Staintune

[misterprofessionality]

IIRC the weight difference between the stock Honda muffler and the Staintune was something like 3 or 4 pounds, as measured by forum members, and the gain in hp was like 3 or 4 hp as measured by forum members dyno reports.

I don't think anyone ever gained 10 hp with an exhaust change only, even a complete system.

Back in the day, when they were putting larger jets in the carbs, opening up the air restriction with pod filters and then adding a freer flowing pipe they might have gained more than 10 hp. Cams have always been the secret to gaining hp. Well that and increasing displacement aka Big Bore Kits. nothing like that available for the CB1100.

Like Powerdubs said, altering gearing is a really good/inexpensive way to make it FEEL like it has more hp even if it doesn't.

if the actual available power doesn't change, would you say I could get the same effect by simply altering my riding technique?

I have been modifying engines in cars and motorcycles for a few decades.

Not to get off topic- but I have done port jobs, bigger valves, countless camshafts, custom intake manifolds, numerous headers, high flow cats, mufflers, jetted carbs, bigger carbs, bored out TB's, individual TB's, bigger injectors, ecu tunes... you name it. And yea literally hundreds of dyno runs and several hundred drag strip runs.

What I can tell you- most important, don't believe manufacturer #'s.

2nd thing- don't add #'s you see listed for products together for a lump sum.

3rd thing- most larger power gains on old engines are not available anymore from a design stand point.

The port design, valve sizing, filter/intake cfm, exhaust design/cfm, and yes even fueling and ign curves are already near optimal from the factory on just about anything- right down to a lowly Kia.

Long gone are horrible inefficiencies from log manifolds, 2b carbs, casting slag, 2v heads... all you can really do is tweak a little to get back what they factory trimmed for emissions, fuel economy, noise, and low octane fuel. Not much.

You can throw the parts you are talking about (full exhaust / ecu flash / intake mods ) and after having spent an easy $1,000+ you will end up with less than a 10whp gain. While the bike will feel and sound better- the difference in actual acceleration won't be enough to make up any difference in rider ability.

What I mean by that- take your bike when done- and another rider on a stock bike. There is a good chance the stock bike would still win a race- something as simple as launch rpm, or a difference in shift points could easily make up the difference. And that is talking best case scenario- straight line staged start. In the real world you are rolling on the throttle, in who knows what gear.

So- back to gears- an engine makes the power, all the gearing does is manipulate that power. Like a breaker bar on a ratchet or tire iron. Changing a sprocket has ZERO effect on the power the engine makes, does not change anything about how much power it makes at any rpm.

Gearing changes how that power is sent from the engine to the wheel. Like a 10-speed bicycle. You changing gears on the bicycle doesn't make your legs any stronger. Changing the sprocket on the motorcycle is the same. You know when you downshift from 4th to 3rd to accelerate? If you put a larger rear sprocket or a smaller front- you are shifting all 6 gears downward.

Also- people get confused on tq and hp. They are one and the same. In fact- engines don't make hp- they make tq and then you calculate hp from that.

HP=TQxRPM/5252

So if you know how much tq an engine makes at any rpm you can figure out the hp # for that rpm as well.

Have fun, do what you want to do..that's how you learn, but don't be surprised at the results and placebo effect of a lighter wallet. I'm not saying there isn't power potential in 1140cc, I'm saying the bottleneck is not the normal easy parts everyone is doing.

If you want to learn how an engine works, especially in the realm of hotrodding them and making power or moving power bands around- this is not the engine to start on.

Thanks for the rundown. I'm sure it will save me money in the end. And believe me, I don't have any ambition to learn this stuff/do it on my own. Every bit of this is outsourced to a mechanic (like you!), I just need to know what to ask for. My fear is that i'm going to ask for something stupid, and the mechanic, being a businessman, will just give it to me and happily take my money, the same way I would if somebody asked me for something stupid in their kitchen.

Honestly, I'm not even upset if there's no way to significantly improve the CB11's performance, I just wanted it to be everything it could be. From what you guys are saying, i'd get the most gains from just shedding weight and getting better tires, which I can wrap my head around a lot easier.