Big valves or small valves

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For road bikes you need reliability. If you tune your bike to give maximum power, you often lose reliability. Tuning is often weather dependent. Modern road bikes have engine management systems which cope with changes in conditions. With a Commando, YOU are the EMS.
 
If the object is to find enough power to lift the front end, I'm not sure the Commando is a great candidate. I still have not seen a Norton Commando, big valves or small, properly power
lifting it's wheel off the pavement in anger, Maico 490 style. Somewhere I saw a vid showing a Commando rider jerking the bars up in anger, the front end did a weak lift.
Somewhere else the pogo stick routine was used with the suspension to get the wheel airborne, or both tricks at same time aka my Zook80 or Yamaha 100 twin jet.
Maybe Ken's 1007 will do the trick properly!



Glen
 
Forum police alert!!!

Seems like the distribution of weight is all wrong for doing wheelies on a stock Commando. Plus, a stock Norton is a lot heavier than a Maico 490. Jim's bike probably weighs 60lbs less than a stock Commando, which would give it a wheelie edge.

Like many I've owned a few bikes that would lift the front end to the sky without much throttle. My modified (oh no, did he say modified?) 86 GSXR1100 would do it in 5th gear at 130mph easily. Geared that one like a dirt bike and it still would do over 150mph. My Norton is not one that I could count on for a power wheelie of any kind. I have not put bigger valves in it. As is, it might do a 2nd gear power wheelie if I took the front brake off, but doing wheelies is not on my short list. Getting back home in one piece is though.

That reminds me. One time last summer when returning from a 300 mile Norton test ride. I noticed a young guy on a KTM single entering the HWY with the front wheel off the ground. He got on the HWY and kept the front wheel in the air for at least 2 miles. I gave him a big thumbs up when he let me get close to him. Then he was off again with the front end up in the air.

Off the rails I am.
 
Schwany said:
Forum police alert!!!

Seems like the distribution of weight is all wrong for doing wheelies on a stock Commando. Plus, a stock Norton is a lot heavier than a Maico 490. Jim's bike probably weighs 60lbs less than a stock Commando, which would give it a wheelie edge
Click to expand...
They just don't have enough grunt for that kind of silliness.
Although I could be proven wrong at any moment.
Perhaps we should start a thread, " Show us your Commando Wheelie"
Some folks get very upset by such carrying on, so maybe not.
I recall a thread some years ago where a fellow had attempted a takeoff clutch wheelie on this 880 Dreer. We could probably manage a clutch wheelie on a stock MK3, so it should be easy on a Dreer 880.
The wheelie was for the benefit of a group of onlookers/ fans of the bike.
Just as the front wheel lifted the crank broke and a conrod poked a large hole in the bottom of the crankcase, oil everywhere . Most importantly, there wasn't a proper sustain on the wheelie!

Glen
 
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worntorn said:
They just don't have enough grunt for that kind of silliness.
Although I could be proven wrong at any moment.
Perhaps we should start a thread, " Show us your Commando Wheelie"
Some folks get very upset by such carrying on, so maybe not.
I recall a thread some years ago where a fellow had attempted a takeoff clutch wheelie on this 880 Dreer. We could probably manage a clutch wheelie on a stock MK3, so it should be easy on a Dreer 880.
The wheelie was for the benefit of a group of onlookers/ fans of the bike.
Just as the front wheel lifted the crank broke and a conrod poked a large hole in the bottom of the crankcase, oil everywhere . Most importantly, there wasn't a proper sustain on the wheelie!

Glen
Click to expand...
Glen,

I think you get a free pass. I'm still working on my secret handshake merit badge.

I like the edit with the bottom end breaking.

I'll never get on the wall of wheelies. I'd rather baby it off the line so to speak. It's geared up in the primary, so not a good candidate for wheelies anyway.
 
worntorn said:
If the object is to find enough power to lift the front end, I'm not sure the Commando is a great candidate. I still have not seen a Norton Commando, big valves or small, properly power
lifting it's wheel off the pavement in anger, Maico 490 style. Somewhere I saw a vid showing a Commando rider jerking the bars up in anger, the front end did a weak lift.
Somewhere else the pogo stick routine was used with the suspension to get the wheel airborne, or both tricks at same time aka my Zook80 or Yamaha 100 twin jet.
Maybe Ken's 1007 will do the trick properly!



Glen
Click to expand...
I've seen a few cases of riders on Commandos doing serious wheelies, so it's certainly possible. I only recall one Commando of mine that lifted the front wheel easily. After I converted my PR to a 920 cc AMA Pro Twins racer, I found that with it geared down for the shorter circuits, it would carry the front wheel at the start every time, even with fairly gentle clutch and throttle coordination. It was enough that I had to either short shift or just roll off a little to get it back on the ground. It would do the same some times during a fast shift into second with wide open throttle. I'm sure it would have done a proper wheelie in skilled hands, but I wasn't interested in practicing wheelie techniques, just trying to get around the track quicker. Getting the bike up on the back wheel is more about technique than big horsepower. Not saying that big horsepower doesn't make it easier, just that it's not required. I never developed the wheelie skills, it's just not my shtick, but I've watched one of my friends wheelie all sorts of bikes over the years, some with way less horsepower than the Commando.

Ken
 
If you use the clutch agressively or shift hard ( clutch again) etc just about any bike will lift the front wheel.
It takes a lot of power to do it simply by rolling on the throttle, especially after first gear.

We are bang on topic.
The question is- will big valves yield big (throttle)wheelies? :)


Glen
 
Last edited:
worntorn said:
We are bang on topic.
The question is- will big valves yield big (throttle)wheelies? :)


Glen
Click to expand...

The 'Stone video suggests a small port, small valve pre 1971 drum brake 750 Commando had no trouble doing sustained accelerating wheelies (based on the angle) with a skilled rider.
 
I think I owe @alcotrel an apology. In my desire to show my interest and respect to Jim and his expertise, I showed a disrespect to Al and his viewpoint.

Sorry about that everyone.
 
t ingermanson said:
I think I owe @alcotrel an apology. In my desire to show my interest and respect to Jim and his expertise, I showed a disrespect to Al and his viewpoint.

Sorry about that everyone.
Click to expand...

Its the Internet. (Just saying as they say)
Just don't ask about 850 top ends on 750 cases.
 
Time Warp said:
The 'Stone video suggests a small port, small valve pre 1971 drum brake 750 Commando had no trouble doing sustained accelerating wheelies (based on the angle) with a skilled rider.
Click to expand...
They are using the clutch and flywheel momentum like crazy in that movie. Sorry, those are Zook 80 wheelies, they don't count. Not as throttle wheelies anyway.
I think Ken is still our best hope, we just have to convince him to have a "Hold my beer" moment

Glen
 
Big valves or small valves
 
Sir Eddy at Westwood isn't it?
My friend Murray Neibel has that photo on his website.
Murray also raced at Westwood in those days.
I don't know if it's a throttle wheelie or a hard shift with bum well back, but it looks good!
Big valves or standard?

Glen
 
worntorn said:
Sir Eddy at Westwood isn't it?
My friend Murray Neibel has that photo on his website.
Murray also raced at Westwood in those days.
I don't know if it's a throttle wheelie or a hard shift with bum well back, but it looks good!

Glen
Click to expand...
Yes Sir!
One of my favorite! They called it Deer's Leap. The track had a crest in it and if you could carry enough speed you would launch as you crest the hill.
 
My 920 front wheel skips the surface if I'm driving it hard out of turns . Of the start the rear will step, that nice gentle weave as you go forward. If under throttle in second you pull back on the bars you could wheelie. In the Seeley frame it wont. Which is nice as it's nothing I want or like. Not with my Toprak style riding skills & heavy feet.
 
Son of Siredward said:
Yes Sir!
One of my favorite! They called it Deer's Leap. The track had a crest in it and if you could carry enough speed you would launch as you crest the hill.
Click to expand...
A number of the group I hang with are oldtime Westwood racers.
They often talk about going very, very fast over Deer's Leap.
Sometimes I think they have applied annual inflation rates to their Deer's Leap claimed speeds as the numbers seem to get remembered a bit higher every year:)

Glen
 
worntorn said:
A number of the group I hang with are oldtime Westwood racers.
They often talk about going very, very fast over Deer's Leap.
Sometimes I think they have applied annual inflation rates to their Deer's Leap claimed speeds as the numbers seem to get remembered a bit higher every year:)

Glen
Click to expand...
I was talking with an old-timer recently
He reckons when he bought his Daytona (old Daytona not the thaiumph one) that's once run in it would lift the wheel in the first 3 gear's :rolleyes: :D :D
 
worntorn said:
If the object is to find enough power to lift the front end, I'm not sure the Commando is a great candidate. I still have not seen a Norton Commando, big valves or small, properly power
lifting it's wheel off the pavement in anger, Maico 490 style. Somewhere I saw a vid showing a Commando rider jerking the bars up in anger, the front end did a weak lift.
Somewhere else the pogo stick routine was used with the suspension to get the wheel airborne, or both tricks at same time aka my Zook80 or Yamaha 100 twin jet.
Maybe Ken's 1007 will do the trick properly!



Glen
Click to expand...
If the bike's weight distribution is correct for the power of the motor, the bike should be spinning it's back wheel before the front lifts. There is omly one corner on Winton Raceway which is slow enough to get my rear wheel slipping as I accelerate out of it. It is a hairpin. You don't get many of those on public roads.
 
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