My ZZR 400 has no power. I've replaced the jets .

Hi there and welcome to fixya,

I can share with your sentiment there. Here's are some of my ideas, you'll need to be patient enough though.

the jets you used, is it the stock replacement or a bigger one? I would recommend using the stock jets to eliminate the possibility of it being the cause. Tune your engine using a timing light, synchronize the carburetors so each intake manifold receives the same amount of fuel on throttle. Drain the fuel form the carb reservoir (or clean the whole carbs including the jets). Adjust the air-fuel mix to standard or 2.5 -3.5 turns out. Check for hose dents and check for proper plug firing.

Make sure cylinder compression is also good otherwise you'll suffer power loss on peak RPMs at high speeds.

The above process should eliminate any possibility with regards engine idling and poor idling.

To answer your question regarding valve clearance you'll need to download the manual to assist you on dissassembly. You'll need to remove the top cover on the engine and use a feeler gauge for adjustments. I'm not sure how to find the TopDeadCenter of this particular bike but the manual should.


Hope this in any helps you out,
levibit