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John Stevenson
07-26-2008, 06:14 AM
Who made the first motorcycle 8 valve twin cylinder DOHC engine and when ?

No prizes but I think you will have a suprise.

.

Doc Nickel
07-26-2008, 06:26 AM
Easy, the Honda NR750. They made room for eight valves by using some oddball oval pistons, with two rods each. It was basically a V-8 with each pair of cylinders siamesed.

As I recall that was back in the early eighties. I don't remember the specifics, or how well it did in the races (it was a pure race bike) but I know they released a very limited number of street versions, which sold for some truly absurd amount of money- like $100K or more.

Gorgeous bike, I'd have loved to have one, but it's one of those things you really shouldn't ride even if you can afford it. :)

Doc.

Charles Ping
07-26-2008, 07:27 AM
It must be the Hurley Pugh

http://www.hurley-pugh.co.uk

For anyone close to prewar British bikes that site is worth reading

Rustybolt
07-26-2008, 08:15 AM
Is it Vincent?

Evan
07-26-2008, 08:33 AM
Easy, the Honda NR750. They made room for eight valves by using some oddball oval pistons, with two rods each. It was basically a V-8 with each pair of cylinders siamesed.

Hardly. Honda made a DOHC 4 valve per cylinder twin racer in 1959, the Honda 125cc Twin, took 6th at the Isle of Man TT.

The one I want is the Honda 50cc Factory Racer. It was legendary in the 60s as it could do 100 mph. I could ride that here without license or insurance as it is only 50cc and falls in the "limited speed motorcycle" category. All the regulations here are based on displacement, not horsepower. The 50 racer was a twin and revved to around 20,000 rpm. :D

John Stevenson
07-26-2008, 08:48 AM
The one I want is the Honda 50cc Factory Racer. It was legendary in the 60s as it could do 100 mph. I could ride that here without license or insurance as it is only 50cc and falls in the "limited speed motorcycle" category. All the regulations here are based on displacement, not horsepower. The 50 racer was a twin and revved to around 20,000 rpm. :D
23,000 actually Evan.
Had one here once, at least the crank out of one to press it apart for a new big end bearing, my press wouldn't take it so took it round to ZF Gears to use their big press.
Got it to 87 tonnes and bottled out, too much was creaking and groaning, gave it back to the guy as it was.

These early racers are very rare, there are a few Honda's about but Suzuki and Yamaha used to take theirs about 5 miles offshore and dump them in the pacific so no one could have access to them.

Somewhere I have pictures of one of the 350 Honda twins that managed to 'escape' but they smashed every fin off the barrels and broke every casting.
I spent hours making and welding new fins on.
It probably would have been cheaper to have new cast but the guy wanted it 'original'.

.
PS Nice one Charles,not seen that site for a while.

.

Evan
07-26-2008, 08:59 AM
My first bike was a Honda 50. I spent many hours tuning and fiddling with it. A friend of mine had a very early prototype Honda 305 Superhawk, all tube frame. It would burn rubber for half a city block except every time he pulled that trick he had to replace the chain tension adjusters on the rear axle as they ended up bent in a U shape. :D

bob308
07-26-2008, 09:12 AM
harley in the 20's i think it was a boardtrack bike.

topct
07-26-2008, 09:49 AM
Is that eight valves per engine or cylinder?

If it's per cylinder I'd go with the Honda NR750.

I heard a rumor that their process for boring the oval cylinder is still a secret.

Harley did build an eight valve v-twin in the twenties. It was very fast. It could do over 120 on the mile dirt tracks. Braking was done with a compression release. It was an OHV however. And not the first.

Forgot to mention that they were still using clincher tires on that Harley.

John Stevenson
07-26-2008, 11:13 AM
Is that eight valves per engine or cylinder?


Ooops should have included the word twin in the title, so we are looking at 4 valves per cylinder.
Doc got a right answer, don't know if it was the first or not but it wasn't the one I was looking for.

.

Alistair Hosie
07-26-2008, 11:49 AM
Gordon Brown our prime minister said the Indian's are making a car brand new on the road for a thousand pounds don't know anything about it but talk about global warming they reckon a million will be sold in India alone.Alistair

John Stevenson
07-26-2008, 01:15 PM
Sorry Alistair it wasn't Gordon Brown.

.

topct
07-26-2008, 04:24 PM
1983, Triumph

"TSS-engined T58-1 with rubber-mounted, eight-valve engine aimed at police use is designed. The TR6 is reduced to 600cc. A prototype water-cooled, 900cc bike called the Phoenix (the engine was also known as the 'Diana') is designed in early 1983 (a water-cooled, twin OHC vertical twin)."

