Your top speed

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VT1000r
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Re: Your top speed

Post by VT1000r »

8541Hawk wrote: Thu Jan 24, 2019 11:06 pm Well not to ruffle any feathers but.....In it stock condition my bike would run up to around 9700RPM before saying she was done.
After a set of slip-ons,some of the emission stuff fell off :shh: and some carb tuning my bike had no real issues pulling to the rev limiter(10.3K) when I still had one.

Also one would also need to know if the bike in question was a first gen VTR or one of the later ones with the clock. I say this because the early bikes made 5 more BHP which can really help on the top end.
Yes you can do the research but the early bikes were dyno'ed at 105hp while the later models tested at 100hp

Now for true top speed, you can't trust the speedo for a couple of reasons.....and at the rev limiter it is buried past 180mph.
Now all speedos read slightly fast but reason why the error gets bigger as speed increases is a phenomenon called "tire slip"

This is also why if you go to a site like "Gearing Commander" the math says the VTR should have a top speed of 183.4 with stock gearing at 10.3K RPM.
Yet it is well published that a VTR tops out at around 160mph at the rev limiter. That almost 13% difference is due to tire slip.

What tire slip actually all means is that in order to create the traction needed to propel the bike forward the rear tire must produce friction with the road.
It does this by spinning slightly faster than the bike is actually moving. This is why the center of the rear tire wears at a much faster rate than the center of the front.
Also the faster you go, the more traction is required to drive the bike forward, so the tire slips more.

So IMHO the top speed of these bikes is right at 160MPH. Some of the race bikes might have a touch more, as I have seen rev limits to 10.7K but that might add 5 MPH or so.
The main advantage of the built engines is not more top end, they just get to the same top end much quicker.
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VT1000r
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Location: tennesee

Re: Your top speed

Post by VT1000r »

VT1000r wrote: Fri Jan 25, 2019 7:07 am
8541Hawk wrote: Thu Jan 24, 2019 11:06 pm Well not to ruffle any feathers but.....In it stock condition my bike would run up to around 9700RPM before saying she was done.
After a set of slip-ons,some of the emission stuff fell off :shh: and some carb tuning my bike had no real issues pulling to the rev limiter(10.3K) when I still had one.

Also one would also need to know if the bike in question was a first gen VTR or one of the later ones with the clock. I say this because the early bikes made 5 more BHP which can really help on the top end.
Yes you can do the research but the early bikes were dyno'ed at 105hp while the later models tested at 100hp

Now for true top speed, you can't trust the speedo for a couple of reasons.....and at the rev limiter it is buried past 180mph.
Now all speedos read slightly fast but reason why the error gets bigger as speed increases is a phenomenon called "tire slip"

This is also why if you go to a site like "Gearing Commander" the math says the VTR should have a top speed of 183.4 with stock gearing at 10.3K RPM.
Yet it is well published that a VTR tops out at around 160mph at the rev limiter. That almost 13% difference is due to tire slip.

What tire slip actually all means is that in order to create the traction needed to propel the bike forward the rear tire must produce friction with the road.
It does this by spinning slightly faster than the bike is actually moving. This is why the center of the rear tire wears at a much faster rate than the center of the front.
Also the faster you go, the more traction is required to drive the bike forward, so the tire slips more.

So IMHO the top speed of these bikes is right at 160MPH. Some of the race bikes might have a touch more, as I have seen rev limits to 10.7K but that might add 5 MPH or so.
The main advantage of the built engines is not more top end, they just get to the same top end much quicker.
Wow I always learn something new reading your posts there very informative, also was the 105hp at the rear wheel?
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8541Hawk
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Re: Your top speed

Post by 8541Hawk »

Yes that is rear wheel HP.The source I am using is the info that was published by CycleWorld & SportRider in their dyno tests :thumbup:
Loud pipes don't save lives, knowing how to ride your bike will save your life.
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lloydie
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Re: Your top speed

Post by lloydie »

Errr as fast as it would go pulling my fat ass down the track
tony.mon
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Re: Your top speed

Post by tony.mon »

Oh, sorry, I seem to have looked at fakebook instead of the forum.

