Do you want more power? come in.

very glad so many people come to discuss this topic. the reason I post this thread is I do not have horsepower machine, can not tell how much power increase or decrease. I wish somebody on this website maybe have horsepower machine or something like this to test, or somebody do the same thing and tell me what you feel. I have a p-box, will try 0-100km acceleration, wish the result is good.
 
robinyu said:
I do some modification to my ST, let me show you.
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This mod reminds me of the airbox that Turbo Tom (I think) modified,,, with extra inlet channels cut into the lid. There are posts on that project somewhere. The goal was 2 fold,, to increase airflow at max throttle openings,,, and to make an inlet sound change/improvement. Interesting,,, but I have no experience on how well it might meet those goals. cheers,, CAt'
 
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dwalby said:
Agree with Larry's comment that its not necessarily bashing, just giving honest feedback.

Regarding the 'tries something different' angle, if given the choice between a team of professional engineers who design bikes for a living using millions of dollars of test equipment and a guy on the Internet with a Dremel tool, I'm going to tend to favor the engineering team. Not saying its impossible for the guy with the Dremel tool to be onto something, but its not likely either. And, just because its 'different' doesn't imply its necessarily better. Honda engineers know how to make a hole bigger too, yet they chose not to, there's probably a sound reason behind that decision.

Haven't heard it mentioned much in years, but in the old days it was usually a case of "I'm just removing all the restrictions caused by EPA regulations, so it will run better" even though motorcycles have never been tested for emissions in California, ever. It didn't seem to work all that well in the carbureted days, and in the EFI days its even less likely to improve things.
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They check emissions here in Costa Rica and I just had my inspection 2 weeks ago. The tech checked his rod 8 times, two per muffler hole because he said, “it’s not working. I have no reading”.

and although the engineers design bikes for a living, I’d like to slap the one who decided to put the clutch slave cylinder behind the motor and then make unsuspecting shop customers pay for an engine pull to change/rebuild it when it is not necessary to remove the motor

in regards to the post, if it ain’t broke..........but to each his own. I have a friend who put a V8 in a Gremlin just cuz he could
 
Was not too hard to find the Turbo Tom airbox mod thread. There are photo's in post #1. Interesting,,, CAt'

Let the Testing Begin - Air Box Mod | ST1300 Related

As someone who just can't seem to leave well enough alone I modified something else on my bike, the air box. It started out as just a trip to Turbo City to see Tom about exchanging my FPR because I changed something else on the bike, added Staintunes, after installing the FPR with no intention...
www.st-owners.com www.st-owners.com
 
Conceptually, HP is a measure of how fast you can apply torque. You might think of torque as answering the question, "Can you do it?" And horsepower answering the question, "How fast?"

The formula is (torque*rpm)/HorsieConstant. We could use a mouse constant or an elephant constant if we wanted to, but most people use the horsey constant. If you want to know the horsey constant, look where torque = rpm. That's where the horsey constant and rpm cancel each other out and hp=torque.

So, when you remove weight that allows faster application of torque, you can expect the possibility of a horsepower gain. But beware, it gets a little difficult to paint a neat and consistent picture. Weight off the frame is least effective. Weight off rotating objects like wheels and cranks is far, far more effective. Weight off reciprocating items like pistons and con rods is the most effective.

Removing the stator off my lightweight super twin, going to a total loss system, was dyno'd to be something like +5 hp in first gear, descending to no benefit in 5th gear.
 
Catmandu2 said:
Was not too hard to find the Turbo Tom airbox mod thread. There are photo's in post #1. Interesting,,, CAt'

Let the Testing Begin - Air Box Mod | ST1300 Related

As someone who just can't seem to leave well enough alone I modified something else on my bike, the air box. It started out as just a trip to Turbo City to see Tom about exchanging my FPR because I changed something else on the bike, added Staintunes, after installing the FPR with no intention...
www.st-owners.com www.st-owners.com
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Pete in PA said:
Without installing the air box lid screws I revved the engine up and down around 7k rpm and felt the extreme suction pulling the lid down. The engine IS starving for air. The factory opening IS undersized. That intake horn at the front is only a little bigger than 1 throttle body diameter.
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I read this thread before I cut my airbox, but I doubt the filtration effect. so I try find another way to enlarge the air intake.
 
