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Is it my imagination or does the bike lose engine braking compression with the standard exhaust mod ? ( gutting )

During the initial 600 miles i was very wary of changing down to second or first for fear of locking up the rear. In fact i wondered if i would ever need to change brake pads as the bike slowed its self down for a stop so effectively by just closing the throttle.

Then i serviced it and gutted the pipes.
Now, either im just used to the bike and can do these downchanges from quite a fair speed or the exhaust gutting has lowered compression somehow and the bike runs on - off throttle - easier and is less prone to locking up the rear under downshifting.

I would prefer it to be my imagination as besides the nicer sound - im trying to justify gutting my exhaust with lingering concerns about leaning it out, losing compression, and possible low down torque performance loss due to lower backpressure. Im somewhat pacified with the idea that the SET controls the backpressure regardless of the state of the muffler.

Any perceptions out there ?

Im a bit of a sissy when it comes to mods as my mind will not let things be when i have any doubts. ( i have an unopened JSD-3M sitting on my shelf for just this reason and we even have unleaded 95 at most stations here )

As a side note, a buddy on a busa on the weekend behind me remarked that my pipes seem to shake around a lot under acceleration. Could this be the cause or the effect of the harsh hard rear end vibration ( feels like you are riding on a bare rear rim ) that comes on when cracking the throttle from 3500 to 4500 and beyond and lets up immediately you close the throttle ? ( another idea in the face of "the nature of the beast" arguments i have read here )

skin.
 

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ppridgen1 said:
it's your immagination running wild . You still have the set valve that closes with the computer and wouldn't let you lose back pressure like your thinking! your just getting more used to the bike ! Relax bro,it'll be fine
I would agree. I haven't modified my pipes they are still stock and the more I have gotten used to the bike, I have noticed the same ease in downshifting. It's normal, you are just getting used to the bike! :bigthumbsup:
 

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skindiver said:
As a side note, a buddy on a busa on the weekend behind me remarked that my pipes seem to shake around a lot under acceleration. Could this be the cause or the effect of the harsh hard rear end vibration ( feels like you are riding on a bare rear rim ) that comes on when cracking the throttle from 3500 to 4500 and beyond and lets up immediately you close the throttle ? ( another idea in the face of "the nature of the beast" arguments i have read here )
skin.
Check to make sure one of the exhaust mounting bolts hasn't fallen out: http://www.m109riders.com/forum/index.php?topic=3615.msg46562#msg46562

I've done a little modding to my exhaust and didn't notice any difference in anything except a throatier sound :doorag:

As far as the overall throbbing under acceleration @ 3K to 4K RPM... just enjoy it :D
 
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