I would have thought that a photo showing a sweep diagnostic speedo and rev counter at startup will always win the Aldi car park fastest bike pic competition.
182 mph at peak revs, but in neutral.

Please don't be offended.
Just my thoughts....
It's not falling off, it's an upgrade opportunity.
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VT1000r
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Location: tennesee

Re: Your top speed

Post by VT1000r »

tony.mon wrote: Sat Jan 26, 2019 12:17 am Oh, sorry, I seem to have looked at fakebook instead of the forum.

I would have thought that a photo showing a sweep diagnostic speedo and rev counter at startup will always win the Aldi car park fastest bike pic competition.
182 mph at peak revs, but in neutral.

Please don't be offended.
Just my thoughts....
If anyone gets offended by that they should really not be on the internet.
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fabiostar
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Location: sunny belfast

Re: Your top speed

Post by fabiostar »

VT1000r wrote: Sat Jan 26, 2019 6:40 am
tony.mon wrote: Sat Jan 26, 2019 12:17 am Oh, sorry, I seem to have looked at fakebook instead of the forum.

I would have thought that a photo showing a sweep diagnostic speedo and rev counter at startup will always win the Aldi car park fastest bike pic competition.
182 mph at peak revs, but in neutral.

Please don't be offended.
Just my thoughts....
If anyone gets offended by that they should really not be on the internet.
lmao have you seen how easy people are offended these days :lol: :lol:
the older i get,the faster i was :lol:
Swampy
Posts: 80
Joined: Fri Jan 04, 2019 1:03 am
Location: NZ

Re: Your top speed

Post by Swampy »

fabiostar wrote: Sat Jan 26, 2019 12:43 pm
VT1000r wrote: Sat Jan 26, 2019 6:40 am
tony.mon wrote: Sat Jan 26, 2019 12:17 am Oh, sorry, I seem to have looked at fakebook instead of the forum.

I would have thought that a photo showing a sweep diagnostic speedo and rev counter at startup will always win the Aldi car park fastest bike pic competition.
182 mph at peak revs, but in neutral.

Please don't be offended.
Just my thoughts....
If anyone gets offended by that they should really not be on the internet.
lmao have you seen how easy people are offended these days :lol: :lol:
I absolutely represent that!
Swampy
Posts: 80
Joined: Fri Jan 04, 2019 1:03 am
Location: NZ

Re: Your top speed

Post by Swampy »

Image

Flying quarter report. My first land speed trial as a participant

Setup- mirrors, pegscrapers, cameras gone, forks up to stock. Black blade changed to clear. 16/41 narrowed to 520, 42psi front and rear (max legal)

So much happening in a short time. 2 and a half k run up...should be heaps, yehnar. My gains, if any were by more agression in accelerating and tucking. Trying to fit my fat ass under the fairing had me sore by the end of the day.

I can do the math thanks. A long way to go to 160mph is the answer. I admit to being a little disappointed after the first run. Removed the deflector from the airbox cover... but that was as much time as available between runs. A jetting change was not going to happen unless I skipped a run...that was not going to happen!

I admit I developed short arm, tight pocket syndrome when it came down to dyno time and gambled on giving it a go. We had just got back from our biggest tour yet and time was as short as fun tickets.
There is more to be gained from tuning...20mph?...I think thats a pie in the sky fair goal but at this stage making 154mph next time would be great but looking at the machinery making those speeds I gotta wonder.

As to the bikes behavior at this speed. Without fault. Over 200kmh helmet under blade and chest were pressed to the tank but knees and elbows were the place to gain. Only just hitting 6th about 200 I struggled to get my feet out of the way...stock pegs are on borrowed time, touring gloves gave way to thinner ones with taped cuffs. The tacho was my peripheral focus and I got crueler as the day progressed. 2.5 k proved to not be far as ringing it's neck every gear I still gained 600rpm over the quarter. The last run i messed up the shift going 4th to 6th trying to get my feet to tuck and the times reflected that error.
The closed 7km straight was pretty smooth tho I had 22-25mm of front shock travel left after each run. A small undulation adjacent to the pits had the blown bikes pulling air.

