vintage?

[schmanman]

this is a question, the answers will most deffinantly vary from person to person, but what do you consider vintage?

60's?
70's?
80's?
90"s (I hope not)

I think of anything from the 80's or older as a vintage bike. how about you guys?

just thought it was an interesting question, but feel free to delete this, mods.

 

[76GMC1500]

I believe the beggining of the modern dirtbike occured when rear wheel disk brakes became standard. By this point, monoshocks, power valves, water-cooling, and cartridge forks had already been introduced. The frame construction/geometry also stuck until the mid-90's when the perimeter frame became standard. I would say 86/87 were the first years of the modern dirtbike (also the same years of the production rule in motocross, coincidence?). 84 and 85 are kind of the fuzzy years and anything prior is vintage.

 

[schmanman]

would any kawsaki 2-stroke from 79'-below have a powervalve?

 

[76GMC1500]

When I think of a powervalve, I think of a something that changes something in the exhaust based on engine rpm to increase the useable power range of an engine. Kawasaki did have exhaust valves in the 70's as did many other manufacturers. Most were some sort of rotory valve that allowed the engine to operate with asymetrical port timing. Yamaha introduced the first powervalves in the early 80's.

 

[schmanman]

right.... :think:

 

[pryor]

Vintage 1974 and older right?

 

[2stroke]

AHRMA breaks them down into many categories, but in a broader sense they group all of those categories as either vintage or post vintage.

Generally, vintage is 74 and back with some exceptions.
Post Vintage is 75 to about 82,83 depending on brand and equipment. Its more a formula of suspension and components than a strict year cut off.


My 1972 F9 is a vintage 'sportsman' bike but you can run up to a '75 F9 because it falls under the "like design" clause, that is, 4 inches of rear travel or less and 7 inches or less in the front.


The first class that is considered as "post vintage"is the historic class which is described as the first generation of long travel machines. (The first Yamaha mono shock bikes, as well as the long travel lay down twin shock bikes.)


The most modern machines that AHRMA allows in MX are called Ultima and are defined as:
Ultima class machines can have water cooling and linkage type rear suspension, but cant have disc brakes or any power-valve built directly into the engine. (YVPS equipped Yamahas are allowed.)

 

[thorman75]

The vintage club I belong to here in Indiana decided to make things alot simplier.The classes are 1974 and older and 1975 to 1983. Thats it and besides age groups thats all. 1 race per month starting in April ending in October.No AMA, no AHMRA, total outlaw.
www.ivorme.com

 

[Britt Boyette]

would any kawsaki 2-stroke from 79'-below have a powervalve?

No, they did not have a power valve. They did have a reed valve though.

 

[SHSPVR]

When I think of a powervalve, I think of a something that changes something in the exhaust based on engine rpm to increase the useable power range of an engine. Kawasaki did have exhaust valves in the 70's as did many other manufacturers. Most were some sort of rotory valve that allowed the engine to operate with asymetrical port timing. Yamaha introduced the first powervalves in the early 80's.

Really it called rotary disc valve and it only for carb intake not exhaust.

 

[schmanman]

yep, my engine has one of those.

 

[Britt Boyette]

Some Kawasaki's and Can-Am's used rotory and yes, they were used for the intake charge only. The Kawasaki's usually had the carbs mounted on the left side of the engine which could be a problem on the race bikes if the cover was damaged in a soil sample. The F81M of 71 and the Green Streak G31M also had a filter mounted on the outside of that same cover and seemed to be easy to kick it inwards in the heat of battle.

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