[benzif]

hello from italy! I would like to share my eperiences on my tuning done on my CBR 900RR '97. I love this bike (few years ago I sold it, bought a R1 and few weeks later sold R1 and re-bought my RR...).
here we go to facts: I have akrapovic 4x1 w/o mid pipe compensator (not 4-2-1); dynojet stage 1 #118 (#122 suggested but too fat) 4° groove from top as suggested, K&N filter, +4° advance timing. Engine runs quite well and performance gain is great vs stock. What I want to improve?? Well when engine is in 6th gear idle and quickly WOT then the torque is showing some holes up to 3500 rpm. This is perceived in all gears at low rpm. I have been trying all DJ setting (jet# and needle position) but does not change. Now best perceived setting is #118 and 4° groove from top. The A/F shows it is very rich where torque shows its valley.
Obviously the DJ kit has been fitted with max care and skill, following the tech instructions.

Q1: Can I make some improvement by lowering the pilot jet (@40) ? Obviously this is not provided in the DJ kit. The DJ instruction sheet are quite poor (i.e do not show how the single components like jets, needle position affecting the torque trend at WOT).

Q2: can I get some benefit fitting some 4-2-1 aftermarket exhaust or just by adding mid compensator pipes 1 to 2 and 3 to 4?
(bike has "only" 40k miles so the answer "change it" is not accepted!

[rokitt51]

Originally Posted by benzif

hello from italy! I would like to share my eperiences on my tuning done on my CBR 900RR '97. I love this bike (few years ago I sold it, bought a R1 and few weeks later sold R1 and re-bought my RR...).
here we go to facts: I have akrapovic 4x1 w/o mid pipe compensator (not 4-2-1); dynojet stage 1 #118 (#122 suggested but too fat) 4° groove from top as suggested, K&N filter, +4° advance timing. Engine runs quite well and performance gain is great vs stock. What I want to improve?? Well when engine is in 6th gear idle and quickly WOT then the torque is showing some holes up to 3500 rpm. This is perceived in all gears at low rpm. I have been trying all DJ setting (jet# and needle position) but does not change. Now best perceived setting is #118 and 4° groove from top. The A/F shows it is very rich where torque shows its valley.
Obviously the DJ kit has been fitted with max care and skill, following the tech instructions.

Q1: Can I make some improvement by lowering the pilot jet (@40) ? Obviously this is not provided in the DJ kit. The DJ instruction sheet are quite poor (i.e do not show how the single components like jets, needle position affecting the torque trend at WOT).

Q2: can I get some benefit fitting some 4-2-1 aftermarket exhaust or just by adding mid compensator pipes 1 to 2 and 3 to 4?
(bike has "only" 40k miles so the answer "change it" is not accepted!

to the site. I dont have any experience with ur bike, but someone is gonna be able to help you out.

[Bill-S-Preston]

What was wrong with the R1? I have a 97 blade and am thinking about getting an R1.The blade is just to old,built like a cadillac without the comfort,front end seems to flex too much,bad breaks,16 inch wheel,the list goes on and on.

[stoney0422]

sorry i cant help i took mine to the shop to get it tuned i dont have the know how or ability/patience to deal with that stuff... but where at in italy i lived near pordenone for 2 years

[nedro]

I don't think you understand how a high HP engine works as opposed to a high torque engine. I would NEVER even consider opening up the throttle in 6th gear under 4K RPMs. I think you are chasing dragons...