Learnings, saying you've seen 260 or whatever aint nothing like holding it pinned long enough to watch tucking reflected in rpm gain. Anyone saying this and not having a chin impression in the top of their tank was probably buzzing their rear (a polite way of saying it?)
Like the man said "when the green flag drops the bullshit stops".

I know I now simply have to make what i got work. Pipes are sooty as f and the motor felt doughy above 8k. I'm guessing rich at the top. I could go mad with compression and duration but I still got to ride it to work.
The tune is so far away getting that right matters more than gas (gear aquisition syndrome) It should be better than stock but not.

Altho it wasn't as fast as I'd hoped, the hot babe from the IL4 crew next door said my bike (only vtwin there) sounded awesome!
Take the wins where you can I reckon

If landspeed is a drug...I'm a now it's junkie

Bucket list,
My trip home idle thoughts... fitting O2 sensors in the primaries to enable individual cylinder tuning and reseating/decarbing the valves and ports. The rubber carb mounts could be better and the airbox lid now has multiple cracks, practice tucking over smaller tank,better rear pegs, better fairing and shorter bars...
TUNE, TUNE, TUNE and maybe a better tuner.
Swampy
Posts: 80
Joined: Fri Jan 04, 2019 1:03 am
Location: NZ

Re: Your top speed

Post by Swampy »

Just found the GPS I left under the seat for the day

Image

The needle was about 240ish but I was a bit busy to really look.
The elevation is probably close, humidity nearer nil and the day 28-30c I guess...I got sunburn between runs.
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VT1000r
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Re: Your top speed

Post by VT1000r »

Swampy wrote: Sun Feb 10, 2019 11:59 pm Just found the GPS I left under the seat for the day

Image

The needle was about 240ish but I was a bit busy to really look.
The elevation is probably close, humidity nearer nil and the day 28-30c I guess...I got sunburn between runs.
Very respectable run :thumbup:
tony.mon
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Re: Your top speed

Post by tony.mon »

it looks to have been a good day, very nearly 150mph.

It should be quite easy to tune the carbs if you fit the Wideband sensors and display, as you only have to tune for WOT. A set of Flo-Commanders will make tweaking between runs much simpler than changing jets.
It's not falling off, it's an upgrade opportunity.
Swampy
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Location: NZ

Re: Your top speed

Post by Swampy »

Thanks for that, googling to understand the terms...have I been living under a rock much?
tony.mon
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Re: Your top speed

Post by tony.mon »

Sorry, WOT is wide open throttle.
Jet for flat out full throttle, nothing else matters for high speed runs or the drag strip.
Doesn't even matter if it'll tick over..

the O2 sensors? Probably easiest to fit wide band Llambda sensors in each downpipe,inked to a display showing real-time fuel to air ratio as you ride.

The flo commander is a device you add to the carbs which spoofs the main jet size, and is easily adjustable through the airbox wall with a screwdriver.

So you do a run, look at the mixtures, and tweak the jetting in seconds with no need to strip the tank and airbox off.
Easy....

Once you have the perfect setting, change the main jets to leave you in the middle of the range and you can adjust for weather and altitude on the fly.

You can also get a flo commander set for the secondary jets if you want to refine it even further, but for your use, why bother, you'll only be using the main jet circuit anyway.
It's not falling off, it's an upgrade opportunity.
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geoff996
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Re: Your top speed

Post by geoff996 »

On my first vtr a group of us were out my mate on his gsxr1000 said he was following me he had an indicated 150 asked me how fast i was going THE ANSWER WAS FASTER THAN YOU. 135 with the wife on the back with the lastest one
RIDE TO ENJOY
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