Commando Top Speed? (2010)

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Hobot's Commandos are unlie any others in that thier rider instills confidence in the bike, instead of the other way around. The result is performance heretofore unknown to motorcycling, especially Japanese motorcycling!
 
I've always considered myself a fairly competent tuner but I have never had a Norton (or any parallel twin) make the type of top end numbers that some guys here are claiming.

I have no idea how fast my current 850 will go. When holding it wide open and cooking along, the speedo needle is bouncing somewhere in between 90 and 120. I just split the difference and say that it goes 105.
 
Here's Fred Eiker's Nitros Nort and the 1000cc Harley he is trying to beat. They are tied at 155mph. No one is just dicking around at this game. Freds Nort will be using JS lightweight 920cc pistons/rods and our stage 2 cam with lightweight radiused type lifters (check out the fat lobes).

Jim S

Commando Top Speed? (2010)


Commando Top Speed? (2010)


Commando Top Speed? (2010)


Commando Top Speed? (2010)
 
Mark said:
I've always considered myself a fairly competent tuner but I have never had a Norton (or any parallel twin) make the type of top end numbers that some guys here are claiming.

I have no idea how fast my current 850 will go. When holding it wide open and cooking along, the speedo needle is bouncing somewhere in between 90 and 120. I just split the difference and say that it goes 105.
Click to expand...

Depends a lot on the dyno and how it is set up. I have found the factory calibration between a Superflow dyno and a Dynojet dyno to vary as much as 15%. The guys at Supeflow gave me different correction figures to use to make the numbers you get from my Superflow comparable to what you see with a Dynojet.
In the end the numbers you get don't mean shit except when you are comparing modifications on the same bike on the same dyno with the same operator. You can vary the readings in a big way just by using different air pressure in the tires or tying the bike down different. Jim
 
jseng1 said:
Here's Fred Eiker's Nitros Nort and the 1000cc Harley he is trying to beat. They are tied at 155mph. No one is just dicking around at this game. Freds Nort will be using JS lightweight 920cc pistons/rods and our stage 2 cam with lightweight radiused type lifters (check out the fat lobes).
Click to expand...

Well, what's it going to be, APG, or APF?

Not an insignificant difference between Gas and Fuel!

Niether one looks vegetarian to me...
 
comnoz said:
Depends a lot on the dyno and how it is set up. I have found the factory calibration between a Superflow dyno and a Dynojet dyno to vary as much as 15%. The guys at Supeflow gave me different correction figures to use to make the numbers you get from my Superflow comparable to what you see with a Dynojet.
In the end the numbers you get don't mean shit except when you are comparing modifications on the same bike on the same dyno with the same operator. You can vary the readings in a big way just by using different air pressure in the tires or tying the bike down different. Jim
Click to expand...

Amen. A voice of reason here. There have been so many numbers thrown around in this thread it's silly.

I have a dyno in my shop. I know what I can get at the rear wheel of my race bike (and street bike), and I'm not talking big numbers... quite the contrary. I use the numbers I get from the dyno as a benchmark. That's all. If I make a change and the power goes up, then I'm happy. Proof is in the pudding, and I'll serve it up anytime.

And further - brake horsepower (bhp) IS NOT rear wheel horsepower (rwhp). BHP is measured at the crank before parasitic loss from the drive train. No such thing as XXbhp at the rear wheel.
 
Anymore the measurement I look at on my own bike most is thrust. I have a sensor on the front wheel mount that measures the actual push of the bike in pounds. I dial in just enough force with the electric brake to slow the acceleration. The thrust output gets charted along with the drum speed in MPH or engine speed in RPM. It gives a very repeatable reading that isn't affected as easily by tires and traction. It works well for comparing before and after. You can also set the electric brake to hold a specific RPM and then adjust timing or fuel mixture on the fly to where maximum thrust is seen. Jim
 
comnoz said:
Anymore the measurement I look at on my own bike most is thrust. I have a sensor on the front wheel mount that measures the actual push of the bike in pounds. I dial in just enough force with the electric brake to slow the acceleration. The thrust output gets charted along with the drum speed in MPH or engine speed in RPM. It gives a very repeatable reading that isn't affected as easily by tires and traction. It works well for comparing before and after. You can also set the electric brake to hold a specific RPM and then adjust timing or fuel mixture on the fly to where maximum thrust is seen. Jim
Click to expand...

Sounds like a pretty smart idea to me, I would really like to know more about this.
Any pics of your setup?

.
 
Mark said:
comnoz said:
Anymore the measurement I look at on my own bike most is thrust. I have a sensor on the front wheel mount that measures the actual push of the bike in pounds. I dial in just enough force with the electric brake to slow the acceleration. The thrust output gets charted along with the drum speed in MPH or engine speed in RPM. It gives a very repeatable reading that isn't affected as easily by tires and traction. It works well for comparing before and after. You can also set the electric brake to hold a specific RPM and then adjust timing or fuel mixture on the fly to where maximum thrust is seen. Jim
Click to expand...

Sounds like a pretty smart idea to me, I would really like to know more about this.
Any pics of your setup?

