Hello all,

I am new to the forms because I just bought my first bike! she is a 89 cbr 600 w/36k on the odo. She runs great for the most part, but what could be causing the bouncing rpms at idle? she generally sits at 1k, and will rise to 1100k, and fall back down in intervals of 2 seconds or so. I asked this in my generation specific side, and I got a response that I should adjust my idle screw to raise the Idle rpms, however it may not fix the bouncing.

Any idea's? thanks in advance guys! (and Gals)

 

If it runs fine in the higher rev range then synchronize the carbs. If you have even a small talent for working on mechanical stuff then I'd suggest buying the service manual (or download it) and get the carb synch tool and do it yourself. Raising the idle to 1150 - 1200 rpms might help also.

Oh, and welcome to the board! Post up a gallery of pics when you get a chance.

 

Hi there!

thanks for your help onthis one - I am very mechanical, I just know absolutely nothing about bikes! I already looked into getting the FSM for the bike, but Honda wanted $35. what a rip! (lol) Ihave been keeping an eye on Ebay, but maybe I will search the net...

Carb sync tool you say? Is this what I need?

http://cgi.ebay.com/ebaymotors/CARB-...spagenameZWDVW

the top of the carbs are very easy to get to, but I am not sure where the adjustment screws are that they speak of. I really need a manual!

I will be sure to post up some pictures in the gallery! I took quite a few... and some when I dismanteled it as well to swap out the fuel pump. I'll post some up when I get home from work.

 

Here's a picture of what I'm talking about. There are some that have dial gauges instead of the tube but they cost a bit more.

 

Oh, almost forgot ... the adjusting screws are located between the carbs on the linkage. One carb is not adjustable -- you adjust the other carbs to it.

 

Awesome, thanks again bud! I will watch online and see if I can pick one up used.

BTW, have you really gone 228mph??

 

Not on my 1kRR -- that was on my old turbo busa

It was one bad machine[sm=badbadbad.gif]

 

Agreed - the CarbTune is what you want. There are less expensive synchronizine tools out there that use mercury as an indicator, but if you can spend the money get the CarbTune, which I think uses metal rods, and avoid playing around with mercury. If the idle problem isn't solved by synching the carbs you will most likely have to take the carbs apart and clean them. Good choice for a first bike, by the way and welcome to the sport.