rosszx9r Posted August 17, 2008 Share Posted August 17, 2008 i've got an odd problem with my zx9r (b1) engine. on a balanced throttle, the engine loads and unloads continuously.i can hear it as i ride along. there is a distinct noise when the engine is just under load and another when it is just off load. i can hear it loading unloading when holding the throttle steady and riding along a flat road. i can also feel the bike surging slightly as the noise changes.this happens mainly at low revs and gets better if i drop a gear or two.i balanced the carbs which did improve things and i've also fitted new secondary air injection valves incase this was affecting low speed running.the bike runs fine apart from this and doesn't burn any oil.any suggestion? Quote Link to comment Share on other sites More sharing options...
Stu Posted August 17, 2008 Share Posted August 17, 2008 try a new air filter and give the carbs a good clean out also check chain tension Quote Link to comment Share on other sites More sharing options...
rosszx9r Posted August 17, 2008 Author Share Posted August 17, 2008 thanks for that. i already changed the air filter and the plugs before i balanced the carbs. i drained the carbs and washed them through with carb cleaning spray but didn't strip them down as them seemed in pretty good nick and the bike idles smoothly and pulls cleanly (now the cards are balanced )chain tension is fine too. this one's got me really stumped! Quote Link to comment Share on other sites More sharing options...
rennie Posted August 17, 2008 Share Posted August 17, 2008 you sure you're not gripping too hard?really? i did it when i first had the blade Quote Link to comment Share on other sites More sharing options...
rollazuki Posted August 17, 2008 Share Posted August 17, 2008 known issue, can be two things, carb icing(even in nice weather, not just winter), and wind shear across the ram air.If its bad in side winds, its wind shear, if its all the time, Id try a fuel additive, or super unleaded for a tankfull. see if it improves. Cheap supermarket fuel can be a beggar for it.Just one thing to check, ensure the ramair pressure pipe(the little black ones that plumb into the raimair ducts then(I think) possibly T together, and head back to the carbs to pressurise the cv chambers, are fully plumbed in, clipped on, and no leaks. If they are left off, the carbs refuse to work at speed, but if split slightly, they can lead to all manner of hunting and surging at slight speeds. Quote Link to comment Share on other sites More sharing options...
rosszx9r Posted August 17, 2008 Author Share Posted August 17, 2008 excellent, thanks. i'll give it a go... Quote Link to comment Share on other sites More sharing options...
ade38 Posted August 18, 2008 Share Posted August 18, 2008 i got similar issues with mine such as low revs i'm like a kangaroo but many kawasaki experts have told me it is a problem they all have but cleaning the carbs helps aswell as balancing. Another problem they've got is the cams wear down very quickly to soft metal, espeacially if you do a lot of wheelies if so tell no one and get rid.(unless your loaded) But i'm only going by what i've been told, i hope that helps? Also whats the mileage as general wear and tear plays a part Quote Link to comment Share on other sites More sharing options...
rosszx9r Posted August 18, 2008 Author Share Posted August 18, 2008 it's done 42k but i've had the rocker cover off and cams look in good nick, only normal rub marks you'd expect to see.i'll give the petrol addative a try tomorrow and see how it goes. failing that, it looks like a full carb strip down will be needed.... oh joy when i balanced the carbs, they were well out to begin with and i got them as close as i could. they weren't perfect but had about 5mm difference between each cylender (carbtune vacum gauges) acording to the the carbtune manual this is fine. Quote Link to comment Share on other sites More sharing options...
ade38 Posted August 19, 2008 Share Posted August 19, 2008 has it got an aftermarket exhaust? Quote Link to comment Share on other sites More sharing options...
rosszx9r Posted August 19, 2008 Author Share Posted August 19, 2008 no, it's all bog standard. the bloke i bought it off had an aftermarket (don't know what kind) but put the origonal back on for the MOT and sale. i did think he may of had it rejetted. didn't think to ask at the time! Quote Link to comment Share on other sites More sharing options...
ade38 Posted August 19, 2008 Share Posted August 19, 2008 not sure then as i put the standard on mine and it makes a big difference.(but i cant have a quiete bike) The only thing would be give it to a dealer but that would cost millions! Quote Link to comment Share on other sites More sharing options...
rosszx9r Posted August 19, 2008 Author Share Posted August 19, 2008 give it to a dealer..... what and give up!..... never..... we shall fight on the beaches, we shall fight on the landing grounds, we shall fight in the fields and in the streets, we shall fight in the hills; we shall never surrender..... to dealer at any rate Quote Link to comment Share on other sites More sharing options...
rosszx9r Posted August 21, 2008 Author Share Posted August 21, 2008 Id try a fuel additive, or super unleaded for a tankfull. see if it improves. well, 1 tank of super unleaded, half a bottle of redex, a full bore blast down the nearby motorway for a few miles and, well..... it's a little bit better. it's livable but it will still iritate me.i think all this proves is i need a full carb strip down and overhaul. just need to find the time to do it thanks for giving it some thought though... Quote Link to comment Share on other sites More sharing options...
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