200mph - Can I Get There?

[05calibusa]

I'm preparing for Mojave and now I'm second guessing whether I will hit 200mph in the mile.  Earlier this year, I completed my engine build on my Gen1 1441 and the dyno shows that I can put 220Hp to the ground with 135ft-lb torque and over 100ft-lb through the entire rpm range.  I also have data logging and tuning capability, so I can log my runs and adjust my A/F.  I have two concerns:

1.  I plug all the numbers in the top speed calculator, and even with 18/38 sprockets @ 9,500rpm max power it only gets me 198mph.  With this gearing, the theoretical point where I would reach 200mph is 9,600rpm, so based on the calculator, it means that I would need a taller gear or more rpm to get beyond 200mph.  Obviously, the calculator does not account for Hp, Torque, rider weight, etc. (not saying that it should, just making the point).  The reason I say that is; I'm still making good power all the way to my rev limit, even though it starts to drop off after 9,500rpm (or at least that's what it looks like on the dyno sheet...more on this in my next point).

2.  My rev limiter is set to 11,500rpm, but my dyno sheet shows the fuel cut around 10,500rpm.  I'm wondering why there is a 1,000rpm delta between what I think is in the ECU and what the dyno sheet is showing.  Does this mean that my peak power is at 10,117rpm and not 9,117rpm like it shows on the dyno sheet?  This really puzzles me and it is important if I should believe the top speed calculator, because that extra 1,000rpm could mean making 200mph, or not.

I'd like to hear from some tuners about the 1K rpm delta between the dyno and my rev limiter.  I would also like to know if any others with a similar setup have hit 200mph in the mile.  In hindsight, I'm thinking that maybe I should have degreed my cams around 108/109 instead of the 106.5/108.5 that they are currently at, in order to bring my peak power up to a higher rpm.  However, I am still second guessing the dyno sheet and where it is showing my peak power...that is the question that I really need to answer. 


     

[fvance]

What cams do you have in it? What injectors? It looks like you are hitting the rev limit at 10800 which is stock?? My gearing spreadsheet says 18/38@9600rpm will get you 193mph, it is very accurate. An NA busa is not going to pull much past peak hp rpm, in sixth gear. You will need a 19/38 to get you over 200mph.

[RansomT]

How is your rev limit raised and who did it?

Fred, from the look of the curve it looks to me stock cams.

[05calibusa]

Rev raised to 11.5k and top speed limiter removed in ECU Editor.  My tuner and I both verified.

[2fast4u2c]

Just a tidbit of info.  Just because a gearing calculator say you should go a certain MPH, does not mean what so ever that you will even come close.  Be prepared for a small dose of LSR humility when you come to the track.  Rolling resistance, roll out of rear tire, wind, rider ability, aero dynamics of riders position all play a very important role in your ability to reach 200.  I have seen many many riders on their first time out expect 200 and go home humbled at 186 and change.

Just a tidbit.  I'm sure RansomT will concur.

Guy

[05calibusa]

I did 172mph last year (rookie) when the bike was stock (only basic mods and a tune).  I know where you are coming from.  I figure if my peak power is at over 10k at least I have a shot.  If it's 9k, then maybe not.  That's why I'm trying to figure out of the dyno sheet is right or if it's off by 1k.
Thanks

[knecum]

no sense raising limiter much pass peak hp rpm. Maybe 300 more. Unless you want to take is back apart when it misses a gear.

[gsx-rboy750]

Just a tidbit of info.  Just because a gearing calculator say you should go a certain MPH, does not mean what so ever that you will even come close.  Be prepared for a small dose of LSR humility when you come to the track.  Rolling resistance, roll out of rear tire, wind, rider ability, aero dynamics of riders position all play a very important role in your ability to reach 200.  I have seen many many riders on their first time out expect 200 and go home humbled at 186 and change.

Just a tidbit.  I'm sure RansomT will concur.

Guy

Totally agree. I have to gear 10-15 mph over for clutch slip, tite slip etc all like Guy said.

[05calibusa]

no sense raising limiter much pass peak hp rpm. Maybe 300 more. Unless you want to take is back apart when it misses a gear.

I agree with that, but I'm trying to understand if my peak is at 9117 or 10117.  I know we hit the rev limiter on the dyno, but the graph stops (cuts out) around 10.5k and my rev limiter is set to 11.5k.

