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General Category => Modifications => Topic started by: Tor-King on April 06, 2017, 10:03:50 PM

Title: Supertrapp tuning disc question!
Post by: Tor-King on April 06, 2017, 10:03:50 PM
Hi all.

I have a 2 into 2 Supertrapp exhaust on my 3CV.  I do not require it to be overly tuned for high end performance/horsepower but need a starting point as to the number of tuning discs I require.  Currently there are 5 discs on each side...  It is not overly loud but would like to know if this number is creating too much back pressure or rich condition?? I acquired the bike last year and this is how it was set up. Can anyone who has this exhaust give me some guidance?

Thanks!
Dean
Title: Re: Supertrapp tuning disc question!
Post by: Tor-King on April 06, 2017, 10:07:54 PM
Oh, and the jetting is 110 mains and 42.5 pilots with 2 1/2 turns out on the mixture screws...  The airbox is factory.
Thanks,
Dean
Title: Re: Supertrapp tuning disc question!
Post by: FJmonkey on April 06, 2017, 11:38:25 PM
What do the plugs look like?
Title: Re: Supertrapp tuning disc question!
Post by: FJ1100mjk on April 07, 2017, 04:33:04 AM
Quote from: Tor-King on April 06, 2017, 10:03:50 PM
Hi all.

I have a 2 into 2 Supertrapp exhaust on my 3CV.  I do not require it to be overly tuned for high end performance/horsepower but need a starting point as to the number of tuning discs I require.  Currently there are 5 discs on each side...  It is not overly loud but would like to know if this number is creating too much back pressure or rich condition?? I acquired the bike last year and this is how it was set up. Can anyone who has this exhaust give me some guidance?

Thanks!
Dean

From another source, an '86 with a similar system as yours:

I have the stock airbox with a Yoshimura exhaust system and I run:
#42.5 pilot jets
#117.5 main jets
Stock needle shimmed .035"

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I have an '87, that has a 4-1 SuperTrapp on it with six or seven discs on its can. It has size 40 pilot jets, 112.5 standard mains, and standard air jets. I can't recall how many turns out the pilot air screws are. It has always run fine, and I have put some good miles on it.
Title: Re: Supertrapp tuning disc question!
Post by: yamaha fj rider on April 08, 2017, 03:02:42 AM
I had a Supertrap 4 into 1, it had 12 disks. I used a Factory Pro jet kit.

Kurt