KZ650 SR

ckahleer
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How is top speed determined

24 Apr 2020 19:28

Depending where you get your specs from, top speed for my 81 kz305 varies from 86mph to 97mph.
I think 86mph is more realistic.
I just got my bike running well enough today to give it a good work out. On level highway, no wind, and sitting in a standard riding position, I could hit 84mph at 7,800rpm. (speed confirmed by gps.)
I'm thinking the sites listing 97mph are calculating a top speed if the bike could hit red line in high gear.

1997 ZL600
94 KE100
82 KZ305
74 TC185

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650ed
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Re: How is top speed determined

24 Apr 2020 20:20

#824197

Maybe this guy could get the bike to go 97 mph. :laugh: Ed

1977 KZ650-C1 Original Owner - Stock (with additional invisible FIAMM horn)

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TexasKZ
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Re: KZ650 SR

25 Apr 2020 07:21

#824231

World's Fastest Indian. Great story, and a must-see movie for any motorcyclist.

Motorcycle magazines competed with each other to see who could get the most out of every motorcycle they evaluated. This sometimes led to some shenanigans. It was pretty common practice for them to hire the tiniest professional rider they could get, to wring every last mph and lose every .01 second they possibly could. Racing tires, very careful "tuning" and the like were often employed.
The Internet has greatly multiplied the number of inflated, unreliable performance numbers available to enthusiasts these days.

1982 KZ1000 LTD parts donor
1981 KZ1000 LTD awaiting resurrection
2000 ZRX1100 not ridden enough

www.kzrider.com/11-projects/620336-anoth...uild-thread?start=24

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martin_csr
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Re: KZ650 SR

25 Apr 2020 12:02 - 26 Apr 2020 04:25

#824250

The engine rpms & overall reduction ratio plus the size of the rear wheel can be used to calculate the speed.
Non-stock sprockets will change the listed reduction ratio & a different wheel size can change the calculations.

From EB a KZ305 tachometer has a 10000 rpm redline, so using that number & 24.5" rear wheel diameter, I calculated a max speed of 99.2 mph (theoretical). I came up with a speed of 77.5 mph @ 7800 rpms. And 89.4 mph @ 9000 rpms (same as gearing commander).

1981 KZ650 Competition Sports and Road

Last edit: 26 Apr 2020 04:25 by martin_csr.

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Street Fighter LTD
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Re: KZ650 SR

25 Apr 2020 14:16

#824255

TexasKZ wrote: World's Fastest Indian. Great story, and a must-see movie for any motorcyclist.

Motorcycle magazines competed with each other to see who could get the most out of every motorcycle they evaluated. This sometimes led to some shenanigans. It was pretty common practice for them to hire the tiniest professional rider they could get, to wring every last mph and lose every .01 second they possibly could. Racing tires, very careful "tuning" and the like were often employed.
The Internet has greatly multiplied the number of inflated, unreliable performance numbers available to enthusiasts these days.

PEE WEE Gleason was the most sought after rider to wring out test bikes.
Small, light guy, with quick reaction times and no fear of the machines
Dave

Original owner 78 1000 LTD
Mr Turbo Race Kit, MTC 1075 Turbo pistons by PitStop Performance , Falicon Ultra Lite Super Crank, APE everything. Les Holt @ PDM's Billet Goodies . Frame by Chuck Kurzawa @ Logghe Chassis . Deep sump 5qt oil pan. RIP Bill Hahn

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