Topic: breaking 100 mph

[jaguar]

I see zero reason that a well maintained CB750 would be "unsafe" at 100mph today.

[Dunk]

100mph isnt that fast guys.....

... On public roads, it’s often 170% of the speed limit and a danger to everyone else around you. Who among us deserves the right to endanger others so wantonly? Want to risk your life, fine by me. Risk mine, and I’ll put you in the ditch personally as a Public Service.

Says the guy in arbitrarily low 55 MPH land (Virginia) and some of the most oppressive laws regarding driving and speed. Exceeding an arbitrary number on a sign does not endanger anyone. Failure to maintain proper lane discipline  (drive right, pass left), failure to signal, failure to check blind spots, and any number of other offenses do regularly risk lives and actually harm people... Yet your focused on something that has nothing to do with safety? Read up on 85th percentile speed limits. Here was the first result in a search, interestingly enough from Texas, a state that apparently has some 85 MPH speed limits. http://onlinemanuals.txdot.gov/txdotmanuals/szn/determining_the_85th_percentile_speed.htm

[flatlander]

don't make this your goal. chances are you will focus too much on reaching some top speed instead of being aware and doing what's sensible.
do whatever is right for the road, its conditions, traffic, the bike, your own judgement, etc. then when the time is right you will just hit that 100. if that's not today or tomorrow but some other day - who cares?

[MRieck]

Speed limit on 87 (northway around here) is 65mph.

People REGULARLY cruise at 75-80mph.
A quick blast to 100mph is not hard.
Heck you could do it have have zero people on the road even know you did it....

I shift into 6th at 80mph on my busa.....and that's with 3 extra teeth on the rear.

[BobbyR]

You need to make sure you have very new tires and your swingarm has no play. Animals, gravel and a crappy patch job on the roadway as said can get you dead. I know this is something you need to do, we all have to at least once. If all things check out good you can do a burst to 100 and then say you did it. From 75 to 100 is a quick trip on a good running 750.

[BobbyR]

Speed limit on 87 (northway around here) is 65mph.

People REGULARLY cruise at 75-80mph.
A quick blast to 100mph is not hard.
Heck you could do it have have zero people on the road even know you did it....

I shift into 6th at 80mph on my busa.....and that's with 3 extra teeth on the rear.

Of course, one of the best wrenches and engine builders in the country can do that. We mere mortals are at a disadvantage.   

[ekpent]

 I was winding up my Bandit 1200 a little when Sean and I left an intersection this summer and looked down and was already well over 100 mph and if remember correctly was still in 3rd. Didn't feel that fast per say but the bike is built for it.

[RandomOrbit]

Just a thought I've wondered about for about as long as I've owned my bike, but I don't have the math for it. I figure these old mechanical speedos are not that accurate anyway, but I wonder how much difference running 100/90-19 makes over running the stock 3.25-19 in terms of speedometer readings.

[pjlogue]

If you do decide to do a fast run I would make damn sure your wheel bearings are either new or at least visually checked and repacked, steering head bearings replaced if not new, wheels trued and balanced and swing arm has been overhauled and checked to be sure there is no slop.  If you break into an oscillation at high speed it can happen so fast you won't have time to react. 

-P.

[jlh3rd]

Few years ago, some 20 something guy was riding his crotch rocket down the interstate,estimated over 110, 120. They found the bike approximately 100 yds. up ahead of his body...they figured he was crouching down hugging his tank and then sat up real quick to slow down, so he blew himself off the bike....
Just sayin...
I did get my 71 450 up to 95 back in the day....one time....

That’s the completely wrong assumption as to why he was no longer on the bike. 

Evinrude - DON’T ride 100mph on public roads. Simple as that. Modern or vintage bike, doesn’t matter. Roads are not designed with the horizontal or vertical sight distance to safely pilot a bike (or car) at those speeds. I get the goal, but instead of public roads, do track days, or take Advanced Rider courses and really learn how to ride a bike. Even training courses held on tracks are heaps more fun and far better learning environments than public roads.

