Gregorious77 Posted February 16, 2010 Report Share Posted February 16, 2010 Anyone help me out here. I am 99% sure I have a bad rod bearing on my 6R, I have a knock under load and can feel a definate knocking through the bars and pegs, this happens both on power and under deceleration through 4-5K revs. Does anyone know is there any way of checking the big ends without splitting the case? It looks like you cant just whip the sump off as there is a plate or something in between. Where would be a good place to buy parts? looks like £140 for a full gasket set alone but I dont need all of them. I will check and adjust the valve clearances while I am at it so will need a cam cover gasket. I am confident I can do the job, its just a pain in the ass I have to take the engine out and split the cases to do it meaning cycling to work while its in bits. anything else worth doing while I am there? Bike has only got 11000 on the clocks and is in very good condition eccept the knock. anyone have an idea on cost of bits for this job? I am guessing around £200 or so, I have seen a crank with rods on ebay for £60 so that may also be an option. Link to comment Share on other sites More sharing options...
Hendo Posted February 16, 2010 Report Share Posted February 16, 2010 Sorry I can be no help, but what makes you think it could be the big end bearings? At 11,000miles? On a jap bike? Only curious like. Andy Link to comment Share on other sites More sharing options...
Gregorious77 Posted February 16, 2010 Author Report Share Posted February 16, 2010 Because there is a knock and a notchy vibe @ 4-5K under load. I agree it sounds unlikely at 11K but I cant think what else it might be unless its a gear? maybe on the cltch drive? Link to comment Share on other sites More sharing options...
cagimaha Posted February 16, 2010 Report Share Posted February 16, 2010 Seeing as the cost of even just checking the big ends is so high I'd make sure it wasn't anything else first. It could be the clutch hub loose. Also, and I know this sounds like it definitely isn't serious enough to cause the symptoms you describe but just check the carbs/throttle bodies are synched up. It can cause all manner of problems such as juddering and such like. The carbs/throttle bodies you could check yourself for nothing and the clutch you could check for at the most a clutch gasket and a change of oil. Link to comment Share on other sites More sharing options...
Gregorious77 Posted February 16, 2010 Author Report Share Posted February 16, 2010 Carbs are all balanced, I have made sure of that bit, it was my first stop. Gonna do a compression test next to check the top end is sound. Link to comment Share on other sites More sharing options...
tootall Posted February 16, 2010 Report Share Posted February 16, 2010 Cradley Kawasaki for parts. However as said above it'd be well worth eliminating all other possibilties before going for a strip down. Clutch or generator being favorite. edit: Does this only happen under load, i.e when riding/in gear or can you recreate this at a standstill just revving up? Link to comment Share on other sites More sharing options...
Gregorious77 Posted February 16, 2010 Author Report Share Posted February 16, 2010 Can just about hear it in neutral reving gently not as bad though, but will do it in gear slipping the clutch to pull away but not moving IYKWIM so I dont belive it is gearbox. Will whip off the geni cover and clutch case at the weekend if I can get some gaskets in time and if my wife doesnt go into labour!! Link to comment Share on other sites More sharing options...
Gregorious77 Posted February 16, 2010 Author Report Share Posted February 16, 2010 gaskets ordered. Is it worth me checking the oil pressure? will a bad big end show up a loss in pressure? Link to comment Share on other sites More sharing options...
Gregorious77 Posted February 16, 2010 Author Report Share Posted February 16, 2010 Thats what I thought! Link to comment Share on other sites More sharing options...
nigel.ted Posted February 17, 2010 Report Share Posted February 17, 2010 Buy a complete motor of a breaker or T'bay if it helps i have a 99 zx6 as well if you need owt but i am not takin the motor apart nigel Link to comment Share on other sites More sharing options...
Mr.Pigdog Posted February 17, 2010 Report Share Posted February 17, 2010 You wont need a new cam cover gasket just because youre checking the valve clearances--theyre quite reusable unless a butcher hs been at it--the engines are very strong-you've checked the camchain tensioner?maybe manually click it out one notch? Link to comment Share on other sites More sharing options...
Gregorious77 Posted February 17, 2010 Author Report Share Posted February 17, 2010 I have just done the camchain tentioner tonight but then I went upstairs to get a funnel to run it with the tank off and fell down the stairs and dislocated my shoulder!!! oops 3 hrs in a&e and it is now back in. not sure if I am goint to be able to swing a spanner to good tomorrow when the drugs have worn off, last time I did this I was out for 8 weeks. Link to comment Share on other sites More sharing options...
ronenige Posted February 18, 2010 Report Share Posted February 18, 2010 some of them motors had a bit of piston slap even from new , a bit like an early blade but not as bad , unfortunately only proper way to tell is looking at the pistons , having said that , i've never heard of one giving any problems , does the noise go away at higher rev's ? Link to comment Share on other sites More sharing options...
Gregorious77 Posted February 18, 2010 Author Report Share Posted February 18, 2010 at higher revs the noise is still there but it is drowned out by the induction and can noise. It seems worse on light throttle, like mid corner when you are adding only a little throttle. cant hear it on tickover but there is some valvetrain noise. I was going to get my screwdriver/ear over the engine to see if I could pin point the sounde but really it needs to be under load so this is a bit impossible. Link to comment Share on other sites More sharing options...
Marb Posted February 18, 2010 Report Share Posted February 18, 2010 If it is the bigends. Remove the sump and you should have tiny copper flakes in your oil. Looks like a metallic paint. Link to comment Share on other sites More sharing options...
Gregorious77 Posted March 6, 2010 Author Report Share Posted March 6, 2010 Update on this, My shoulder is feeling much better and I have been without the sling for about a week so I had a good look over the bike. I used a mechanics stethoscope and listened all over the engine on tickover and while reving gently. My verdict is it sounds to me like piston slap as each cylinder had a diesel type knock to it and there are no other nasty noises anywhere else on the engine, only the cylinders have the sound. Still not done a compression test though. Is piston slap a major problem or is it just something I will have to ignore and live with? Link to comment Share on other sites More sharing options...
Harry Muff Posted March 6, 2010 Report Share Posted March 6, 2010 Does it happen all the time? If so, then just give it to a garage to have a ride round on. Putting it on a dyno is another way of checking it while it's under load. Link to comment Share on other sites More sharing options...
ronenige Posted March 6, 2010 Report Share Posted March 6, 2010 Is piston slap a major problem or is it just something I will have to ignore and live with? run it for a bit , if it doesn't get any worse ignore it , these motors are designed to be revved so rev the bugger a bit more Link to comment Share on other sites More sharing options...
Gregorious77 Posted March 7, 2010 Author Report Share Posted March 7, 2010 Well I have done 1000 miles since I got it and its not dead yet, and yes I do rev it too. the induction roar is addicting. Link to comment Share on other sites More sharing options...
Gregorious77 Posted March 18, 2010 Author Report Share Posted March 18, 2010 Clutch Basket had play in it, I have replaced the bearing and there is still play in it. I have now ordered the bush that sits between the shaft and the bearing in case it is that, that is worn. Link to comment Share on other sites More sharing options...
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