Doc Nickel
07-26-2008, 05:55 PM
Ooops should have included the word twin in the title, so we are looking at 4 valves per cylinder.
Doc got a right answer, don't know if it was the first or not but it wasn't the one I was looking for.

-Ah, see, you didn't say that. :D

To me, when somebody says "four valve" or "five valve", it's assumed you're referring to "per cylinder". That's why I thought the question was suspiciously easy, since Honda's oval setup is pretty much the only way you're going to get room for eight valves per bore.


Hardly. Honda made a DOHC 4 valve per cylinder twin racer in 1959, the Honda 125cc Twin, took 6th at the Isle of Man TT.

-Hardly what? The NR had eight valves per cylinder, which is what I thought John was asking. Eight valves total, for an unspecified-at-the-time twin? I couldn't say, but you're right, it was way earlier than the NR.

Doc.

bob ward
07-26-2008, 06:09 PM
Peugot in the early 1900s?

Evan
07-26-2008, 06:17 PM
The NR had eight valves per cylinder, which is what I thought John was asking.

And I thought he was asking about the engine, which he was.

torker
07-26-2008, 06:22 PM
Ok..so that 50cc Honda that did 23,000 rpm...I'm assuming it'd be a 4 cycle engine??? If it was..then how in the heck did they get the valves to work that fast? You'd have a hard time doing that with traditional type valve train..no?
Russ

topct
07-26-2008, 06:47 PM
Ok..so that 50cc Honda that did 23,000 rpm...I'm assuming it'd be a 4 cycle engine??? If it was..then how in the heck did they get the valves to work that fast? You'd have a hard time doing that with traditional type valve train..no?
Russ

The valves were very tiny. :D

torker
07-26-2008, 07:17 PM
Showin off your motors.. if I wasn't so sore..I'd go take a pic of my "Twinkie" :D

wierdscience
07-26-2008, 10:28 PM
Ok..so that 50cc Honda that did 23,000 rpm...I'm assuming it'd be a 4 cycle engine??? If it was..then how in the heck did they get the valves to work that fast? You'd have a hard time doing that with traditional type valve train..no?
Russ

Enter the Desmo-

http://www.bluming.com/projects/desmo.htm

Been around awhile-

http://en.wikipedia.org/wiki/Desmodromic_valve

How about TOHC?

http://www.motoczysz.com/main.php?area=home

http://en.wikipedia.org/wiki/MotoCzysz

Peter S
07-26-2008, 11:21 PM
Like Bob, I would guess it was Peugeot, and it is not at all surprising because they were the first company to use DOHC in their history-creating racing cars in 1911. According to one of my favourite engine books - "The Classic Twin-Cam Engine" by Griffith Borgeson, the twin-cam, four valve 500-cc parallel twin appeared in 1914. There is a photo of one of these bikes at Brooklands.
Peugeot had been making bicycles since 1885, not to mention tricycles, quadricycles, steam-powered tricycles and by 1891, Daimler-engined quadricycles. Peugeot vehicles finished 2nd and 3rd in the worlds first formally organised motor race in 1894 (behind a steam-powered de Dion). In 1899 Peugeot started making motorcycles.
BTW, I happened to see one of those early (1884) De Dion steam quads about three years ago in a garage in England. It was wonderfully original and still in running order, apparently the oldest running motor vehicle in the world.

Having said all that...it is astonishing what turns up, maybe there has been another, older DOHC cam, 4 valve twin turn up....

torker
07-26-2008, 11:29 PM
Enter the Desmo-

http://www.bluming.com/projects/desmo.htm

Been around awhile-

http://en.wikipedia.org/wiki/Desmodromic_valve

How about TOHC?

http://www.motoczysz.com/main.php?area=home

http://en.wikipedia.org/wiki/MotoCzysz
Ah..ok.. I have about 25 of them old Hondas. was wondering how the ancient tech on those equalled 23,000 rpm. I get it now!
Russ

John Stevenson
07-27-2008, 05:07 AM
Yes it was Peugeot in 1913
500cc twin, DOHC, 4 valves per cylinder.

For about 5 or 6 years I followed up on a rumor that there was the remains of one in the Euipen area on the Belgium / German border.

Even had people looking and did about 6 trips over there but never found anything but the leads did come from unrelated sources.......perhaps.

