Got her on a dyno today...

[Blacksmith]

and am very unhappy about it. Now I knew not to go in with unrealistic ideas but I honestly thought 175 wasn't asking to much from what I thought was a good running stick bike. She only put down 165 over 6 runs. Idk yet about the torque, he has to update his software to figure the torque and will email me that and the graphs. He said my fuel map is a little off, she's running to rich in the midrange. Is this as bad as i feel like it is? Bike is stock with full M4 exhaust and PCV, I'm at sea level and temp this morning was mid 80's. I was really expecting a baseline around 175 and hopefully tweak a bit and hit 180

 

[Mythos]

A tight dyno could be the cause. Ask about your numbers compared to other busas dynoed at the same shop. A compression/leakdown test should tell you if your motor has some wear on it. I don't know what else would be the cause of a little loss in hp. My bikes are 12 years old. Never dynoed but the 14 does have barely in spec compression after 50k miles. I can't tell. I'd worry about it more if I were racing.

 

[WuzzaCBXRider]

My stock 06 turned 159+ twice and then just a tic over 160. I had both of my CBXs dynoed the same day at a BMW shop in San Jose. The Busa had around 35,000 miles on it then. Yours needs something for sure.

 

[Blacksmith]

He showed me the numbers on the last busa but they had a sparkplug issue and only put down 140ish. He said I could be losing 5 to 6 hp with my fuel map being off but it still seems a little low. He was straight up enough to suggest a Brocks economy flash instead of his custom pc5 tune but is like to be sure everything is right with my motor before doing that

 

[Mythos]

LOL I rode my busa nice and slow when it had an FI code and I couldn't tell there was any problem. It turned out one of the stick coil wires wasn't connected properly so it was running on 3 cylinders and it made about 0 difference that I could tell at low speed. At about 3000 rpm, I suppose the motor was making 20 hp instead of 27. I doubt you'll notice a 5-6 hp gain at peak rpm. I do not think 10 hp would be noticeable at peak rpm but maybe 15 if you ride the bike that fast often enough to be very familiar with what 175 hp should feel like. I would want the bike to run as well as it's supposed to but if you were happy with it as is, I wouldn't loose sleep over it.

Your hp is about right for stock, maybe that M4 exhaust isn't giving you that extra 15-18 hp all the manufacturers claim.

 

[Dopey]

He showed me the numbers on the last busa but they had a sparkplug issue and only put down 140ish. He said I could be losing 5 to 6 hp with my fuel map being off but it still seems a little low. He was straight up enough to suggest a Brocks economy flash instead of his custom pc5 tune but is like to be sure everything is right with my motor before doing that

I myself would not be ok with having someone touch or tune my bike if they are suggesting a generic brocks tune (especially when u don't have a brocks exhaust) over a custom tune. That in itself is a red flag for me to think they may not be confident in running the busa. Also if his last busa read 140 but had an issue with plugs and he knows this because it was fixed and he didn't retune or have it on the dyno after the fix to have the correct numbers again i think i would run away and try to find someone else. Just my thoughts on it and with those red flags in not sure I'd be to trusting in what his dyno said either.

 

[Mythos]

Yeah go to a tuner that does busas and a lot of them if you really need every drop of power. Maybe it's just that my bikes are 12 years old but I don't care much anymore what the dyno numbers are as long as the bikes are running smooth and they are still faster than I dare to go. The fastest I ever went was about 180 and the bike was not accelerating hard at that speed. If I were planning to go a lot faster than that, I would be more interested in what I could do about a small hp loss. We don't even know if your bike has a loss because that last busa was never tested after the problem got fixed. It might have shown 165 hp with good plugs too. Some dynos are high and some are low.

 

[Blacksmith]

I myself would not be ok with having someone touch or tune my bike if they are suggesting a generic brocks tune (especially when u don't have a brocks exhaust) over a custom tune. That in itself is a red flag for me to think they may not be confident in running the busa. Also if his last busa read 140 but had an issue with plugs and he knows this because it was fixed and he didn't retune or have it on the dyno after the fix to have the correct numbers again i think i would run away and try to find someone else. Just my thoughts on it and with those red flags in not sure I'd be to trusting in what his dyno said either.

In a small defense of the guy he was just telling me that ecu tunes are much better than tuning through the PC5 which is all he does. He doesn't go into the ecu, they being said he did lose my confidence when he told my riding buddy John that he turned his Roadstar 1700 VTWIN!! up to 9k trying to find the problem with his rear cyclinder.... Na bro you aint turned that motor to 9k especially when it's running like crap.

