help with debaffle

[Rudeboy]

can anyone post a cross section drawing of the muffler and baffle?
the Vulcan was easy to debaffle simply by cutting through the end plate.
I would like to know how the moise baffle is aatached inside the stock exhaust on the GZ.

[Rudeboy]

here is a link to a picture of a baffle from a 800 after removal

http://www.ipass.net/dmvinson/baffle2.jpg

here is a link to the site that showed me how to do that baffle removal

http://www.ipass.net/dmvinson/pipemods.html

[Easy Rider]

can anyone post a cross section drawing of the muffler and baffle?


After drilling some holes in the (VERY HARD) back plate and then plugging them up again, I would encourage you to consider this change VERY carefully.............very carefully.

I have heard a scant few people who have replaced the pipes altogether who seem to be happy with the result.
Those who have tried to modify the stock muffler/pipes seem to end up less than happy.

Any significant change in back pressure may adversely afftect performance......the thing is pretty lean to begin with.
Reducing the intake restriction results is a DRASTIC loss of performance.

Good luck; be careful! :tup:

[Rudeboy]

well the carb is already in need of a good cleaning
so I already bought the new jets
and the stock exhaust is already damaged
it has rattle in it as if someone already tried to punch through the baffle
so before I spend the money on a dunstall which I am already sure I will do I thought I might try to debaffle the stock and rejet and mod airbox all in one week or so.

[trykemike]

Hey rude

I have searched for such a diagram on the web . No luck.

I have drilled 4 evenly spaced 7/32 holes inside the inner ring on the back plate. It gave me the sound I was looking for.

what size main jet are you planning to install ?

I suggest that you mod the air box in stages like maybe drill a 1/2 inch hole in the hood on the filter entrance then progress after testing.

A mechanic suggested using a 122.5 main jet instead of a 125 that I purchased but have not installed yet . I have 4 of those jets.

[Easy Rider]

I suggest that you mod the air box in stages like maybe drill a 1/2 inch hole in the hood on the filter entrance then progress after testing.


Mmmmm.....not sure I follow that. The "hood" attached to the filter is easily removable; it just pops off with a little pry. It has virtually no impact on performance or fuel mixture. It's there just to help keep out water, bugs, etc.

One needs to be careful with actual air box mods. as the air box is BEHIND the filter, not in front of it......air flow wise. A less restrictive filter (don't think there is any such thing available) or complete air box replacement seem to be the only practical choices. I personally don't consider the complete replacement to be practical either.

Anyhow, whatever you end up with air-intake wise, you just need to be sure that there isn't a path for un-filtered air to get to the engine. :tup:

[jonathan180iq]

K&N SU-5589 is a direct replacement.

Hope you don't screw something up.

[Easy Rider]

K&N SU-5589 is a direct replacement.


Except more free-flowing, right?
I stand corrected.

[jonathan180iq]

Yeah it's less restrictive. It was designed for the GS-500 and a couple of other big Suzuki cruisers but we have the same air filter as they do. The opening inlet which lets in air is a little fatter than the stock filter and the filter element flows more than stock. I mean, it's a K&N. That's what it's supposed to do.

You're going to have to re-jet. If you feel like taking that project on, I'd at least go this route and not waste my time boring holes in the muffler and modding the air box.

Just go ahead a get the replacement muffler and drop in this K&N.

[Arcade]

I drilled 4 evenly spaced 1/4" holes on the OUTSIDE of the inner ring and switched the filter from facing backwards to facing forwards. Huge improvement in top speed and no adverse effects on the fuel/air mixture. No rejetting required. On the downside, it does sound a bit different - like it's got a whole in the muffle (which it does).

[Easy Rider]

Huge improvement in top speed

Right!

I encourage you to repeat whatever tests you did to come to that conclusion.

If it turns out to be true, you will be the only person in the history of the world to get any significant change from the mods that you listed.

Oops, I'm sorry. There was ONE other person who posted results like that here.......along with some other rather..mmmm...dubious claims and then vanished.

[Arcade]

All I've got is personal experience. I went from barely reaching 60 going downhill with a tail wind and fully open throttle to 65-68 on a flat road with a little bit of throttle left. I haven't done anything else to the bike except remove the front fender and the rear seat.

[jonathan180iq]

Here's the thing. If anything, removing that little deflector from the air filter opening would actually slightly lean the air/fuel mixture. Less gas and more air equals a less complete explosion, resulting in less power. Simply rotating it from front to back doesn't change the flow characteristics at all. The air filters sucks it air from behind the plastic side cover. So, you aren't getting any RAM effect either.

It's more likely that the atmospheric conditions on any given day were different. As such, a variation of 5 mph here or there is not unheard of.

When I first got my bike, I could ride at 80mph all day long. Then, it started slowing down to maxing out around 70-75. I attribute this to the engine breaking in and loosening up a bit. I haven't seen 80 in months and that was in the draft of a transfer trailer.
My new top speed doesn't really count as I have a different gear ratio. Still, there are days when I can't get the bike above 60 and days when I can still hit 70 and I gave up on "power" increases a long time ago. I rarely ever need to go faster than 55 and that is a speed that this bike is really made for.

[Arcade]

I'm not a mechanic, but it seems to me that if you help with the airflow, from intake to output, even a little better air flow might help things out. Releasing the backpressure in the muffler means less restricited air flow, add in allowing better airflow through the airfilter by turning it around. There is no practical way (for me) to measure the increased airflow through the filter since it is under the side cover but even minute pressure from outside forcing (a strong word that I am using to illustrate a point, in actuallity its probably a little closer to the drips from a faucet when you don't shut it off tight enough) air in causes the engine to work less hard. Anything you can do to decrease the workload on the engine is good, as far as I am concerned. 5 mph in a car or larger bike isn't much of a difference, granted, but for me, 5 mph constitutes a huge improvement on this bike.