@Okieprobably read the Kevin Cameron articles FIRST, in the old Cycle magazines.
I always read Kevin last, much to my everlasting shame today. If I had only known then, how smart he is...
 
robinyu said:
very glad so many people come to discuss this topic. the reason I post this thread is I do not have horsepower machine, can not tell how much power increase or decrease. I wish somebody on this website maybe have horsepower machine or something like this to test, or somebody do the same thing and tell me what you feel. I have a p-box, will try 0-100km acceleration, wish the result is good.
Click to expand...
Dynamometers are big expensive machines. They are not typically owned by individuals, but by custom engine shops and racing teams. Unless someone works for one of these companies, it is not likely that anyone would try the mod. According to the Turbo Tom thread, he did exactly that - dyno'ed his bike before and after. There is a lesson in his results.
M Rogers said:
and although the engineers design bikes for a living, I’d like to slap the one who decided to put the clutch slave cylinder behind the motor and then make unsuspecting shop customers pay for an engine pull to change/rebuild it when it is not necessary to remove the motor
Click to expand...
Every engine design is a compromise, with influence from many quarters (i.e. bean counters). I used to say there was enough room under the hood of our Volvo 122 for me to curl up and take a nap...comfortably. Yes an exaggeration, but that car had no A/C, electronic controls, etc.
 
M Rogers said:
They check emissions here in Costa Rica and I just had my inspection 2 weeks ago. The tech checked his rod 8 times, two per muffler hole because he said, “it’s not working. I have no reading”.

and although the engineers design bikes for a living, I’d like to slap the one who decided to put the clutch slave cylinder behind the motor and then make unsuspecting shop customers pay for an engine pull to change/rebuild it when it is not necessary to remove the motor

in regards to the post, if it ain’t broke..........but to each his own. I have a friend who put a V8 in a Gremlin just cuz he could
Click to expand...
I had to reread the "checked his rod 8 times......." sentence several times to get the proper context here. Thanks for that update about Costa Rica emission checks :biggrin:

Although the service manual does describe having to remove the slave cylinder for rebuild it does not have to be removed. With a little patience and a modified wrench that can get on the retaining bolts the remove & replace can be done with engine in the frame.
 
Larry Fine said:
I have a friend who used to race a Corvair with a mid-engine mod. It had a 427 where the back seat used to be.
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I have one of those chassis's,,, with the mid-engine corvair flipped/spun transaxle. It was originally set up for a 327 screamer. But since my elbow would wind up against the crank pully,,, I have re-set it up to use a vortec V6, which is in-line with the transaxles max torque limitations anyway. Will be fun,, one day soon,,, I hope,,, CAt'
 
Catmandu2 said:
I have one of those chassis's,,, with the mid-engine corvair flipped/spun transaxle.
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This one used a kit that replaced the front cap of the Muncie 4-speed transmission with an adapter that connected the new bell housing to it, and a new transmission input shaft replaced the original that ran through the hollow output shaft.

The original transaxle's bell housing, which was part of the differential case, still hung in the now-empty engine compartment by a couple of lengths of angle-iron, since there was no longer an engine to keep everything in place in the car.
 
OH lordy I am having ZX12R A vs B model snorkle nightmares again :rolleyes:

The question would be does the OEM snorkle have any ram air effect and if so would removing effect the torque curve ? Then would opening the air "hole" effect the torque curve in a postive way ? The nightmare comes in when people use static dyno graphs or zero data to debate torque curves when ram air is "possibly" involved :(

I like the ST1300s curve with no cats and a K&N :)
 
Catmandu2 said:
Kaz,,, are you referring to the mod that Turbo Tom developed for the lid, some time ago ?? Or the mod's that Robin has recently trialed,,, on the airbox floor ?? CAt'
Click to expand...

I was referring to the Turbo Tom lid mod? I had never heard of it and wondered why it feel out of favour ?
 
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