Saw Jean Nougier's SOHC bike back in 1988 when we did a detour :D coming back from the Nurburgring races, some detour he lives / lived just outside Marseilles in the south of France.

Unfortunately he had no English and we had no French so it was a 3 hour discussion made up of pointed fingers, sketches and grunts but still a nice guy.

Here's a bit of potted history.

http://www.stevenson-engineers.co.uk/files/8valve%20DOHC.pdf

.

bob ward
07-27-2008, 05:57 AM
I have read, not sure where at the moment, and it sort of makes sense considering the times, that the first 4 valve engines were designed that way not so much as a means of increasing horsepower but more as a means of increasing engine reliability.

The theory was that if one valve train failed, the engine would keep running because you still had (hopefully) the other valve still operating.

motorworks
07-27-2008, 09:57 AM
Good one John
I will print it off (with ur ok!)
take care
eddie
ps Going for a run on my
Suzuki SV650S
Vee Twin water-cooled
4 valves per cylinder

Peter S
07-27-2008, 08:04 PM
Bob,

I guess that having four smaller valves was inherently more reliable than two large valves, however when you read the Peugeot story, it is plain that high performance was at the heart of their impressive engine. Their first DOHC engine had four v-inclined valves with pent-roof combustion chamber and central sparkplug. It also had a semi-desmodromic valve system. By 1913 the desmo sytem was dropped, the shaft and bevel drive to the cams was replaced by a train of gears, the engine was dry-sump and the aluminium crankcase was the barrel-type with counter balanced crankshaft and ball bearing mains.

By the way, one characteristic of Henry's design was to make the combustion chamber slightly bulged at the ends so the valves could overhang the bore slightly. This allowed larger valves and coulld also prevent a broken valve dropping in to the cylinder (unless it broke close to the valve head...).

Another stunning feature was that "both valves are open at the same time" - possibly the first time valve timing overlap was used.

These Peugeots also ran what was later considered maximum piston speed (4,000 ft/min), the fact that this was at 'only' 3,000 rpm was because of their long stroke. (Most people think now days that old engines were all long stroke, actually many of the earlier racing engines were over square, square or only slightly under square. Peugeot however was the king of the long stroke builders in their earlier attempts to push the rule boundaries).

There were many interesting racing engines built in these early years, for example in their first race in 1912, the Peugeots were up against many impressive rivals with four-valve heads, SOHC etc. etc.

drof34
07-27-2008, 11:33 PM
Many of you probably already know this but I will throw it out there anyway.

Which motorcycle had a rear wheel whose axle did NOT pass through the center of the wheel?

Jim W.

Peter S
07-28-2008, 08:03 AM
Jim,

Not sure if this is what you mean, but the sprung-hub design used by Triumph (and maybe others?) probably qualifies. I think the last time I saw one was on a chopped Thunderbird (1960's?), gathering dust in a shed. I guess it gives the nice rigid frame look with suspension, but I have read that it wasn't a great sucess....

gnm109
07-28-2008, 11:46 AM
Jim,

Not sure if this is what you mean, but the sprung-hub design used by Triumph (and maybe others?) probably qualifies. I think the last time I saw one was on a chopped Thunderbird (1960's?), gathering dust in a shed. I guess it gives the nice rigid frame look with suspension, but I have read that it wasn't a great sucess....


I don't know how successful they were but Triumph used the spring hub for some years in the late thirties when the bike first came out until the time they went to the swing arm.

Alsmot all of the Trunderbird models, like the one ridden by Marlon Brando in the Wild One, had spring hubs.

They were fairly stiff and that resulted in the sprung hub being the only form of rear suspension being approved for Class C motorcycle racing in the US when it came out. The rules specified no rear suspension and no brakes but I recall seeing them on bikes on flat tracks n the 1950's.

When there was no load on a sprung hub, the hub would be sitting up a couple of inches and the axle would be toward the bottom of its travel, not in the center, so perhaps that would be the answer to the question.
.

drof34
07-28-2008, 12:55 PM
That is exactly what I'm talking about. I used to own an old 650 Triumph with the sprung hub with a very temperamental Lucas magneto. I used to push it about as much as I rode it.

Jim W.

