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R1 2008 motor issue

739 Views 3 Replies 3 Participants Last post by  Chop
Hello, recently i had my bike repaired out of a serious problem.

After loosing lots of power, i took it to the service and while checking the compression on the cylinders, it was found some major loss of compression of two of em.

Long story short, only some sort of super mild "licking" was executed on the inside of the cylinders and kept pistons but swapped to new piston-rings along with valves and etc.

The mechanic claims its due to bad fuelling (to be exact - TOO MUCH FUEL) and blaims the PC3 for that.

My PC3 was using a ready map from Akrapovic for open system (im using Baffles + Leo Y pipe).

Now i have to brake the bike again and he advices me against using the PC3.

What should i do? Feels like the Mechanic is selling me shit for candy.
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Get a 2nd opinion. Open system with baffles need fuel and air adjustments. I'm no expert but I think the stock system can't compensate for the change in exhaust. I had mine dyno tuned and never had a problem so hopefully someone that knows more than I do can chime in.

Good Luck!
My PC3 was using a ready map from Akrapovic for open system (im using Baffles + Leo Y pipe).
Do you mean you used a map downloaded from the dynojet web site? My understanding is these maps are generally a little rich. I'd suspect deliberately to avoid liability issues if bikes started detonating due to lean mixtures.

Only way to have it right for your bike is a custom dyno tune from a reputable tuner IMO. If I had mine over again I'd get it flashed I think.
Thanx both of you for your replies but im still in the blue.

Since i cant afford a dyno, what should i do? Go back to stock? Keep Y pipe and Baffles and run without PC3?
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