Yoshi 4-1 R-77 Issue

[Macmotortrimmer]

Hi Just had my 08 busa dynoed was putting out 167hp @ rw stock trim

He installed the full system, and ran it up to see and it lost 7hp straight off the bat.

He has been trying to tune it with out much luck when he getting up to the 80% throttle range he is having to remove up to 40% gas.

He has done some measuring and found the inside size of stock pipes if 38mm, where the yoshi can is 33mm, and he said often dual cans run smaller than stock, due to being more free flowing, but as its is now it restricing the bike

He thinks that might have been sent the end can for a dual system (not to sure if any difference)

Anyone got any ideas.  What could be the issue?

 

[GPW]

Interesting......

 

[TA_GunSurgeon]

I would call yosh customer service. I had a problem with a airleak from the lower end of my canister and from 2 of the rivets on my R-77. This caused the sealant to leak out and bake onto the pipe. I called Yosh sent them a few pics there sending me a new exhaust at no charge and said I can keep the old one. They did say it would be 3-4 weeks because of back order, but there customer service was great !

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[NumbNuts]

Mine went from 168.23 to 180.74, tuned with a PC3. What did he do with the oxygen sensor? The guy who mapped mine said he checked around and was told it was best to disconnect it. He just put a short bolt in the hole in the exhaust. Runs great and no error messages.

It seems to me the wrong can wouldn't fit on the exhaust system...

 

[GPW]

PM -->

1289974[/ATTACH] PM]
Mine went from 168.23 to 180.74, tuned with a PC3.  What did he do with the oxygen sensor?  The guy who mapped mine said he checked around and was told it was best to disconnect it.  He just put a short bolt in the hole in the exhaust.  Runs great and no error messages.

 It seems to me the wrong can wouldn't fit on the exhaust system...

Thats more like it.

 

[Macmotortrimmer]

Mine went from 168.23 to 180.74, tuned with a PC3. What did he do with the oxygen sensor? The guy who mapped mine said he checked around and was told it was best to disconnect it. He just put a short bolt in the hole in the exhaust. Runs great and no error messages.

It seems to me the wrong can wouldn't fit on the exhaust system...

Oxygen sensor as been unpluged and then bolt put in hole.

He has got it up 180hp now, by removing the baffle out of the can. got a few more tweaks he wants next week.