Peter S
07-30-2008, 06:22 AM
Here is a photo of a DOHC Peugeot from the "The Classic Twin-Cam Engine" by Griffith Borgeson

http://img.photobucket.com/albums/1003/PeterS/Peugeotdohcmotorcycle-red.jpg

And a Triumph sprung hub from "Bonnie" by J.R. Nelson

http://img.photobucket.com/albums/1003/PeterS/Triumphsprunghub-red.jpg

Remote needle
07-31-2008, 11:24 AM
Sir John

Hendee Mfg. Co. (Indian) had a prototype racer at I think about 1910-12
It may have been a little later. It war of course a 1000cc V-twin made for the
mighty board tracks of the era. They had four valves per cylinder and a
eksposed verical shaft up the rear cylinder driving bevel gears.Then a second
eksposed shaft across to the front cylinder, all looking very impressive/fearsome !
Appearently it was not a success as onely one was made.
Come to think of it, it may have been a SOHC - oh well, never mind.

Apart from that, your fin straightening advice turned out well and my
cammy Norton is now looking very much better, Thanks !

Regards
Arne

stuntrunt
07-31-2008, 01:35 PM
Many of you probably already know this but I will throw it out there anyway.

Which motorcycle had a rear wheel whose axle did NOT pass through the center of the wheel?

Jim W.

MV agusta

http://i126.photobucket.com/albums/p84/stuntrund/monomoto_front.jpg

Runt

drof34
07-31-2008, 10:25 PM
Pray tell Stuntrunt, what was your handle before you started riding that thing?:D :D

Jim W.

Evan
08-01-2008, 07:10 AM
I am pretty sure it isn't possible to actually ride that thing.

Charles Ping
08-01-2008, 12:07 PM
You may well be right but I think that we'd both like proof that you're wrong!

This however, is rideable

http://english.vietnamnet.vn/dataimages/original/images452351_monowheel.jpg

drof34
08-01-2008, 09:07 PM
Just think what a ride that would be if it locked up.:eek: :eek:

Jim W.

DICKEYBIRD
08-01-2008, 09:27 PM
What happens when the obligatory little ol' blue haired lady creeps out in front of you in her Buick Century and you have to nail the brake? Whoopeeeeeee!;)

Peter.
08-02-2008, 04:44 PM
Many of you probably already know this but I will throw it out there anyway.

Which motorcycle had a rear wheel whose axle did NOT pass through the center of the wheel?

Jim W.

Most modern sportsbikes. The spindles are hollow, so if you go to the exact centre of the wheel there is nothing there at all.

Peter S
08-04-2008, 06:46 AM
I came across another early DOHC engine, this one from 1911, or 1912. It was made by Paolo Kind & Cie, steam locomotive and ship engine builders of Turin. It is not strictly DOHC, in that this was a two-stroke scavenged (reversible) marine diesel, so both camshafts operate scavenge valves, the scavenge air is supplied under pressure by the stepped piston. The scavenge pump cylinder is a seperate cylinder attached under the power cylinder. The trunk-type power piston is extra long, and the scavenge piston takes the form of a flange, with piston rings, attached to the lower end of the power piston. This engine was a four cylinder, rated at 100 hp at 375 rpm.

This photo and info comes from the excellent and monumental "Diesel's Engine" by Lyle Cummins. It is one of many hundreds of diagrams and photos used to illustrate this book. I came across an even earlier DOHC engine in the same book - a 1909 Sulzer marine diesel (1907 in another book), also uniflow and reversible with twin cams working inclined scavenge valves similar to the engine above. Sulzer sold five such engines in four cylinder form, then dropped uniflow scavenging and adopted loop scavenging. Sulzer reverted to uniflow many years later in the 1970's, when the lengthening stroke of their marine diesels made uniflow scavenging a better method. However, they then used the valves for exhaust, not inlet.

http://img.photobucket.com/albums/1003/PeterS/PaoloKinddohc19122strokediesel-red.jpg

stuntrunt
08-04-2008, 03:32 PM
I am pretty sure it isn't possible to actually ride that thing.


Well...
http://i126.photobucket.com/albums/p84/stuntrund/17d.jpg
http://i126.photobucket.com/albums/p84/stuntrund/Phlog_Roadster.jpg
http://i126.photobucket.com/albums/p84/stuntrund/Phlog_Owen_monowheel.jpg
http://i126.photobucket.com/albums/p84/stuntrund/Phlog_Kerry_V8.jpg

Runt

stuntrunt
08-04-2008, 03:33 PM
Many of you probably already know this but I will throw it out there anyway.

Which motorcycle had a rear wheel whose axle did NOT pass through the center of the wheel?

Jim W.

Lookie here
http://www.burningart.com/meico/moto/sbarro/

Runt