`exhaust baffle, pro's and con's

[Tobyjugs]

Yesterday i took my micron exhausts off and put a pair of standard exhausts on. To my surprise they made a lot of noise, i removed the baffle only to find that they have been shortened.



Why do you think this was done?

Are there any advantages of using such a small baffle?

Would you put the short baffle or long baffle back?

[iwantalc]

I would of thought it was done for the noise,if it was quicker with short ones surely Yamaha would of made them like this,put standard long ones back in or put your microns back on..

[Gitram]

I had one like that, when i removed what remained of the baffle.. the original had broken into two pieces with the broken bit rattling around in the chamber. I had to cut a section of the pipe to remove it then weld it all back up which was a bit of a pest... hope you are luckier than me

marti 

[Tobyjugs]

The microns were removed because they are fugly and i want to sell them.
I have looked up the pipe as far as possible with a small endoscope and nothing is broken off inside luckily. They seem to be very clean compared to the exhaust pipes with the long baffles.
The bike is still set up for the Microns at the moment.

[JonW]

Sadly some pipes have the bits so lodged deep inside that you dont hear any rattles :/

[Tobyjugs]

I'm surprised by the lack of views on this topic. I thought that some of the members may have had shortened the baffles in the pipes when they were young hooligans back in the day.
I will try both types and see which one has less effect on the carburation and use that.
Cheers

[sp885]

When I bought my LC last year, I remember thinking there's no way they were this loud with standard pipes thinking back to the 250LC I had new in 81-82, when I took the baffles out one of them came out easy, the other was a real b$%@!&d of a thing to get out, but they had been cut down just like yours, I bought a new set from Norbo

[Tobyjugs]

I wonder what the reasoning for shortening them is?

[Delbert]

Dec 27, 2015 20:59:38 GMT 1 Tobyjugs said:

I'm surprised by the lack of views on this topic. I thought that some of the members may have had shortened the baffles in the pipes when they were young hooligans back in the day.
I will try both types and see which one has less effect on the carburation and use that.
Cheers

Only ever shortened the baffle in my fs1e when I was a 16 year old hooligan purely for noise , I kept getting pulled when the complete baffle was removed so I chopped it off and just had the end in !! Too old for it all now , I actually removed the baffle from my fz1 and made it longer to shut the damn thing up a bit

[Delbert]

Dec 27, 2015 21:45:55 GMT 1 Tobyjugs said:

I wonder what the reasoning for shortening them is?

I reckon it's all in the mind that more noise makes it faster !!,apparently the Japanese love the huge exhausts on modern bikes as they think the larger the exhaust the faster the bike !

[JonW]

Ive a down a set like this for my LC resto, but its still a pile of bits and nothing close to a runner, so cant comment.

[russie]

Dec 27, 2015 12:42:12 GMT 1 Gitram said:

I had one like that, when i removed what remained of the baffle.. the original had broken into two pieces with the broken bit rattling around in the chamber. I had to cut a section of the pipe to remove it then weld it all back up which was a bit of a pest... hope you are luckier than me

marti 

+1 with experience of this problem. Are you sure the rest of them isn't in there? I tried welding mine but found trying to weld the perforated tube part combined with my limited ability resulted in something that looked like a baffle with a Ferrero-Rocher half way along it! Threw it to f**k and got some of Norbo.

[Tobyjugs]

Dec 28, 2015 15:34:05 GMT 1 russie said:

Dec 27, 2015 12:42:12 GMT 1 Gitram said:

I had one like that, when i removed what remained of the baffle.. the original had broken into two pieces with the broken bit rattling around in the chamber. I had to cut a section of the pipe to remove it then weld it all back up which was a bit of a pest... hope you are luckier than me

marti 

+1 with experience of this problem. Are you sure the rest of them isn't in there? I tried welding mine but found trying to weld the perforated tube part combined with my limited ability resulted in something that looked like a baffle with a Ferrero-Rocher half way along it! Threw it to f**k and got some of Norbo.

Thanks for the concern but i have inspected them both with an endoscope,
I have been riding around testing both sets of baffles today and i can feel no difference with the bum dyno but the Short baffles gave a slightly weaker colour on the plug so i will keep the long baffles in the pipes.
I shall also take the wadding off which is wrapped around the perferrated end.
I must admit i do like the sound the shortened baffles make they sound like Higgspeeds.

[Tobyjugs]

Fitted my ignitech today and while it was on the dyno i measured the normal baffles and the shortened baffles to see what the difference was.



The green line represents the normal baffles

[Deleted]

Now that's interesting, I too have shortened baffles on my 31K, they were like that when I bought it, I lost one (it rattled out) and had two made up by the next door neighbour out of stainless tube, not for performance but to quieten the darn thing down.

The dyno result seems to say the short ones give more power down low then taper off just before 8000rpm the standard damper has less power down low but more on the top end and more HP overall

Perhaps Mr Yamaha new what he was doing after all

Who said more noise = more power, just goes to show we were all wrong all those years ago

Really good comparison Tobyjugs

[Tobyjugs]

Normal baffles give 1.8 more pk or short baffles gives 1.5 nm more torque. In the real world i think you have to know your bike very well to feel the difference 

[Deleted]

Yep I agree totally

Your results are still interesting all the same

[unrealedd]

Back in the day I used to cut/shorten the end cans on the dirt bikes, seemed to give more low down grunt allowing more control for wheelies and slightly louder. Seems that dyno graph confirms this beautifully.
This only worked on 2 stroke diesels are a differs matter entirely.
This also worked better on stock engines tuned engines behave very differently and you can wreck the power of a tuned motor shortening or messing with the pipes.

[copper99]

I was reading this old magazine last night which had an article on tuning LCs, the author had tried all types of modifications on standard pipes, inc shortening the baffles, he discovered un-tampered worked best too..

[JonW]

Thanks for the dyno testing, interesting stuff!

Copper, worth a scan?

[JonW]

Thinking about this... the conventional wisdom is for LC pipes is that you dont need any packing around the end of these baffles as it made hardly any difference to the noise, that says to me that the main noise reduction was all done in the longer tube with the deflecting plates, ie the bit that breaks off LOL. I assume that also must have generated some back pressure helping the engine breathe more efficiently at higher revs. This makes me wonder... On a set of spannies with seperate, removable alloy cans that if i gutted the end cans and then fitted one of the OEM baffles, or some made some sorter ones like them, might they be quieter than the straight through perforated tube and wadding Ive got now and also increase top end? hmm... Has anyone ever tried that?

[copper99]

Feb 28, 2016 23:10:33 GMT 1 JonW said:

Thanks for the dyno testing, interesting stuff!

Copper, worth a scan?

Taken me a little while but here it is mate.

[JonW]

Cool, Thanks Copper!

[mikeb]

I figured that the baffle is actually the stinger pipe, so I made some full length tubes so the internal end sat where it should but the pipe is straight through. It was a little louder than standard but had more of a "crack", sounded more like chambers which is what I was after. Seemed to run fine.

[Norbo]

They don't look like they have been cut but rather broke . id stick some full length ones back in .