The top speed of a K1...

Let's talk about the road burnin' potential of an '83 KZ750 LTD K1. That's right, that odd Twin with the belt drive.

I just bought one of these suckers a couple of days ago for a hard bargain, and I'm currently in the "research" stage of restoration. I've compiled a good amount of info on it, like HP, torque, and the like, but nowhere has a mention of top speed.

Initially I was surprised at the speedometer max of 85 mph, but I later found out this was due to the mid-80's government/manufacturer speedo deal. Interesting piece of history, but it makes for a misleading impression of a bike :pinch:
So it's no question the bike can pull faster than 85, but how much so?

Anyone want to take a guess?

Fastest I ever had my chain-drive twin up to was about an indicated 95, doubt there is much to be had above that. The twins aren't speed machines, more just torquey cruisers. Claimed top speed was 102.5

It will for sure go faster than 85, so be careful. Those speedometers were supposed to make cars and bikes safer (twisted logic) by not tempting riders to go above 85. Instead, they made bikes less safe. Example: My friend and I were riding back from superbike motorcycle races; I on my KZ650-C1 he on his KZ750 (4-cyl. I think a GpZ). On a very long stretch of smooth, traffic-free highway we get a little feisty and open up the bikes. I'm tucked in and running at an indicated 120 just at redline in 5th; he is riding in the lane next to me and pulls ahead of me; then slows; then pulls ahead then slows several times. 10 minutes (20 miles) later we pull off the highway for a burger (my heart is thumping!). He asks "why were you going so slow and wouldn't speed up?" I say "are you f'ing serious? I was flat out at 120 and didn't want to risk going beyond redline at that speed in case the engine blew up!" He says "120? Holy shyt! I thought we were going 85!" In fact, he had to be going at least 125 when he would pull away from me. I don't believe thinking you're going 85 when in fact you're going more than 120 is a safety feature. Ed

with 55 hp claimed, about 40 hp at the rear wheel, top speed would be about 100-105 mph. Quite academic data as they would vibrate quite a bit at those speeds though.

some people are racing them here in italy,

the twins are not really competitive with a race prepped KZ750 four but they can be quite fast if tuned.

Drool.

I like the simplicity and handling of twins, but wondered it the 750 was worthy of a weekend racing bike. Your image, is showing me that yes it is possible, and some are doing a great job of it.
Keep it up!
dc

Hatchet wrote: Let's talk about the road burnin' potential of an '83 KZ750 LTD K1. That's right, that odd Twin with the belt drive.

I just bought one of these suckers a couple of days ago for a hard bargain, and I'm currently in the "research" stage of restoration. I've compiled a good amount of info on it, like HP, torque, and the like, but nowhere has a mention of top speed.

Initially I was surprised at the speedometer max of 85 mph, but I later found out this was due to the mid-80's government/manufacturer speedo deal. Interesting piece of history, but it makes for a misleading impression of a bike :pinch:
So it's no question the bike can pull faster than 85, but how much so?

Anyone want to take a guess?

To calculate it, you'd need the frontal area(including you on it, I guess), coefficient of drag (I dunno where you'd get that). But looking around, these twins make what, about 40hp? So you could get close to 100mph. You might need to lie on the tank and have a stiff tailwind too.

But like you said, thats just my guess!

If you're a normal sized male sitting upright behind them tall bars, expect about 90 mph honest top speed. If you want to look really daft and lay down with your arms above your head, you may see the ton on a good day. And people would larf at you

oh, how i love it when the original poster doesnt even care to check replies to his topic....

sorta, why bother ?

no worries though cause it took me about a week to get bored enough to check the top speed of this thread myself.......

i would think at sea level and with a decent twin ....slight downhill long straight...wind at your back.....well waxed helmet...one hand tucked in...laying on tank.....100 easy

That's funny.
I couldn't begin to guess, never had one. But I do have a 67 W2SS 650 twin Kawasaki, specs show top speed of 110 mph. I doubt it myself but that's what they claim.

Les

My buddy road races one and he took the motor from 48HP to 78 and later 82 RWHP. He is an amazing rider and is hard to beet especially on the short tracks. He can easily stay with the liter KZ's. There a picture (poor one at that) on my website www.teamkz.ca 'bikes I built' at the bottom.
P.S his bike could easily do 125mph

www.amazon.com/gp/bit/apps/web/SERP/redi...hbase%2Fairfri2.html :laugh: :laugh: :laugh: :laugh: :laugh: