Dyno run (2017)

Brooking 850 · Dec 26, 2017

Alan, how long since you have ridden and or raced your bike?
Most of the guys commenting on the forum seem to be very pro active, active being the operative word.
Get your bike out, run it , race it and then give us some positive feed back please, I am genuinely keen to see how it goes amongst your peers.
there is a big race meeting in March at Eastern Creek , lots of bikes coming over from NZ, so be a good time to punt it.
Regards Mike

Fullauto · Dec 26, 2017

That's it Alan. I'm taking more notice of the fuel/air gauge these days. I'm going out in the late afternoon so that I can see it and try to use the closest freeways where I can play with the throttle a bit without running into anything. The improvement in fuel consumption as well as the smoother pick up from off idle has made the exercise very worthwhile. The bike will pick up from lower revs cleanly, idle is more even and generally runs beautifully. The only hiccup is that starting can still be hit and miss. I'm getting to that. The bike is being picked up in 6 days for the Philip Island trip, but I'm pretty happy about where I'm at with it.

splatt · Dec 26, 2017

Starting hit or miss

Do you find it usually starts first or second kick and then sometimes 45 kicks ?, if mine fires but fails to keep running I may as well quit it seems to flood up real quick

Hobot · Dec 26, 2017

Old tractor chain saw trick is heating the plugs pretty hot before next try. Some time a spriz of something highly combustible too. If that don't do it ya got more issues than just climate. Might raise float level a tad past getting pilot jet to idle best at carb manual spec. Maybe plug heat range a bit cold side? Maybe plug electrode angle deflecting kick velocity mixture to think about. A good gal should not need much foreplay or pampering to get started.

Fullauto · Dec 27, 2017

hobot said:
Old tractor chain saw trick is heating the plugs pretty hot before next try. Some time a spriz of something highly combustible too. If that don't do it ya got more issues than just climate. Might raise float level a tad past getting pilot jet to idle best at carb manual spec. Maybe plug heat range a bit cold side? Maybe plug electrode angle deflecting kick velocity mixture to think about. A good gal should not need much foreplay or pampering to get started.

Not really practical for day to day use. I'm sure I'm very close now.

acotrel · Dec 27, 2017

Brooking 850 said:
Alan, how long since you have ridden and or raced your bike?
Most of the guys commenting on the forum seem to be very pro active, active being the operative word.
Get your bike out, run it , race it and then give us some positive feed back please, I am genuinely keen to see how it goes amongst your peers.
there is a big race meeting in March at Eastern Creek , lots of bikes coming over from NZ, so be a good time to punt it.
Regards Mike

The only real hope I have of racing in the near future will be at the Austin7 meeting at Winton in May. Another alternative is the Old Farts meeting at Broadford which I think is in March. But I don't think my monetary situation will have improved enough by then. The Winton meeting has got too much bullshit associated with it, but is probably a better option because the guys who are worth beating will be there.

acotrel · Dec 27, 2017

Fullauto said:
That's it Alan. I'm taking more notice of the fuel/air gauge these days. I'm going out in the late afternoon so that I can see it and try to use the closest freeways where I can play with the throttle a bit without running into anything. The improvement in fuel consumption as well as the smoother pick up from off idle has made the exercise very worthwhile. The bike will pick up from lower revs cleanly, idle is more even and generally runs beautifully. The only hiccup is that starting can still be hit and miss. I'm getting to that. The bike is being picked up in 6 days for the Philip Island trip, but I'm pretty happy about where I'm at with it.

Ken, tuning your bike on a freeway might not be the best option. What you probably need is a loop of quiet back-roads with a lot of bends which force you to change up and down through the gears a lot. When I was a kid, we had the option of practising at Calder Raceway, however I would never do that. On public roads, there is always the problems of police and other traffic. So you can never really get into using the bike to it's fullest extent. These days I can practise at Winton, but the costs are prohibitive. So I rely on remembering what I did the last time I was there. It is amazing how much better a bike can be when you get it set up right.

Fullauto · Dec 27, 2017

acotrel said:
Ken, tuning your bike on a freeway might not be the best option. What you probably need is a loop of quiet back-roads with a lot of bends which force you to change up and down through the gears a lot. When I was a kid, we had the option of practising at Calder Raceway, however I would never do that. On public roads, there is always the problems of police and other traffic. So you can never really get into using the bike to it's fullest extent. These days I can practise at Winton, but the costs are prohibitive. So I rely on remembering what I did the last time I was there. It is amazing how much better a bike can be when you get it set up right.

Not a problem on a quiet day on the roads here, Alan. I think the starting issue is just final tweeking of the mixture screw. Best running was 2.5 turns out but a half turn in seems better for starting. You will see for yourself when you ride it!

ausnorton · Dec 27, 2017

I run a standard 850 mk3 with VM34 . It was running fine and then started taking a long time to idle properly , having to keep the choke in for longer than normal . I cleaned out the pilot jet and tweaked the air screw in a quarter turn at a time to make the idle a touch richer . It now idles real good , so you are on the right track I think .

