143MPH 850 MK1 Commando?

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Young Ron Wood pulled a bit of weight of the Flywheel , Steve . Would be common on any race machine . Maybe not quite so much of , for the Dirt .
The flywheel Effects what keeps it smooth , and the wheel spinning evenly . to light , and it'd STOP if you shut the Throttle .

The infernal CLUTCH assembly , and Wheel weight , being rotateing masses , are all relevant too . getting real scientific , The relevant masses
( proportion of total rotateing ) would be of some relavance .

These Ducati Bevels didnt allways run flywheels , and some suckers saying the D type ( Jag ) Le Mans , with its 3 plate ( multi plate ) clutch , ran no flywheel .
Infernal balance shafts are horrible contrivances in that respect . The Hamonics in the Cam Drive Gears , in the DFV Cosworth are what led young Kieth to go
a bit overboard with the Norton P95 Challenge . Brabam Repco V-8s had gear drive failure through harmonics in the G.P. engines also .

No a damn CAMSHAFT would be a sensible place to put a bit of flywheel ( mass ) except Top weight rolls a bike out of a corner , sideways on the dirt .
Much the same on Tarmac , Id suspect . Those sooper Bike suckers do mighty highsides if they cock it up .
 
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+1. Seems a tad personal. At least hobot is open to dialogue and admitting he might be wrong occasionally, not making accusations. I've noticed a lot of attitude towards Hobot and can't for the life of me understand it. Give respect to get it!
Thanx for giving me the benefit of doubt Snorton. I've no background to build an engine or chassis and never been in track competition so it urks the snot out of some on my reports but they are so polite and safe here compared to the attitudes and attempts of hots shots to put Peel in her place its part of my hobby now so tend to invite such reactions for what happens on shoot outs. Next Peel has many unknowns but handling beyond what anyone else is seen doing or describes ain't conjecture.

Appreciate a lot of what Matt posts on historical variations from factory and results. I've been warned off lightening flywheel but 4-5 lbs didn't bother stalling on let offs and seemed to help me break free of too much sideways traction. If ya can't break free in time then high sides too soon, on tarmac or THE Grit. If ya can't get sideways in time then can't slow down one direction of speed to convert into another by a controlled crash which is saved by instant torque hit that over powers and out races the bad reactions others seem to fear after pop up-cock ups. Peels crank with the welding plus bolts left in flywheel and bob wieghts came out about 25 lb so only 3-ish lb lighter. One fairly minor detail for the experts to pick on me is compression ratio also has an effect similar to BF, ie: higher CR is like higher BF as takes some to the vertical engine jump out by cushioning the rods and piston jerk at TDC. Also rpm tolerance aided with boost helping to shove piston down on intake. Isolastics don't seem to need any set zone of BF so I'm also the only one wondering about the BF effects on power pulse hook up both in leans and bee lines, especially climb outs.

I'm skinny as a stick so wind blast ain't hardly noticed til 120 then I have to hang on d/t air lift out of the saddle. Its not a constant at that speed so surprises ya as a gust flows over and air appears under my butt which lifts feet out of peg planting too. Some times its just a extra hump in the road, so 120 is where I mark hi speed handling starts. I've got a big fairing I can get behind but mostly for storage to commute and travel. I've seen photo of it on a Cdo but only one I saw up close mounted was being attracted to a bullet shaped profile of a race H2 at a rally to realize its was just like Peels. Hehe everyone perked up at its raspy gnarly start up, till the odors built up then grinned to hear it cruise by the parking lot up close, then got annoying each further low power pass. But it sure looked sleek. Peel gets ground effects lift/drop at her hi angles and speeds, I've not heard others complain about this, but has made me leave side covers off and conceive of training wheels on wing struts to off center and suck rear down as well as act as drag to keep rear from passing front as easy.
 
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Young BRITTEN had a few thoughts on Downforce . His original Aero D Zero being the winged wonder .