[RansomT]

A couple of things come to mind:

I'm not acquainted with that type of dyno, but my dyno has the option that allows you to calculate engine RPM based on rear wheel speed.  If the dyno operator didn't know that your rev limiter was raised, then he could have adjusted the settings to match 10.8k rpm.  Normally when that happens, TQ numbers will be higher than actual while HP numbers will be correct except for RPM.

Cam pin problem could case the cam sensor to read a false limit.

If it was me, I would get it checked at another dyno.  $50 or so to confirm if it is a problem or not would be will worth the time and effort to hunt down a ghost.

[knecum]

also if your clutch switch is bypassed it will hit a early limiter, and sometimes if you have a c92 code if you have aftermarket tank and no fuel level working I think I heard it sends it into a neutral map and early limiter as well.. 11,200 on factory tach hits limiter which is 10,800 actual ..so figure tach reads 500 higher.

[05calibusa]

also if your clutch switch is bypassed it will hit a early limiter, and sometimes if you have a c92 code if you have aftermarket tank and no fuel level working I think I heard it sends it into a neutral map and early limiter as well.. 11,200 on factory tach hits limiter which is 10,800 actual ..so figure tach reads 500 higher.

2005 busa, clutch switch is not bypassed, no codes.  Stock fuel tank, with internal regulator and Bosch pump.

[Got-Busa?]

Where did he tie in to get the RPM reading from the ECU/tach?

I'd slap it on another dyno just for the heck of it and see what it says.

Also, what size rider are you? 

[fvance]

Again What cams and injectors?

[05calibusa]

Again What cams and injectors?

.395/.378 cams, stock injectors and fuel rail, crush mod on regulator, bosch pump, ward head.

[knecum]

customer with 200hp  gen 2 just went 199 at loring in the mile and 203    in  1.5 

[05calibusa]

Where did he tie in to get the RPM reading from the ECU/tach?

I'd slap it on another dyno just for the heck of it and see what it says.

Also, what size rider are you?

Not sure where the rpm was coming from.  We had the ECU Editor connected during the dyno sessions, but not sure about the interface with his dyno.

I go about 6'1", 205lb...not the ideal busa jockey, but what the hell, I just wanna go fast.  I figured after dumping nearly $6g's into my bike, it would surely pull my fat arse along at 200mph.

[scott g]

customer with 200hp  gen 2 just went 199 at loring in the mile and 203    in  1.5

In the year 2000, LARRY FORSTALL became the first
new member of the Bonneville 200 MPH Club
 on his 2000 Hayabusa, on which
Bob Carpenter did a bunch of work.

I rode the bike a couple of days later,
and saw an "exit speed" of 211 MPH.

The Dyno at sea level showed 211 HP at the rear wheel.

The next month , I made twenty four (24) runs
at Maxton over 200 MPH, best was about 210 MPH.

Sold the bike to another racer, and
he made 200 MPH both at Maxton and at Bonneville.

All with 211 RWHP, 1397cc., and STOCK bodywork.

If you have 220 HP, decent gearing, decent tuck,
ordinary size and weight,  and good air,
you should go WAY over 200 MPH.

Best of luck, my friend.

Look for the finish line !

[05calibusa]

Now that's encouraging!  All I want is my 200mph club t-shirt and my name on that list.  I will get there one way or another.  I did this build myself and the bike is running sweet.  Much of what I learned came from the good folks on this forum and I thank you'all for that. 

I may have to get it back up on the dyno to figure out this peak Hp vs. Rpm issue.  I'm also going to bring an extra set of gears like 18/38T or 19/36T.

[Got-Busa?]

Not sure where the rpm was coming from.  We had the ECU Editor connected during the dyno sessions, but not sure about the interface with his dyno.

I go about 6'1", 205lb...not the ideal busa jockey, but what the hell, I just wanna go fast.  I figured after dumping nearly $6g's into my bike, it would surely pull my fat arse along at 200mph.

I think you have a very good shot at it.  Make sure your gearing is correct and I think you should be fine if weather conditions are in your favor.

I'm bigger than you and did it with less power...

[entropy]

unless that motor is sick, there is something very wrong with that rpm scale.

what kind of dyno is it?

as others have said, put it on a Dynojet where rpm is is taken from the ECU...