Fullauto · Dec 28, 2017

ausnorton said:
I run a standard 850 mk3 with VM34 . It was running fine and then started taking a long time to idle properly , having to keep the choke in for longer than normal . I cleaned out the pilot jet and tweaked the air screw in a quarter turn at a time to make the idle a touch richer . It now idles real good , so you are on the right track I think .

Coming to PI for the Island Classic?

acotrel · Dec 28, 2017

Fullauto said:
Not a problem on a quiet day on the roads here, Alan. I think the starting issue is just final tweeking of the mixture screw. Best running was 2.5 turns out but a half turn in seems better for starting. You will see for yourself when you ride it!

Will you be bringing your panel-beating kit with you ?

gortnipper · Dec 28, 2017

Ken you should take it to a fun day at the track. I spent today on the new long International track at Hampton Downs. Albeit on the Duc as the Norton motor is not broken in to thrash yet. It was a hoot.

Fullauto · Dec 28, 2017

gortnipper said:
Ken you should take it to a fun day at the track. I spent today on the new long International track at Hampton Downs. Albeit on the Duc as the Norton motor is not broken in to thrash yet. It was a hoot.

Sorry, I don't do racetracks. I get my jollies on the road. I'm doing a run up to Mittagong to see an old friend of ours and then back to Melbourne. The bike needs to stay in ridable condition or I'm on the bus!.

MexicoMike · Nov 10, 2018

Interesting HP numbers. I have been kicking around buying one of the new Royal Enfield 650 twins for running around in the UK when we are there but I was worried about the fact that they have only 47HP rating. But since my totally stock engined Norton is acceptable power-wise, sounds like the RE should be able to at least match it since it probably has around 38-40 at the rear wheel. Based on the 45HP of the first post with the better head/cam, I would assume (hope?) a stock 850 Norton would at least manage 38-40.

My other serious thought was a new Kawasaki Z900RS or RS Cafe (111 HP advertised, 97 on a dyno)

Does anybody have Commando dyno numbers from back in the day when the factory advertised 60HP?

comnoz · Nov 10, 2018

MexicoMike said:
Interesting HP numbers. I have been kicking around buying one of the new Royal Enfield 650 twins for running around in the UK when we are there but I was worried about the fact that they have only 47HP rating. But since my totally stock engined Norton is acceptable power-wise, sounds like the RE should be able to at least match it since it probably has around 38-40 at the rear wheel. Based on the 45HP of the first post with the better head/cam, I would assume (hope?) a stock 850 Norton would at least manage 38-40.

My other serious thought was a new Kawasaki Z900RS or RS Cafe (111 HP advertised, 97 on a dyno)

Does anybody have Commando dyno numbers from back in the day when the factory advertised 60HP?

A good stock 74 850
37-38 on a Superflow
40-41 on a Dynojet

MexicoMike · Nov 10, 2018

Thanks Jim. So it's probably around the same as the 650 Royal Enfield twin! I base the guess re dyno numbers for the RE twin on the RE Continental GT 500 single which, per RE had 29 HP but on a dyno at Hitchcocks in the UK showed 21.

FWIW Hitchcocks have a mod kit that can get 40+ dyno HP from the same engine.

Around 3000 bucks

Heck, a Manx Norton single made more power than that 50+ years ago...

acotrel · Nov 10, 2018

I have ridden an excellent Manx Norton. My 850 is much faster.

comnoz · Nov 10, 2018

MexicoMike said:
Thanks Jim. So it's probably around the same as the 650 Royal Enfield twin! I base the guess re dyno numbers for the RE twin on the RE Continental GT 500 single which, per RE had 29 HP but on a dyno at Hitchcocks in the UK showed 21.

FWIW Hitchcocks have a mod kit that can get 40+ dyno HP from the same engine.
Around 3000 bucks

Heck, a Manx Norton single made more power than that 50+ years ago...

I don't know for sure, but I would suspect the Norton has more torque so it would probably feel stronger.

Matchless · Nov 10, 2018

I find it hard to believe that a 1974 850 only makes around 40 hp at the wheel. My '74 850 is mildly tuned, 920, PW3, Fullauto head & makes 63 RWHP on a Dyno Jet. I would have thought 47 ish for a stock bike. Wally Wyatt managed 58 hp on one of the AMC engine dynos for an Atlas motor, which then became a 750 Commando.

comnoz · Nov 10, 2018

Earlier years made a little more.
The figures I quoted were a 74-850 with the baffled ham can and the restricted peashooters.
A stock MK3 did about the same.
Of course if you open up the mufflers and airbox and rejetted the carbs you could get a good increase in horsepower, but only a little change in the torque.

Dyno run (2017)

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