A fall at 20mph will kill you. At a minimum, you’ll be facing ortho surgeries, recovery times, and busted bikes. At 100mph, it becomes a guaranteed terminal event. Is it really that important to say you broke the Ton on a bike to risk your life, your family’s well-being and financial security? There’s nothing worth that risk.

I didn’t assume anything at all...old buddy....it was in the police report as reported in the news.....old buddy....
If you reread my post, I said “ they”....not “I”....
I’m not the one making an assumption......old buddy....🙄
You can roll you’re eyes at someone else......ok.?

[Stev-o]

There's nothing inherently unsafe about 100 MPH.

 Should you on public roads? No FCUKING way!

Wow...what a Debbie Downer!   Let the guy do his bucket list item "The Ton" and be done with it..

[robvangulik]

Speed limit on 87 (northway around here) is 65mph.

People REGULARLY cruise at 75-80mph.
A quick blast to 100mph is not hard.
Heck you could do it have have zero people on the road even know you did it....

I shift into 6th at 80mph on my busa.....and that's with 3 extra teeth on the rear.

I suppose that's at half throttle, as my 30 year old CBR1000F does 150 mph/240kph in 5th before shifting to top gear?

[my name is nobody]

Something else to consider too, is the ability to stop in a panic situation. Most of the sohc 4 bikes that have drum type rear brakes leave a lot to be desired during a panic situation. They lock up easily. Don't ask how I know this...







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[Dunk]

There's nothing inherently unsafe about 100 MPH. Keep in mind speed limits in the USA are arbitrarily set low and not based on safety, road design, visibility, etc. In most states speed limits are significantly lower than they were 50-60 years ago, think of the vehicle and suspension design at that point in time. Heck, think of the tires.

I'm sorry, but this is simply not true. I speak from professional experience in road design to know this. Roads are designed for their travel speed based upon volume of projected traffic.

Then you should be very aware and knowledgeable regarding the 85th percentile speed, as well as how most roads are posted well below this most likely for surprise road tax collection purposes.

Its whether traffic on that road can tolerate a vehicle traveling at 150% of their speed. This is incredibly dangerous to all on the road.

Lane discipline, signaling intentions, checking blind spots... These are real things that affect safety. You harp on speed, which is fairly irrelevant and in fact many or even most speed limits are posted well below the 85th percentile, arguably the safest speed limit. Some more reading here: http://www.sehinc.com/news/truth-about-speed-limits-explained-engineer

Each is bestowed with Free Will. Choose your path. Expect not a tear or frown from me if you wrap your ass around a tree or parked car, or someone pulling out in front of you and kill yourself. Good riddance to you I say. If your own damn self-absorbed thrill-seeking butt chooses this, you deserve a dirt nap. I will simply add to your post in the Memorial Board; Got what he deserved.

I guess I'll try to avoid Virginia, wouldn't want you to get angry and murder me if I happen to be traveling faster than the posted limit, at the 85th percentile speed which is statistically the safest.

[pjlogue]

In pushing 45+ years of riding I don't ever recall seeing a rider blow between 2 lanes of heavy traffic, blow past me like I'm standing still, pop wheelies, weave in and out of traffic while doing well above the traffic flow...not one with any grey hair poking out from under the helmet.     The older riders haven't earned a Darwin award.

I have had 2 major mishaps over the years, both times I have been very lucky.  One time a buddy and I were riding at night doing 55 behind a truck.  Before I knew it a concrete block appeared from under the truck (truck had enough clearance to clear it) and I hit it square on.  Launched me 3' in the air and I came down at an angle but somehow I managed to remain on the bike and bring it to a stop.  Front rim was bent bad.  Another time I was cruising with my faience on the back and the front tire went flat within 100'.  Bike started going rack to rack but I managed to keep it upright.  Turned out I hit a spring from a close pin which tore a big hole in the inner tube.  Lesson learned was; even when not screwing around things can happen in an instant.  The cement block was my fault because I didn't leave enough distance between me and the truck.  It was adequate if the truck stomped on his brakes but not enough distance for something in the road.  2nd was you never know what's in the road.

