Well how about it's one of the first American muscle bikes? (non limey)

 

Heck, I had a 350 Yamommaha that could beat a 900 sportie in the quarter mile. He was gaining on me near the end but my lead in the first eighth was substantial. Then I moved on to panheads which of course is less quick still but where's the dignity in hurrying?

 

not the 'original', but the vmax is pure muscle

 

I'll let you know when HD builds anything I'd consider a muscle bike. stock Sportsters just don't have the muscle, the V-rods have the power, but the liquid-cooled porsche motor is too small & too smooth. The Vr-1000 was a sportbike. The xl1000cr was a Sportster with a brittish accent. The sportcycle was a moped.

Now take a evo V-twin and put a 120" stroker kit on it..... Thats a custom muscle bike to be proud of.

 

I guess it depends on the historical context. The Sportster was THE muscle bike in the 60's. I'm sure the first twin produced in the teens was a muscle bike to those riding singles. You can't compare the power of today's bikes with those from 40 years ago. Apples & oranges.

 

Think you need to go back further. Try Crocker. Back in the Day, they were the fastest on two wheels of the production bikes.

 

who you guys kiddin,, and you will all agree,, but backthen,,
our starting years,,, the little Rupp mini bikes was the true muscle bikes
remember how your bicept hurt pulling on the chord

 

This is how I look at it…take a 70’s GTO; definitely didn’t have the top speed of a Ferrari or a Jaguar of the same year at top speed, but neither of them are defined as a muscle car either. Low end torque and quarter mile speeds always defined a muscle car to me. My 70 442 with a 455 was working hard to run at 100, but off the line, it was hard to beat.

You can’t compare the numbers produced back then with number produced today. At the time the first Sportster came to be, there were no bikes producing 140hp and the Sporty was real competition. Don’t know about being the first muscle bike…it was definitely a muscle bike.

 

When I weighed 140lbs,my '73 Z1 with Kerker 4 into 1 and rejetted carbs was a haul *** bike.I could beat a H-2 or H1 two out of three 1/4 mile runs.

 

My 1975 z-1 sings at 7000,my new bike will be pure power at 2000