Hey guys, I am new to the forum and could really use some advice. I recently traded for a 1996 cbr 900 rr. It has set up for a while and is needing work.

My first issue is with rebuilding the carbs. The previous owner added a K&N air filter and a Yoshimura exhaust. I am wondering about the appropriate jet sizes to use when I rebuild. The low speed jets are 40 and the high speed are after market with no markings as to their size.

This bike is fast enough, I am not trying to make it go faster just run smooth and preform well. Has anyone made these upgrades and if so how did you rejet the carbs?

Guys thanks in advance for your help. I want to get this right the first time.

Ken

 

Welcome to the CBR Forum Ken,

Nine times out of 10, a K&N filter and upgraded exhaust will not require upgraded jets.

IMHO rebuild the carbs as stock, ride the bike and see how it goes. Particularly if you are not chasing the last HP from the motor.

It will however, be a little different from the Magna

Cheers, SB

 

Welcome to the site!

It sounds to me like the PO rejetted the carbs to suit. How does it run now? Perhaps cleaning and balancing them would be a good first step. Maybe they won't need rejetting.

 

hi and welcome

 

Welcome! If you are wanting to keep the jetting, and the exhaust, I would find a GOOD tuner with a Dyno. Around $300 and they can do wonders!

 

welcome to cbrf! you should post your question in the 900rr section. they'll most likely have experience with those jets.

 

welcome, post a pic up when you can.

 

I will when I get her put back together... I have a lot of cleaning and polishing to do. She looks rough now but I see potential.

thanks for the help guys

Ken

 

Welcome to the site, man. I agree with vfrman. My first step would be to make sure the carbs are cleaned, set up, and synced. Otherwise, you may be chasing your tail so to speak.
Conrice is right, too.. head over to the 900 section and see if anyone has any other ideas.

Btw... the magna was a pretty cool bike, imo. It was a cheap sleeper that would run down a lot of cruisers.