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Discussion Starter #1
Hello to all,
so i just did a stage 2 debaffle on my 12'vn900classic. my hd body at work warned me that i might have an issue with warped valves if i debaffle my exhaust. now, everything ive read so far hasnt said much about this after people have done this mod. just want to make sure im not causing potential issues with my bike. any and all info is helpful. thanks
 

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Absolutely not.

The 'debaffled pipes cause warped valves' is a classic example of a small amount of truth warped into something else. It's because people don't understand the ROOT CAUSE of the issues.

Warped valves can be caused by cold air being sucked back into the exhaust and hitting hot valves. The stock 900 exhaust is way too long to ever do that, besides, it has a cat converter still in there, so even a full debaffle isn't 'straight pipes'

It's one of those causes of basic observation without asking the important 'why' question. Billy Bob the Racecar Builder noticed his open-header racecars burn valves. He knows open headers provides more flow. So he determines, straight pipes or high-flowing exhaust will burn valves. The real reason was because A) he was racing the darn thing B) likely the mixtures weren't great and C) cold air could have been sucked back up through those open headers hitting hot valves, especially on shutdown, causing them to be warped. That's why engines where longevity is important (like NASCAR engines that have to go several hundred miles) you'll find straight pipe exhaust, but an engine that only goes 1/4 mile between rebuilds, like a top fuel dragster, will have short straight pipes out of each exhaust port.

I always say it, so, I'll say it here. Go for the full debaffle! It's not much louder but it's much much deeper and throatier! :p

The only issue you MAY have is running a little lean due to less backpressure (thus more air can get into the cylinder). However, the presence of the cat converter generally makes this a non-issue, as it probably causes the most restriction in the entire system. However, without a fuel process, I would NOT run any aftermarket air-intakes with your debaffled exhaust.

-John
 

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Discussion Starter #3
Thanks for the info romans. Being that im a new rider, i dont have the knowledge to debunk such claims.ive learned soooo much from this forum its amazings. Im sure if people were ruining their bikes from debaffling there would be tons of post stating so. i am considering a full debaffle, as of know i have 4holes drilled in each pipe. sounds better than stock but still looking for a deeper throatier sound without the $500 set of aftermarket pipes.
 

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Thanks for the info romans. Being that im a new rider, i dont have the knowledge to debunk such claims.ive learned soooo much from this forum its amazings. Im sure if people were ruining their bikes from debaffling there would be tons of post stating so. i am considering a full debaffle, as of know i have 4holes drilled in each pipe. sounds better than stock but still looking for a deeper throatier sound without the $500 set of aftermarket pipes.
Then the full debaffle is the way to go! Do it and never look back :D
 

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AA fuel dragsters have short exhaust stacks because they are supercharged and exhaust tuning becomes almost irrelevant.

Valve damage , among other things, can occur when exhaust modifications are made and follow-up tuning is not checked/performed.

Blanket statements such as "if you do X, you do not have to do Y", etc. can be a bad road to follow. Every engine/situation is different and the tuning considerations must be tailored to each individual application.
 

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Then the full debaffle is the way to go! Do it and never look back :D
It's been 18 months since I performed a full debaffle, and have not looked back. Love the deeper sound. Even cruising down the super slab has a nice tone.
 

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Discussion Starter #7
Havent went full debaffle yet bosco, but did take it up to 6 hole per pipe. notice the difference in sound on the super slab on my way home. I'll probably go to a full debaffle in the next month or so. i noticed you live in corona bosco, is there anything to worry about when i do my yearly inspection with the dmv?
 

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Fully debaffled mine and never had a problem.

Sent from my SAMSUNG-SGH-I727 using Motorcycle.com Free App
 

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Full de baffle here also

Fully de baffled mine 6 months ago and ridden 7ooo miles through a British winter. Does occasionally pop, but sounds so good. Just got to get round to fitting some collars over the ends of the exhausts, as I de baffled mine by sawing the ends of the pipes to remove the "slash cut look"! Just a shame the rest of the bike is suffering from a severe winters riding in the UK. Lots of flaking paint and rust coming through in places. Going to need some TLC in springtime.....Hey ho I bought it to ride, not polish.:)
 
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