.
Click to expand...

I will get one. Jim
 
Here is a picture of the thrust sensor.
Commando Top Speed? (2010)


The gauge at the top left is the bridge that reads the guage. The output from that goes to a serial port on a PC.
The gauge below that is the engine case temp gauge. I am holding the sensor in my hand.
Commando Top Speed? (2010)


Here is the dyno control stack with 3 PCs, the brake control, a 5 gas and the Superflow box.
Commando Top Speed? (2010)


Sorry for the fuzzy photos, My camera doesn't like the florescents. Come down to Pueblo and you can see it in person. Jim
 
comnoz said:
Depends a lot on the dyno and how it is set up. I have found the factory calibration between a Superflow dyno and a Dynojet dyno to vary as much as 15%. The guys at Supeflow gave me different correction figures to use to make the numbers you get from my Superflow comparable to what you see with a Dynojet.
In the end the numbers you get don't mean shit except when you are comparing modifications on the same bike on the same dyno with the same operator. You can vary the readings in a big way just by using different air pressure in the tires or tying the bike down different. Jim
Click to expand...

So there you have it, from an experienced engine tuner. From what little first hand experience I've had of dynamometers, I could not rely on the absolute figures they gave. As an example, my 996R Ducati gave a reading of 136 hp on a Dynojet dyno and not long after that, on another dyno in another country, gave a reading of 127 hp and nothing had been changed in the meantime. I find them very useful as rolling roads, though. There is a mobile dyno at many of the Irish national events and the operator knows what he's doing and he's doing it all the time. It saves a lot of time for the mechanics and even the classics have benefitted.
 
There has abeen a lot of discussion over whether fitting a heavier engine flywheel or heavier rear wheel would alter the power readout of a rolling road dyno.

Or whether using a form of "glue" to lightly stick the rear tyre to the rollers would alter the readings - likewise if tyre compounds even would alter the readings...

??
 
A lighter flywheel will obviously affect the acceleration rate of an engine and depending on the inertia factor it may show more horsepower on an inertia dyno. It will make an engine sound hotter for sure.

A lighter than stock will not show more steady state horsepower and may even show less power at a steady RPM . It is also questionable as to whether it will make a bike faster on the track. Some people swear by it but personally I have not found it was true for me on my own bike. My experience shows Norton got the crank weight about right. The new crank for my motor is a couple lbs. heavier than stock as it makes for a smoother motor. I doubt that going heavier will affect steady state horsepower in a measurable way although it may show less power on an inertia dyno with a light drum. Jim

And yes tire compounds and even the tread desigh will change chassis dyno readings a little bit.
 
From your posts on here, it seems pretty clear that your "wrist action" is highly developed!
Click to expand...

Taunt all ya like I'm serious as can be about Ms Peel and me getting to point there ain't no effect from other controls but throttle effect on rear tire for braking and twisting on CoG and launching into and out of turns. There are phases where controls reverse, brakes change lean, forks control traction and throttle blips slow while throttle cuts sharply accelerate. That's part of the low effort fun of a truly Neutral handing chassis just R wrist doing most the work so lungs-heart can catch up between wrist action. I was pleased with how rheostat direct to traction Peel's engine responded with ordinary Miki mouse or Amals - rather better than my SV650 or Ninja 900 when any throttle twitch makes or breaks leaned to max thrust. I can't hardly fall asleep at times flashing back on taking it to the edge of ordinary limits of two tire traction then nail it to break free and really fly around turns. I don't flashback on the antics I did or do on modern sports bikes skipping out front or rear or both so easy so soon its just not fun for the crisis recoveries that get thrust on me harshly for so little extra speed or G thrill, pashaw. Don't fret none Peel will have enough power to out run her tire ratings unless I shave em good and stay off the marbles and arrow heads.

Comoz, for my own sanity and sneers of those like Carbonfibre monitoring has been a large part of last few years searching shopping. Your road going dynometer is super intrguing duh. Think you could walk talk and sell into our own DIY power comparing and sharing units? Do ya have a unit to lease?
I have G-Force type accelerometer units but it make assumptions too.
 
grandpaul said:
Well, what's it going to be, APG, or APF?

Not an insignificant difference between Gas and Fuel!

Niether one looks vegetarian to me...
Click to expand...

Fred first ran the bike at Bonneville in 2008 in the 1000-APG class. That's when he was competing against bikes like the 1000-APG Harleys. The current record in the class is held by a Guzzi at 150.908 mph. The picture below shows the bike's configuration then.

Commando Top Speed? (2010)


In 2009 he made a lot of changes to the bike, and added nitrous oxide to run in 1000-APF. The bike was then in the configuration shown in Jim's post above. In 2010 they came back and again ran in 1000-APG, but with bigger nitrous jetting. They are planning to be back in 2011 with some more changes, including taking the engine up to 920 cc with Jim Schmidt's kit, fitting larger nitrous bottles, and probaly running a bigger nitrous shot, to try for some serious speeds, still running in 1000-APG. Should be pretty entertaining. The current record for the class is held by a Harley at 155.722 mph. That's the one Fred tied last year.

Ken
 
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