-P.

[TwoTired]

...my confidence on the bike has become very solid. 

Just beware that confidence and complacency, have discernible distinctions.

i ride with the thought that other drivers are looking to kill me

That is a laudable practice for survival.  Served me well for 50+ years, even during my "invincible" period where I am fortunate enough to reflect upon.

Cheers,

P.S. Ever notice that racers run at high speeds on tracks that have been well characterized for traction conditions and hazards?  ...and don't have two way traffic, and hundreds of entry/exit points?

How many public streets have you characterized in the same way? ... on the day of your speed attempt?  Ever seen a leaking gravel truck on public highways?  Or a vehicle leaking lubricants?

[MRieck]

Speed limit on 87 (northway around here) is 65mph.

People REGULARLY cruise at 75-80mph.
A quick blast to 100mph is not hard.
Heck you could do it have have zero people on the road even know you did it....

I shift into 6th at 80mph on my busa.....and that's with 3 extra teeth on the rear.

I suppose that's at half throttle, as my 30 year old CBR1000F does 150 mph/240kph in 5th before shifting to top gear?

Not even.....it's idling. That bike has so much gearing I hardly use 6th. It was made ( the 1999/2000 models) to knock on 200mph stock.

[CBGhia]

Speed limit on 87 (northway around here) is 65mph.

People REGULARLY cruise at 75-80mph.
A quick blast to 100mph is not hard.
Heck you could do it have have zero people on the road even know you did it....

Yeah, I used to "ton-up" every morning on my way to work.  Hit a good stretch with no traffic at 6AM.  There isn't that much of a difference from the 80 that we are already going on the highway.

[ofreen]

Each is bestowed with Free Will. Choose your path. Expect not a tear or frown from me if you wrap your ass around a tree or parked car, or someone pulling out in front of you and kill yourself. Good riddance to you I say. If your own damn self-absorbed thrill-seeking butt chooses this, you deserve a dirt nap. I will simply add to your post in the Memorial Board; Got what he deserved.

Whew! I’ve heard this sentiment expressed by those who oppose motorcycle riding in general. Anybody who chooses to ride one of those deathtraps deserves what happens to them, to include dismemberment or death. You won’t see me shed a tear, they got what’s coming to them, blah blah blah. I don’t understand that way of thinking, but it sure is common.

I won’t add to the handwringing other than to say that while a 750 might have a 100 MPH engine (maybe), it doesn’t have 100 MPH brakes. If you are going to do it, pick your spot and time well.

[jaguar]

Really do not understand the fear from some of you guys.
We can agree that doing 100mph in traffic during rush hour while splitting lanes is a bad idea.
Also going fast on a poorly maintained anything is a bad idea.
Tires are important.
Knowing how long it will take to stop means something.

But the idea that a CB750 is not capable of being pushed that fast is hilarious.
These were and are performance bikes!

All my CB750s have been north of "the ton" at some point.
Did over 100 on my Norton.  Knew that because I was passing a Honda Civic with a large digital dash.
Found out when I got home I was leaking a little more oil then normal.....

My ZX10R would do 100 in 1st gear! 
My chevy is limited to 98.
Now that it is lowered I should remove the limiter....lol

[jlh3rd]

I didn’t assume anything at all...old buddy....it was in the police report as reported in the news.....old buddy....
If you reread my post, I said “ they”....not “I”....
I’m not the one making an assumption......old buddy....🙄
You can roll you’re eyes at someone else......ok.?

I wasn’t rolling my eyes at you, Buddy. I was rolling at their assumption. Don’t get your skirt in a twist, Buddy.

Now you can add liar to your repertoire.....

[BomberMann650]

Oh come on guise, talkin like you ain’t a bunch of ton up boys already.

Having an fjr1300 took all the excitement out of doin the ton.
Fairing, windshiled, modern tires and suspension.  Crack the whip in 4th gear from 75 and it just takes you there.  Still has rpm and a gear to go.