I'm from S. Georgia, atmospheric conditions dont change THAT much on any given day down here. From mid/late spring to late fall you can expect 80-95% humidity, 75-95 degrees, and rain just about everyday, when we're not in a drought. Barmeteric pressures stay relatively the same except just before and just after a big storm (which we haven't had many of recently, hence the drought).

I would LOVE to get 70-75 mph on my bike. It just aint gonna happen unless I put a big bore kit on or perhaps swap the muffle out and rejet. I am seriously considering the 16T front sproket if i can find one.

One thing I have noticed from reading over the boards, everybodies bike is a little different. It even seems the "stock" bikes achieve different speed ranges. I don't know the why's or werefore's or the why not's for that matter. All i can say is what I've done to mine and what improvements (or lack of) that I've seen. If i had dyno'd it before and after and had some real empiricle evidence that could be repeated over and over, then there would be something to argue over. As it is, all I've got is my observations. Take it for what's it worth, love it or leave it, opinions are like a certain body part, everyons got one and they all stink, (add whatever cliche you want here).

[jonathan180iq]

You're right. You are certainly entitled to your opinoin and if you are getting an extra 5 mph and attribute that putting holes in your muffler and moving a plastic lid from the right to the left, then so be it.

I will go ahead and tell you that the 16T sprocket will not make your bike any faster. It will, however, lower your cruising speed RPMs and make the bike feel not so "buzzy" at faster speeds. I'll never go back.

On a simple carbuerated engine changing the airflow and letting the bike breath better will, indeed, increase some power output. However, an increase in airflow on a carbed engine will result in a decrease in power if you don't properyl adjust the fuel flow, also known as "jetting" at the same time.
That being said, it is possible that the generic jetting from the factory tended to be a little rich (higher fuel ratio than is ideal (14.7:1) and in doing so your adjustments slightly leaned the mixture and you are actually realizing an incrase in power output. That's possible. It's just not common. The factory setting tends to be fairly lean.

One last thing, there is no big bore kit for this bike. Don't get your hopes up. Does that mean that you can't spend tons of money have something retro-fitted? No. But, if you spent $1000 on something that might increase your power output by 10%, it still won't really be worth it.

[Easy Rider]

I haven't done anything else to the bike ***EXCEPT*** remove the front fender and the rear seat.

(Emphasis added)

Just removing the LARGE front fender might get you 5 mph on the top end. Lots of wind resistance gone.


I'm not a mechanic, but it seems to me that if you help with the airflow, from intake to output, even a little better air flow might help things out.

Well, if it was that simple and all it took to make more power was more air.............then everybody would be a mechanic. :) Alas, it isn't that simple. You gotta add more gas WITH the air or it's counter-productive.

Don't believe me? Just take the (very restrictive) air cleaner element OUT and go for a short test drive. Don't get out in traffic though because it will run like CRAP and you might get squashed. We've pretty much beat this topic to death in the past 18 months or so.

Want to do another test?
Put the front fender back on and see what happens to your top speed.


It just aint gonna happen unless I put a big bore kit on .....

That sounds familiar. Are you sure you haven't been here before ??? :??:
(Just kidding!)

[Water Warrior 2]

Go for a ride in the rain with no front fender. The fender is there to protect you and the bike from anything the tire kicks up.

[rusty rider]

That's like asking a pony to carry the horse's load. :roll: The GZ I ride tops out in the mid 70's, but it is most comfortable to ride at about 60 mph. The GZ is a commuter bike made for urban riding, and back roads. It can be used for many purposes though. I have put 1500 miles on mine in about 2 months most of them on back roads and 2 lane highways. The best way I know to ride any faster would be to get a larger bike, or one that is made for speed like Kawasaki's Ninja 250 it will run about 100 mph and doesn't cost much more than the GZ. As for myself I'll just keep cruising :rawk:

[deadman13]

that had been sitting for 6 years. i had it up to 66ish the other day before hitting fifth gear and all ive done was a few holes and took the hood and rear seat off. im 6 ft, 240, and i have a moped tag on my bike just for fun ( i used to have a pagsta...). ive done wheelies on it (albeit not big or long ones, but hey, you take what you can get) and love this thing. mine seems to have a little bit of a rumble in the exhaust now, not annoying but more than youd expect. i did drill a hole on the right side and hit the second plate, i drilled through it too. maybe that was a big help, who knows. anyone really going to dyno one of these? hell an dyno run would cost more than i paid for the bike. actually, the new tires and chain cost more than the bike...

[Rudeboy]

I cut open the filter to allow more air in
then I put in a new larger main jet
then I shimmed the needle, (although I don't know if this did anything
then I adjusted the pilot jet
then the exhaust

the exhaust was rattling, what was rattling, who knows
so we removed the whole exhaust
cut the pipe in front of the muffler
and out fell a 6 inch long 1/2 inch sttel rod with a sharp point on the end
we figured someones "friend" knew how to make the bike sound better
only when he tried to punch a whole in the baffle he knocked his home made punch right into the muffler and could not get it out
anyway
welded the muffler back on and drilled a few holes in the back plate of the muffler to allow the increased air and gas mixture to flow out as well.
I will try to post some pictures when I can.

[Easy Rider]

I cut open the filter to allow more air in


Good report.......except you left out the most important thing: Did all that actually make any improvement?

You might want to get the K&N filter that fits........at least when it comes time to replace your modified paper one.
That would probably increase your air flow a bit more.......and increasse the intake noise too. Have you ever tried it without a filter? VERY noisy from the input; almost louder than the muffler, at least for the rider.