked for Seeley, when he was in the UK helping Kim Newcombe with the Konig. He told me that all the Seeley frames have 27 degree rake. I used the Commando motor because Gus Kuhn was having success against Peter Williams. His bike might have been the one which Ken Blake was riding when he died on the IOM.
Because of my experience with my 500cc Triton, I knew the motor has to be as far forward as possible. The slope on the Commando motor probably helps your bike. Changes to a featherbed frame set-up are more critical.
 
Schwany said:
A gentlemen never tells, what about you though? ;)

What was the RPM threshold for the test runs? Sounded over 8000 RPM, and I figure you built it to do more.

I worry about doing this locally at a shop that specializes in fuel mapping for inline 4's. They wind the hell out of those engines on the dyno. I don't know if the young guys would be able to stop twisting the throttle at 7K RPM. Plus the gearbox is upside down and backwards shifting to them. I probably worry too much, but don't want to take home a blown engine after signing a service contract that probably says they are not responsible for anything.
Click to expand...
Just over 7k. I agree, it does sound like it’s doing more than that! But even at such modest revs I’m matching the rwhp I used to get out of my big 8 valve Nourish Dresda.

Peak power is actually below that. So under normal riding I only rev to 6k and even then will sometimes short shift in the lower gears as the low end torque is so good and the curve so flat, but it’s good to know I can hang on to revs if needed, and do so in total safety.

Folk do build ‘em to go to 8k, with consequently higher rwhp figures, to do that you need more compression.

Mines around 10.7:1, starts easily, and doesn’t really need revving beyond 6k. So it’s kinda deliberately on the mild side, which is ideal for a track day toy, and is already plenty fast enough for my needs and abilities !
 
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Fast Eddie said:
Just over 7k. I agree, it does sound more than that! But I’m matching the rwhp I used to get out of my big 8 valve Nourish Dresda.

Peak power is actually below that. So under normal riding I only rev to 6k and will sometime short shift in the lower gears as the torque is so good, but it’s good to know I can hang on to revs etc if needed in total safety.

Folk do build ‘em to go to 8k, to do that you need more compression.

Mines around 10.8:1, starts easily, and doesn’t really need revving beyond 6k. So it’s kinda deliberately on the mild side, which is ideal for a track day toy, and is already plenty fast enough for my needs and abilities !
Click to expand...
The crank balance factor probably limits how high you can rev the motor. My balance factor is 72% and my pistons are standard 850. I usually try to limit my revs to 7000 RPM, but usually see about 7300 RPM. It feels as though it wants to go to 8000 RPM - I just don't do that. With my bike, there is only the fuel tank above the motor, and that crank at high revs could easily kill. It has a lot of energy stored in it.
One thing you should never do is decry your own abilities. Expert rider stuff is bullshit - when somebody tours past you much faster, you have never usually experienced what their motorcycle does for them. Anyone could win a race with my Seeley 850, however they would need to be told how to use it - it is not obvious. Even thinking about it tends to worry me - it is not normal. I cannot imagine what might happen under various circumstances when using that technique. The speed differential in corners is too high, if somebody comes down from the high line.
I used to believe I was slow because I could not ride well enough. The really fast guys usually do not tell others why they are fast. I was interested in Casey Stoners' discussion about Turn 3 on Phillip Island on a GP bike. It was revealing. I would not like it.
Crashing hurts me as much as anybody else, but sliding down the road is usually harmless. I don't stick my head out in dangerous places. I don't usually experience fear when racing.
 
A balanced big journal bolt-up crank in a Triumph 650 willl rev to 8000 RPM all day without blowing-up. My mate uses one piece Triumph cranks in his Triton and only ever revs it to 6300 RPM, and is still fast enough - he tunes and gears for torque. My 500cc Triton had a 63mm stroke billet crank and the rev limit was 10,500 RPM - it was a bastard all power and no torque - it would go sideways almost without provocation. I would not like to ride a 500cc Paton on the IOM. To get it going that fast, it has to be dangerous. In the photos, it has megaphone exhausts. Many people have never experienced the effect that has in corners.
 
Basic engineering 101: Power = Torque x Omega ( rational speed in radians per second - divide rpm by 377 to get Omega )

So... no power without torque Al
 
Fast Eddie said:
Just over 7k. I agree, it does sound like it’s doing more than that! But even at such modest revs I’m matching the rwhp I used to get out of my big 8 valve Nourish Dresda.

Peak power is actually below that. So under normal riding I only rev to 6k and even then will sometimes short shift in the lower gears as the low end torque is so good and the curve so flat, but it’s good to know I can hang on to revs if needed, and do so in total safety.

Folk do build ‘em to go to 8k, with consequently higher rwhp figures, to do that you need more compression.

Mines around 10.7:1, starts easily, and doesn’t really need revving beyond 6k. So it’s kinda deliberately on the mild side, which is ideal for a track day toy, and is already plenty fast enough for my needs and abilities !
Click to expand...
Thanks, I appreciate the additional info. It's an impressive motorcycle.

I would like to build a 1007 with all the goodies just to do it and listen to it. Sounds of thunder is music for the soul.
 
Peak power is changed by exhaust system, cam timing and stroke. My 500cc short stroke triumph motor had a very dangerous power band. If I went into a corner hot behind other riders and was forced to back-off, it would go below the bottom and I would not have enough power to get around the corner. If I slipped the clutch to get more power, the bike would immediately go sideways. The motor had heaps of power up high, but getting it to pull when revving low was nearly impossible. I was trained by that motor - for me riding the Seeley 850 is dead easy. It never tries to bite me.
Torque wins races. Back in the early 1960s, two brothers had a pushrod ES2 Norton motor in what was originally a Manx. It was as quick as a Manx, but it was geared totally differently - they made it pull rather than rev. Some people believe two-strokes are peaky. My T250 Suzuki was a gem compared to that 500cc Triumph, and it was infinitely safer.
That 500cc Paton twin which has been raced against the MV500s, started as the Hannah Paton years ago - it would be a nasty piece of garbage. With megaphones, twins can be deadly. My Triton 500 was impossible to ride when it had megaphones. A two into one exhaust made it almost sensible. But changing cam timings did not do much.
 
There was only one genuine RC750 Honda which came to Victoria. Tony Cacciotti used to ride it. It had race cams and four megaphones. He told me he is much happier riding Rex Wolfenden's bikes which have 4 into 1 pipes. Getting more horsepower is easy, using it effectively is more difficult. My 850 motor still pulls when it is above 7000 RPM. The problem with a Commando engine is you do not know what you have until you raise the overall gearing, and with the heavy crank, you cannot afford to lose too many revs - close ratios help. The taper on the needles in the carbs also interacts. If they richen the mixture too quickly, the motor is slower.
 
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Schwany said:
A gentlemen never tells, what about you though? ;)

What was the RPM threshold for the test runs? Sounded over 8000 RPM, and I figure you built it to do more.

I worry about doing this locally at a shop that specializes in fuel mapping for inline 4's. They wind the hell out of those engines on the dyno. I don't know if the young guys would be able to stop twisting the throttle at 7K RPM. Plus the gearbox is upside down and backwards shifting to them. I probably worry too much, but don't want to take home a blown engine after signing a service contract that probably says they are not responsible for anything.
Click to expand...
The dyno operator at the Cabbage Patch (Daytona) couldn't even kick start my RZ350... he gave it long, slow kicks.
I asked him to shut down at 10,000 RPM, he went over 12,000
 


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