 

[c10]

If the dyno is not up to date , and can not give you a torque value it's a wasted run .
What I can tell you the busa runs rich is true . With my full system it was still rich with no tune first run on BCP's dyno . Rob took fueling out in many area's.
You didn't even lay down a stock gen 2 #

Shops are terrible about service to a dyno.
You have no way to double check them .
They know it to .

You want a # go run the 1/4 mile at a test n tune . Don't try to get a great time just focus on a clean leave and every shift to 5th . Croos line in 5th and tell us your mph .
That is a hp answer there

RJ can run a lazy 11.10 but mph 148.6

 

[Dennis]

If the dyno is not up to date , and can not give you a torque value it's a wasted run .
What I can tell you the busa runs rich is true . With my full system it was still rich with no tune first run on BCP's dyno . Rob took fueling out in many area's.
You didn't even lay down a stock gen 2 #

Shops are terrible about service to a dyno.
You have no way to double check them .
They know it to .

You want a # go run the 1/4 mile at a test n tune . Don't try to get a great time just focus on a clean leave and every shift to 5th . Croos line in 5th and tell us your mph .
That is a hp answer there

RJ can run a lazy 11.10 but mph 148.6

No shift to 5th!

 

[c10]

No shift to 5th!

That's gearing dependent what are you running Dennis? 17/44 ?

 

[Dennis]

That one was 18/44 or 45. With 17/44 you would need 5th, in fact most of 5th.

 

[ItsDooomz]

I'm currently at 17/48 and I use ALL of 5th at 155.6 mph. Completely stock motor.

 

[Dennis]

I'm currently at 17/48 and I use ALL of 5th at 155.6 mph. Completely stock motor.

You must have the rev limiter turned up. I'm surprised you go that fast in 5th if you are on a radial.

But anyway, the OP can certainly get an idea of hp with MPH and weight at the track, assuming he opens the throttle quickly and gets a good tuck.

 

[ItsDooomz]

You must have the rev limiter turned up. I'm surprised you go that fast in 5th if you are on a radial.

 

[Dennis]

View attachment 1625328

This one was 17/46 and was at the top 5th with the limiter bumped. Yours must have been screaming.

 

[ItsDooomz]

I like that ticket, hope to see something similar once it cools off. Ya, it's way up there. When I went from 17/47 to 17/48 It took me from 1.36 to 1.33 and at 153 mph it was up there pretty good. When I put on these new lightweight wheels it picked up well over 2 mph and it's screaming up there now, but shifting into sixth right before the mile per hour cone doesn't make sense. It just slows it down. I shift at 11,100 actual and I can't gear it anymore aggressively, it's toting the wheel now. Thats about all I'll get at 67" in Florida's summer heat and humidity. I'll have to take it to 17/46 or maybe 17/45 when it cools off this fall and winter and starts making power.

 

[c10]

I like that ticket, hope to see something similar once it cools off. Ya, it's way up there. When I went from 17/47 to 17/48 It took me from 1.36 to 1.33 and at 153 mph it was up there pretty good. When I put on these new lightweight wheels it picked up well over 2 mph and it's screaming up there now, but shifting into sixth right before the mile per hour cone doesn't make sense. It just slows it down. I shift at 11,100 actual and I can't gear it anymore aggressively, it's toting the wheel now. Thats about all I'll get at 67" in Florida's summer heat and humidity. I'll have to take it to 17/46 or maybe 17/45 when it cools off this fall and winter and starts making power.

What is your rig weighing in now as a full time drag bike ?

 

[Dennis]

I like that ticket, hope to see something similar once it cools off. Ya, it's way up there. When I went from 17/47 to 17/48 It took me from 1.36 to 1.33 and at 153 mph it was up there pretty good. When I put on these new lightweight wheels it picked up well over 2 mph and it's screaming up there now, but shifting into sixth right before the mile per hour cone doesn't make sense. It just slows it down. I shift at 11,100 actual and I can't gear it anymore aggressively, it's toting the wheel now. Thats about all I'll get at 67" in Florida's summer heat and humidity. I'll have to take it to 17/46 or maybe 17/45 when it cools off this fall and winter and starts making power.

That sounds very similar to the setup I was running at the time. I ended up running a 5.50 flat in good air that fall, and also I tried MR12 which got me to a 5.50 flat in normal air.

 

[ItsDooomz]

What is your rig weighing in now as a full time drag bike ?

I'm not sure, It's still stock OEM body work, stock tank, headlight and tail light. When I switched wheels I took them off the bike with the tire, rotor, sprocket carrier and sprocket attached, put them on the scale, swap the wheels, got them ready to go back on the bike and weighed them again. It's a ridiculous amount of unsprung/rotating weight to get off the bike. (See pics below) Instantly picked up a tenth and over 2 mph. I'll scale it next time they have the head attached at tech.

OEM rear

OEM front

Carbon rear

Carbon front