[knecum]

customer with 200hp  gen 2 just went 199 at loring in the mile and 203    in  1.5

In the year 2000, LARRY FORSTALL became the first
new member of the Bonneville 200 MPH Club
 on his 2000 Hayabusa, on which
Bob Carpenter did a bunch of work.

I rode the bike a couple of days later,
and saw an "exit speed" of 211 MPH.

The Dyno at sea level showed 211 HP at the rear wheel.

The next month , I made twenty four (24) runs
at Maxton over 200 MPH, best was about 210 MPH.

Sold the bike to another racer, and
he made 200 MPH both at Maxton and at Bonneville.

All with 211 RWHP, 1397cc., and STOCK bodywork.

If you have 220 HP, decent gearing, decent tuck,
ordinary size and weight,  and good air,
you should go WAY over 200 MPH.

Best of luck, my friend.

Look for the finish line !

FYI I built that motor for Larry when I worked for Bob!, It wasn't a 1397 it was a 1330 wasn't it for 1350 class?

[05calibusa]

unless that motor is sick, there is something very wrong with that rpm scale.

what kind of dyno is it?

as others have said, put it on a Dynojet where rpm is is taken from the ECU...

It's a Land & Sea DYNO-mite w/ DYNO-max software.  Pretty sure it's one of the "800" series MC/ATV models. 

http://www.land-and-sea.com/motorcycle-dyno/motorcycle-dyno-specifications.htm

[scott g]

customer with 200hp  gen 2 just went 199 at loring in the mile and 203    in  1.5

In the year 2000, LARRY FORSTALL became the first
new member of the Bonneville 200 MPH Club
 on his 2000 Hayabusa, on which
Bob Carpenter did a bunch of work.

I rode the bike a couple of days later,
and saw an "exit speed" of 211 MPH.

The Dyno at sea level showed 211 HP at the rear wheel.

The next month , I made twenty four (24) runs
at Maxton over 200 MPH, best was about 210 MPH.

Sold the bike to another racer, and
he made 200 MPH both at Maxton and at Bonneville.

All with 211 RWHP, 1397cc., and STOCK bodywork.

If you have 220 HP, decent gearing, decent tuck,
ordinary size and weight,  and good air,
you should go WAY over 200 MPH.

Best of luck, my friend.

Look for the finish line !

FYI I built that motor for Larry when I worked for Bob!,
It wasn't a 1397 it was a 1330 wasn't it for 1350 class?

I thought you built the motor Steve,
but did not want to "blame" you without being sure.....

I owned the bike for less than a year,
and never had to take it apart.
So, no direct memory of the displacement.

Great engine, took four (4) riders
(Forstall, Yacoucci, Guthrie and Haven) over 200 mph
with NO major work, and more than 50 full power passes.

You should build engines for a living !

Scott

[knecum]

customer with 200hp  gen 2 just went 199 at loring in the mile and 203    in  1.5

In the year 2000, LARRY FORSTALL became the first
new member of the Bonneville 200 MPH Club
 on his 2000 Hayabusa, on which
Bob Carpenter did a bunch of work.

I rode the bike a couple of days later,
and saw an "exit speed" of 211 MPH.

The Dyno at sea level showed 211 HP at the rear wheel.

The next month , I made twenty four (24) runs
at Maxton over 200 MPH, best was about 210 MPH.

Sold the bike to another racer, and
he made 200 MPH both at Maxton and at Bonneville.

All with 211 RWHP, 1397cc., and STOCK bodywork.

If you have 220 HP, decent gearing, decent tuck,
ordinary size and weight,  and good air,
you should go WAY over 200 MPH.

Best of luck, my friend.

Look for the finish line !

FYI I built that motor for Larry when I worked for Bob!,
OIt wasn't a 1397 it was a 1330 wasn't it for 1350 class?

I thought you built the motor Steve,
but did not want to "blame" you without being sure.....

I owned the bike for less than a year,
and never had to take it apart.
So, no direct memory of the displacement.

Great engine, took four (4) riders
(Forstall, Yacoucci, Guthrie and Haven) over 200 mph
with NO major work, and more than 50 full power passes.

You should build engines for a living !

Scott

. If I remember right he entered in the production class. But you did buy another bike also.. which one did dash buy?  You right I should build them for a living!!