Dirt Bike History 101

[motu]

Originally Posted by kittycactus

Thanks for the history motu! What time period are you writing about in this post? And as for the picture above - what is it? That was part of the problem I encountered going through some of the other threads here, the bikes were not always labeled. I wish I had much more time to spend online, but I don't.

The time period is the late sixties - the first Motocross bikes were the big British 4 strokes,then came the first 2 strokes from Europe,the Japanese entered in the early '70's.If you look at Joel Roberts career he did his early Championships on CZ's,he later moved to Suzuki.So the first 2 strokes to knock the big 4 strokes from the top were from Europe,not Japan.

The bike in my picture is a Rickman Metisse,a hand built British motocrosser - they made frames from Reynolds 531 tubing,Ceriani forks and whatever engine the customer wanted....most often a Triumph twin.That bike is a 1964 with a unit 500cc Triumph engine.I got it in 1974 and it had been uncompetitive for at least 5 years.I made it into a road bike,or really a gravel road bike as that is what I rode on then.

[Valleyrider]

Well, with the emphasis on 4 strokes and British Iron, here's my 1972 BSA B50 in a Cheney frame at the Dinosaur race at Perris California held May 1, 1977. The bike was originally built for and owned by Paul Smart.

[Valleyrider]

Another classic, Joel Roberts RN71 in my living room.

[Trailing Jack]

Originally Posted by Valleyrider

Another classic, Joel Roberts RN71 in my living room.

Wow! How did you acquire that bike?
Do you still have it?

[Valleyrider]

Originally Posted by Trailing Jack

Wow! How did you acquire that bike?
Do you still have it?

I worked at Suzuki Motor Corp. at the time. I had been to an advertising shoot for Champion Spark Plugs. It got done late and instead of leaving the "Priceless" bike in the back of the company van overnight, I put it in the house. Do you blame me?? We had several "Factory" bikes stolen from the company parking lot around this time.

[RocketJ]

These are my opinions, and memories of the time.
While definitley running paralell, the two are not exactly the same. both from the consumer standpoint and that of the manufacturer.
The Japanese did popularize dirt bikes and 2 strokes in general by making a affordable, reliable and useable product available to the general public.
Edison Dye brought the Europeans and MX as we came to know it to the huge U.S. market.
In the late 60's and into the 70's, what the europeans raced, you could buy. When the Aisians got involved, the term works bike got popular, mainly because their race bikes only had a passing resemblence to what you or I could buy.
Up until 73/74 in the U.S. we could spend big bucks and buy a CZ, Husky, Maico, Bultaco or the like and go racing.The other option was to go cheap, buy Asian then crash and get beat a lot or spend big bucks trying to make them as good as the euros.
The CRs changed all that. Honda did not build them to a price point, as had been the case. They built them to flood the market and win local races at any cost. They figured, correctly, that they could make more from the PR than individual sales. Everybody else had to follow suit or lose market share and glory.
The next big event happend in mid 74. Yamaha had recently come out with the mono shock. Ake Johnsson a Maico rider was frustrated with it's success (losing). The story goes, he asked an old factory guy what could be done. This guy said it was simple, move the shocks foward and get more travel, duh. They did that, so said in a hotel parking lot, at night, mid series, he won the next day and the rest as they say is history. The next week, all the factory guys had some version. The next month all the local guys did it also.

[Trailing Jack]

Originally Posted by Valleyrider

I worked at Suzuki Motor Corp. at the time. I had been to an advertising shoot for Champion Spark Plugs. It got done late and instead of leaving the "Priceless" bike in the back of the company van overnight, I put it in the house. Do you blame me?? We had several "Factory" bikes stolen from the company parking lot around this time.

[dan-c]

Originally Posted by RocketJ

These are my opinions, and memories of the time.
While definitly running paralell, the two are not exactly the same. both from the consumer standpoint and that of the manufacturer.
The Japanese did popularize dirt bikes and 2 strokes in general by making a affordable, reliable and useable product available to the general public.
edison Dye brought the Europeans and MX as we came to know it to the huge U.S. market.
In the late 60's and into the 70's, what the europeans raced, you could buy. When the Aisians got involved, the term works bike got popular, mainly because their race bikes only had a passing resemblence to what you or I could buy.
Up until 73/74 in the U.S. we could spend big bucks and buy a CZ, Husky, Maico, Bultaco or the like and go racing.The other option was to go cheap, buy Asian then crash and get beat alot or spend big bucks trying to make as good as the euros.
The CRs changed all that. Honda did not build them to a price point, as had been the case. They built them to flood the market and win local races at any cost. They figured, correctly, that they could make more from the PR than individual sales. Everybody else had to follow suit or lose market share and glory.
The next big event happend in mid 74. Yamaha had recently come out with the mono shock. Ake Johnsson a Maico rider was frustrated with it's sucess. The story goes, he asked an old factory guy what could be done. This guy said it was simple, move the shocks foward and get more travel, duh. They did that, so said in a hotel parking lot, mid series, he won the next day and the rest as they is history. The next week, all the factory guys had some version. The next month all the local guys did it also.

As a side note to moving the shocks forward for extra travel, Harley had been doing that for years, prolly not for the same reason though.


And some of the early mono shocks had Maico forks grafted on. Maico was putting ~ 7.5 inches of travel on the front since the late 60's.

[RocketJ]

Originally Posted by dan-c

As a side note to moving the shocks forward for extra travel, Harley had been doing that for years, prolly not for the same reason though.

Very true. That was actually how the original story went ( the Duh part). That is where the idea came from.

[nachtflug]

Originally Posted by kittycactus

It's interesting that engine displacement seems to be all over the place with the older bikes. Any particular reason for that or was it just a period of trial and error and growth? How did they lump bikes together for races?

I think it might be a little misleading. things were either 125-250, or open class, sometimes referred to as the 500 class.

but anything bigger than a 250 went there and they all knew the deal. there were few real 500's except the thumpers, BSA's etc, but then again it all depends when you were talking about. For me, starting point of reference 1970, the 500 class was an endless procession of 350's, 360's, 370's 380's 390's, 400's galore, 420's, 440's, 450's, 480's, 490's the legendary 501 Maico, and then the big boys on the BSA's and even Triumphs.

You run what you brought in the 500 class. too bad they killed it.

and we're talking more MX here. In scrambles there would be also a 200 class chock full of Bultaco's with a few stragglers thrown in on Pentons or hotted up Jap.

and of course lets not forget the 100 class chock full of Hodaka's and more hotted up Jap with the Kawasaki Centurion as a bonafide race bike circa 1970. the 100 class made the 125's sound like thumpers in comparision.

then of course in enduro's there would be a 175 class....

and of course todays 250 class where you can run a 450.

and the 125 class where you can run a 250

but they've finally changed it to legitamize the cheaters. to "lights"

[nachtflug]

Originally Posted by nachtflug

Iendless procession of 350's, 360's, 370's 380's 390's, 400's galore, 420's, 440's, 450's, 480's, 490's the legendary 501 Maico,

as I sit here with a 465 Yamaha 100 feet away from me albeit outdoors in a garage.

I knew I left somebody out.

hey what about the 430 Husky's! The 495 KTM's!!

[RocketJ]

In the early days one could actually go faster, longer on a 250 even though they where pretty much the same otherwise. The 360 etc where much more rideable than the 501s.
I used to "cheat" and win riding a 250 CZ in the open class. Once in a while, I would swap the yellow plastic tank for a red one and ride both classes.

[Easy-Z]

Thanks for starting this Kittycactus. I'll be watching this one closely to see if I can learn a thing or two.

Off topic: I lived the first 25 years of my life in Michigan and never knew there was actually a town called Wolverine...... Huh!

Now my n00b question if you don't mind. Everyone always talks about how much better a monoshock is than having two. Because I've never asked, I can't figure out why that is. I'm sure it's obvious but can someone please enlighten me?

[RocketJ]

Originally Posted by Easy-Z

Now my n00b question if you don't mind. Everyone always talks about how much better a monoshock is than having two. Because I've never asked, I can't figure out why that is. I'm sure it's obvious but can someone please enlighten me?

A couple of reasons.
The main one has a lot to do with the state of damper (shock) art at the time. One of the enemies is heat, a smaller shock heats up faster and becomes ineffective. The shorter stroke of the mono allows the valving to respond quicker and by being larger it could have more complicated valving. it could also have a more progressive action due to the changing angles of the swingarm mount. volumes have been written on this stuff.

[motu]

Moving to monoshock was night and day - with 300mm (1 foot) travel front and rear you could ride in 4th or 5th gear on open trails,the bike just floating under you and kicking around a bit.NO WAY could you ride that fast on a twin shock bike and live.But the last of the top line bikes,like Husky,had very good twin shock suspension with 300mm travel and superior handling of course.

The other big step after monoshock was power valves on 2 strokes.This transformed totaly violent instant snapping powerband bikes like the Husky into bikes with power from idle until your vision got blury.It was very hard to ride those powerband bikes....or at least for mere mortals like me.You had to get the bike lined up and pointing somewhere safe before you opened it up.It was like walking in front of someone swinging a length of 4x2 behind you....you knew it was going to connect sometime,'twas scary.