Now the cb550. 
That bike will remind you that there is a living thing underneath you. 
Trying to leverage all its might against the weight of the world. 
Desperate to dig its claws into the pavement.
A snarl between shifts and a howl as redline appears.
Rider and machine embrace.
A blade cutting through the sky.
85 - shift - 5th gear time to fly.
Elbows down, knees in, throttle wide open, eye on the horizon.
90, 95, 96, 97, will it get there?
A bump in the road, a shake in the bars.
Stay calm, keep focused, hold the throttle open.
98, 99, 100 they’ve done it!

Now back to the cafe to see if the song is still playing.

[PeWe]

100 mph + get a 1000 cc sport bike ...been there done that......these vintage bikes are not made safe for that speed ....tires/spoke wheels agh

My bike was ridden 100 mph and more very often back in the days. Touring thru Germany, Italy or France was equal to 100mph and more most of the time.  It happened that I had to keep 180-190 kph during a long period, the fuel vanished really quick!

I remember when the speedo showed 210kph with cases, fully loaded with 2 persons and luggage a little bit downhill and a looong nice curve from Austria to Italy, alps around, not letting a Jaguar XJS to pass me. The frame had some flex then  when leaning and I started to think about the nuts holding front axle, did I really tighten them enough at last repair?

Photo below on one of those trips 1985. The alps behind in northern Italy close to Austrian border. As I wrote earlier, steering damper helps. I noticed that 4-1 give better handling, easier front wobble when switching from 4-1 to 4-4 that new tires solved.

The bike has much tougher acceleration now, cruising in 100 kph on 5:th gear, just twist the throttle and suddenly I'll get a corner thrown in my face, 180-190 kph is reached really quick. I have dual front brakes that almost match Mikes Billet block and 10005cc which made a huge difference torque wise compared with 836. 2 old friends were surprised last summer since they have to twist a lot to keep up with my CB750 K6 on curvy country roads when I accelerated from 70 up to 180-190 kph (110-120 mph)
Aprilia Tuono 4 cyl model 2017 which is a lot faster and Honda CBR1100XX Super blackbird -1996 with 133 rwhp left but no fairing making speeds over 210-220kph very unpleasant for my friend.

Std rear tire dim positive too. Changed from 120/90-18 to 4.0-18.

Bike (avatar)  will get a Hindle 4-2-1 mounted this winter so I'll visit the other side of 200 kph more frequent next season! 

I'll might test the megacycle 125-75 125-20 cam again. Now with correctly jetted carbs. That cam did not respect the red line at all with 836, quickly to the other green area around 10.000 rpm.

So, a Honda CB750 can handle speeds around the 200 kph (125mph) limit
Very important to keep the eyes open on all other people on the roads and be prepared for cars crossing the road and not seeing you. Avoid accidents by riding, not braking which is not the best part of the CB750

Shocks back in the 80's was Marzoochi AG Strada, needle bearings in swing arm, tapered roller bearings front. Same now except for IKON shocks, progressive springs in fork and better steering damper bracket on frame. This match the +30 kg extra I have got

[flatlander]

Now the cb550. 
That bike will remind you that there is a living thing underneath you. 
Trying to leverage all its might against the weight of the world. 
Desperate to dig its claws into the pavement.
A snarl between shifts and a howl as redline appears.
Rider and machine embrace.
A blade cutting through the sky.
85 - shift - 5th gear time to fly.
Elbows down, knees in, throttle wide open, eye on the horizon.
90, 95, 96, 97, will it get there?
A bump in the road, a shake in the bars.
Stay calm, keep focused, hold the throttle open.
98, 99, 100 they’ve done it!

Now back to the cafe to see if the song is still playing.

LOL cowman, this almost has lyrical quality!

[Lostboy Steve]

I did what my speedo said was 130mph on my buell once.... ONCE. The reason? I wanted to see if the death wobble would go away after it started at 80. Results: it doesn’t.

My 550 on the other hand, even on the turnpike, isn’t comfortable over 80. It’ll do it, but it just feels like you’re on the edge of the limitations of the bike. If that makes sense.


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