Heres a low friction Norton Twin . :D



Anyone wishing to retain the Hele Domiracer picture , put it on permanent wotsit , as Ive ' borrowed ' from Ebay .Despite ' not available ' at first attempt . :D
 
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Battle of Britten . :lol:



one for the Kamakazi kid .





NOW , WHERE were we . :?





thisisa fleabay onetwo .

 
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CONSPIRACY by Ear Plug Manufacturer & Hearing society . What do you call Dentists for EARS . :(





Didnt the wheels fall off , or Hogslayer chew it up or something . Volenteers for riders required , all queue here . :|
 
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Matt Spencer said:
Young BRITTEN had a few thoughts on Downforce . His original Aero D Zero being the winged wonder .

Heres a low friction Norton Twin . :D



Anyone wishing to retain the Hele Domiracer picture , put it on permanent wotsit , as Ive ' borrowed ' from Ebay .Despite ' not available ' at first attempt . :D
Picture shows two piston rings, from the information I have on this race engine it had only a single Dykes piston ring.
Or is that a single ring and oil ring :?:
 
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The final development Domiracer engine had a single compression ring and an oil control ring. A Dykes compression ring was talked about. It also had an alloy cylinder with plated bores, eccentric valve adjustment, bucket cam followers, 1.75" rod journals and use of needle bearings on various shafts.

So it would cool better than a Domi engine with an iron cylinder, could use a bit more compression and cam, and could rev a bit higher. But it was a works prototype and saw very little use outside it's successful IOM race. Throughout most of Doug Hele's investigation into the Domiracer project iron cylinders, 1.6" rod journals and standard rocker arms were used.

The successful production racing efforts of Bracebridge Street in the early 60s used stock-appearing bikes with some development goodies inside the engines such as the 1.6" cranks and bucket tappets.

Development Dominator engines with these works parts inside were built up into not only the lowboy frame, but also the standard Manx frame and the Daytona Slimline bikes, all with Manx wheels, tanks, forks etc.

A few 650cc racers were built as well as the 500cc bikes. A lot of other things were tried or in the "works" but disappeared when AMC eliminated the Norton works and began making Norton motorcycles elsewhere.

All this information is from either direct quotes of Doug Hele, still-existing hard parts, factory sponsored riders/tuners or period photographs.
 

lcrken

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Dances with Shrapnel said:
Anybody have more detailed illustrations or drawings or a few pictures of the bucket cam followers?
Caught your attention too, did they? I was just having the same sort of thoughts. Makes you wonder if they could be as light as the BSA lifter conversions for Commandos.

Ken
 
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Also noticed the pushrods coming into the cam follower tunnels rather oblique. Have an exagerated problem with our 500 ultra short stroke with the shortened barrel. Herb and I kicked this around and will revert back to the longer (Steve Maney) barrels on future builds. I think the engine also likes the extremely long rod to stroke ratio.

Looks like the subject 500 also has a pressure feed on the far end of the cam.

Back to the hollow bucket followers; they look like they are somewhat modeled after the factory followers.
 
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Did the F 750 J.P.N.s use Ti pushrods [ as BSA/Triumph did in their B 50MXs/factory experimental triples]?
& Matt, Boris Murray of double preunit Triumph dragbike fame [the inspiration for T.C. & crew] was the pilot for the Denco Kaw triple/triple H2..
 
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JPN racers were on a fairly limited budget, so be interesting if anyone knows the answer to this.

George Hunt has what he says is as near to a works 500cc Domiracer as can get (what does that mean ?) and it has a set of titanium pushrods.

Titanium parts are of course a lot more common (and affordable) now than they were were back then - EXPENSIVE was then the word.

Seem to have wandered a long way from fast road bikes....
 
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Rohan said:
Seem to have wandered a long way from fast road bikes....
No worries, the title of this thread is "143MPH 850 MK1 Commando?" :p

As for titanium pushrods, I have a gut feeling that would be a misapplication for higher loads. Most serious performance Commando builds with greater pushrod loading go with Chromoly for stiffness (big slenderness ratio) or aluminum for sectional stiffnesss and low weight.

