# Exhaust Mod Sound Clips



## whoolieshop

did the stock muffler mod on my 650 h1 today here's a before and after of the sound.


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## Polaris425

Nice improvement!! Did you happen to take any pics while it was open?


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## whoolieshop

I sure did we used a chop saw with a steel cutting blade in it to cut the end of the muffler off and the output tube.



once the end was cut off, we torched the output tube off even with the other pipes then blew a few holes in the baffle plate. This just opened it up and kept the exhaust from having to travel all the way around the inside before coming out the output tube.


Most people use a 1/2" drill to punch the holes but the torch was already lit and faster lol.


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## Polaris425

lol. Nice job! Glad to see someone doing it on something other than a brute. I always get questions about it. "Does this work on other brands?" I dunno, crack it open and look inside!! haha at least someone finnaly did! :bigok:


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## whoolieshop

Thanks, i made a video with just the audio mostly and trimmed out most of me talking, the before and after are back to back with none of me blabbing in between


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## greenkitty7

my favorite wrench is the yellow headed one as well... so versitile


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## Mr.bruteforce

hey i got a 2010 750 brute force that is fuel injected and i want to drill out the baffle and open up the turbine would i have to re map it where its fuel injected


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## brute for mud

good job sounds sweet


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## primetime1267

Great job bro!!! Sounds a lot better with a tad more throttle response even.


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## Polaris425

Mr.bruteforce said:


> hey i got a 2010 750 brute force that is fuel injected and i want to drill out the baffle and open up the turbine would i have to re map it where its fuel injected


you shouldnt have to... look for this same thread in the kawi how-to section... lot's of info in it.


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## greenkitty7

AC people have been doing this for a long time now... but this is a great write up pond! i always look forward to reading your stuff. I know how to do it all but I dont have the ability to put it into words. Great job again.


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## JGBigBear

i got the 700 h1 efi when i do that and snorkel it am i going to have to mess with the efi?


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## greenkitty7

You may need to get a programmer. The 700efi ia tuned pretty rich from the factory all you can do is try it and if it runs rough, go ahead and get a programmer


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## whoolieshop

Any time you mess with amount of air entering or leaving your engine you are messing with the air/fuel ratio. Too much air and it will run lean causing excessive heat and loss of power, to much fuel and it'll run rich fouling spark plugs and causing bogging. 

Your EFI system can account for some variations but imo the exhaust mod and snorkels will be too much of a change for it to compensate on its own. As a general rule the better your engine can breath the more power it can potentially make but you have to add in fuel to keep the air/fuel mixture right.


Snorkeling is kind of a gray area, since people often take different routes, use different sized piping a snorkel can end up more restrictive than the factory setup thus richening the mixture, that coupled with the exhaust mod can bring it back to normal. However; if your snorkels flow better than stock then you add in the exhaust mod you could end up a little lean or dangerously lean.

Go ahead and pick up a programmer that way you know it's right, if you get a power commander 5 plan on buying the auto tune module, the auto tune module will custom tailor the map for YOUR bike as you ride, not a pre-set map that someone made on a dyno in a shop.


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## greenkitty7

:agreed: too lean can even cause you to burn up the rings. or a hole in the piston. It would probably be fine with the snorkel bc, like stated above, those 700efis have a pretty rich tune from the factory, but with the exhaust mod it will probably be getting too much air flow.


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## skeeter_nash84

What about doing this exhaust mod on the 650 v2 that is not fuel injected I am snorkeling it now. Do you think the snorkel and exhaust mod would make my bike to lean and if it would how would I go about making it a bit more rich for these mods?


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## whoolieshop

I would bet you're gonna get lean doing both of them. Any time you adjust the airflow going in/out of the engine you can run into air fuel mixture issues. 

Jetting isn't all that hard to do and I love my modded exhaust. On the V2's you need to have the rear carb jetted a little richer than the front I do believe. Pick up one of those dynojet kits and you should have everything you need to compensate for the increased airflow.


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## skeeter_nash84

Will the dynojet kit for my bike include jets for both carbs and does it come with pretty good instructions?


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## whoolieshop

Yes it comes with both jets for the V2 and it comes with instructions 
you'll have to take your carbs out to change the jets though might want to download a repair manual to assist you in teardown / re-assembly.

The carbs themselves aren't very complicated.


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## skeeter_nash84

Yeah I already purchased the repair manual in .pdf form on a disc from ebay and made my own paperback copy for projects like this


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