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Exhaust Mod?

Any idea what weight of plyball should i use for akra slip on and arrow headers?It seems that the acceleration improved but top end speed was reduced.Any dyno test graph or your actual test on this same of set up.
 
Hi Again Guys,I talk with Arrow technical and they advise me to adjust the roller weights to 33g per pc so it will increase the top end but will reduce the acceleration,
now can i ask you guys what is the original weight for the stock rollers?arrow tech dont know the weight of the stock roller but instead they want me to change to 33g.
 
Are you running STOCK weights or Dr. Pulley Sliders? Sliders in the same weight as stock will increase your top end speed, due to the different geometry. With Dr. Pulleys, the variator is closed together further at rest, for lower gearing from a stop, but opens up further at high speed, making it effectively geared higher.
 
Skutorr said:
Are you running STOCK weights or Dr. Pulley Sliders? Sliders in the same weight as stock will increase your top end speed, due to the different geometry. With Dr. Pulleys, the variator is closed together further at rest, for lower gearing from a stop, but opens up further at high speed, making it effectively geared higher.
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Hi Skuttor,Yes im running on stock weights my concern is top end was reduced from 180kph before now only runs 170kph but acceleration from 0 to 120kph is very fast.
 
bill steele said:
Aside form making the exhaust note different, what benefit are you getting, You won't even notice 2 horse power up grade, and the mpg will be very small if any, seems a very expensive add on for not much benefit.
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I too wanted to change the exhaust. Probably because I came from the Harley family and change just to be changing seems to be the Harley mentality. The $750 Aprakravic seems to meet that criteria. Stock I'm getting 65 mpg by using non-ethyonal (sp?)fuel. Also can't figure out what Fuel Moto's Power Commander 5 will do for the 650's. Personally, glad to finally have a "perfect" set of 2 wheels. JMO
 
I have a 2013 C650GT. I ended up getting a 2016 C650 Sport muffler for a great deal. My question is, can I put this 2016 sport muffler on my 2013 C650GT. Do I need to remove the catylitic converter? It does look like I will need a reducer and perhaps make some mod in the length somewhere.
 

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It will be a bit of a pfaff.

The new muffler has a smaller cat underneath where the big square one use to be. Is more like a bulge in the pipe now. The old cat was also a muffler, so if you keep it and add the new muffler it might be extremely quiet, if it even fits. So, if its legal for you, you'll need to get a new header that deletes the cat, otherwise get a 2016 header with the smaller cat.

Then, the GT muffler sits at a lower angle than the sport one because of the fat arse bodywork. So you might need to modify the connecting pipe, as the muffler is a different part between Sport and GT.

Be a lot easier to just get an Akra...

Sent from my SM-T810 using Tapatalk
 
justscootin said:
I would think the warranty would be shot on the engine and the exhaust. The engine needs an exhaust with a specific back pressure which I am sure does not exist anymore more. The valve clearances and timing may also be different

The one thing that you can change is the type of oil you would use as the oil bmw specifies prevents damage to the cataletic converter.

Just my opinion and thoughts. If you do any modifications to the scooter bmw will use any excuse not to warranty the scooter and you are on your own. I say do not do any mods till your warranty is up, or at least close to the end
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There is legislation that actually protects you from this.

Of course, you lose the emissions warranty, but not anything else.
 
Hi,

I have C600 Sport (2013) with J.Costa EVO4 variator (18g) and sport air filter.
Now I've changed collector form C650 Sport.
It wasn't easy and custom modification was needed on akrapovic muffler pipe.
I was not on dyno test but for sure the sound is stunning!
 
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