Titanium has one third the modulus of steel with only 60% the mass of steel when compared to steel so in compression applications you need considerably more Titanium. It's really a similar case with Aluminum.

There was a fellow at Daytona a few years ago who was running carbon fiber pushrods in his Norton. He broke at least one during that venue and went running to the vendors to find a stock replacement. He had little windows with covers on the top on the top of the head to access the pushrods so that was probably not the first time he broke them.
 
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DwS , them there PUSHROD / Camfollwers are POSTED on the PROCEEDING PAGE .

NOW , whats noteworthy about this little sucker , is that its Lap Time , in 61 was FASTER than Pickerals in 67 on the Dunstall 750 in the SAME FRAME . therfore the 500 wasnt as slow as the 750 . :? :lol:
And theyre all PRODUCTION BASEd ,

Our Cyl head porting chap may well be intrested in the pictures of the roller ecentric rockers . Lampredi used ' Valve Springs ' ( coil ) over the CAM FOLLOWERS on one engine , and Hair Pin on the ROCKERS
of another , in addition to the springs on the valves . On those funny red cars . " Youre Ferraris falling to pieces , WHAt are you complaining about . YOU PAY FOR THE ENGINE , the rest of the cars free " :(
 
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Matt Spencer said:
DwS , them there PUSHROD / Camfollwers are POSTED on the PROCEEDING PAGE .(
Hells bells and buckets of blood mate. I may have skipped a cog - that's what happens when you step away for a blink. Thanks for pointing that one out.

Nice pieces of work. Are those the work of Heinz Kegler?

As for lap times, strange things happen out on the track.
 
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"As for lap times..." Indeed, Frank Perris J.P.N. team boss, disputes P.William's claim that the Mono was quicker than the space frame, he wrote that they were dimensonally [cycle-wise] identical, but the S-F weighed considerably less, & the clincher is in the lap charts which shows the S-F lapped quicker...
Incidentally, John Cooper couldn`t cope with the +15 hp drop from his trick BSA R3 - when he raced the J.P.N. bikes[he was faster on his 350 Yamsel], & prefered the `72 Commando based chassis of the lot.
 
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dunno Dances , theyre on IMAGESHACK , so going there and asking for , Er . . . might get the guys name 7 whatever else it is he's into .

Was at least two articals ( editorials ? ) in the blue M'c weekly , pic with Hele at his desk . ONE Im sure had Domiracer engine parts strewn across it .
Was just previous or about the time of the I.o.M. that year . jazzing things up as it were .

seen referance to that set up ' pushrods into bottom of followers ' elsewhere refering to maybe Dunstall , perhaps. May recall . :?

will throw you the Domi links , just in case . CHECK a the pm's . D.W.S. . :p
 
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Dances with Shrapnel said:
Also noticed the pushrods coming into the cam follower tunnels rather oblique. Have an exagerated problem with our 500 ultra short stroke with the shortened barrel. Herb and I kicked this around and will revert back to the longer (Steve Maney) barrels on future builds. I think the engine also likes the extremely long rod to stroke ratio.

Looks like the subject 500 also has a pressure feed on the far end of the cam.

Back to the hollow bucket followers; they look like they are somewhat modeled after the factory followers.
Re; "Also noticed the pushrods coming into the cam follower tunnels rather oblique"
Your eyes are not deceiving you the pushrods went right into the camfollowers and were located at the bottom –there was a picture on this website a while ago from the NOC website, but I cannot find it.

re; "Looks like the subject 500 also has a pressure feed on the far end of the cam."
The 500 racer had force fed needle roller bearing
 
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Dances with Shrapnel said:
Matt Spencer said:
DwS , them there PUSHROD / Camfollwers are POSTED on the PROCEEDING PAGE .(
Hells bells and buckets of blood mate. I may have skipped a cog - that's what happens when you step away for a blink. Thanks for pointing that one out.

Nice pieces of work. Are those the work of Heinz Kegler?

As for lap times, strange things happen out on the track.
Where have you been then :?:
they were on the works racer in 1961 :!:
 
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