View Full Version : Engine rattling

04-30-2010, 02:00 AM
I have almost 20 k on my r and am starting to hear rattling noises from the front jug.It could be the rear but who knows.Has anyone had issues with there valvetrain making noise.It especially makes a rattling noise under load after 5k and is noticed under part throttle after 5k comes in as well .Under 5 k it is rarely heard.My front 02 values are going crazy as well.In the mean time im throwing no codes and instead of letting it go lean at 85% front 100 rear I decided to lock the 02s out at 103 103 to be safe with my bbdfi program.No changes have been made to my map just locking the 02s.
Im just looking for some Ideas .I'm out of warranty and am wondering which route to go.I have a manual but am not ready to tackle this since its summer soon.
Id rather baby her until fall if I can to tear into her.

04-30-2010, 02:10 AM
Any mods? I'd suggest unlocking the 02's and datalog for your bike.

04-30-2010, 02:18 AM
Admittedly this is a silly question but....have you checked the exhaust flanges? When they're loose they sound like the crank is about to come out. Also I hate to say it but if the noise only comes during acceleration it sounds like it may be a bearing. Crank mains or lower rod bearings maybe. Good luck, Wayne

04-30-2010, 02:23 AM
I did a oil pressure test and a compression test last fall cause it was a faint noise.Both were high on the spec chart.I have thought about the exhaust flanges.Which ones are you talking about.Muffler or at the head?
There is no mods.All stock.
I thought about taking the exhaust flanges off and and copper silicone sealing them as it works great on my drag car.Just a light coat does wonders.

Its really wierd it comes and goes 5k up.
I thought maybe the chain guides could be loose and causing slap.

04-30-2010, 02:35 AM
The exhaust flanges at the head. Check the copper rings to see if they're squished or out of shape. And **** I'm sorry, on further reflection crank/rod bearings should only make noise when you back off the throttle. They shouldn't make noise on acceleration. Wayne

04-30-2010, 02:42 AM
oh good you were scaring me.I have a mustang and when my last 9 second motor started to go it knocked during accelleration.I pulled it and found two front rods were oblonged.So do motors knock on or off accelleration??

04-30-2010, 02:50 AM
I thought about throwing a loud exhaust on it and calling it a day.LOL
Could tight valves cause spark knock?

04-30-2010, 02:55 AM
Ok, as I understand it and from past experience...under acceleration worn rod bearings are under load and don't rattle, when you back off they're not loaded up and have room to slop around, making the knocking sound. However, this is a very short term thing, it gets worse very quickly. If this has been going on for some time as you say I can't imagine it's the crank or rods. Get yourself a long screwdriver and put your ear to the end of it. Put the tip all over the engine and listen. You'll be surprised how well it works finding the source of your noise. Wayne

04-30-2010, 03:08 AM
Maybe some debris got into the lifter and it’s not expanding all the way? Those things are pretty sensitive to stuff like that but that would make more of a ticking than a rattle I think.

04-30-2010, 03:23 AM
1125r dont have lifters I thought?
I agree with you race.Its been going on for almost a year now and If it was gonna go it wouldof went awhile ago.Thats what leads me to believe its a valve train issue or the drivechain/guide is rattling.I contacted erik on facebook and he said they might look at it.He is 5.5 hrs from me.But it would be cool to check out the place and have people that really know what to look for on these bikes.Not just a mechanic that looks at it and wants to put a hammer to it.lol

05-01-2010, 03:21 AM
Ahhh Jeeze, if Erik will look at it do the ride. So what if it's 5-6 hours away. And just to be clear, you're on an 1125-R? Pretty sure we thought you're running a 12-R. Wayne

05-01-2010, 04:06 PM
I don't know I have a book I thought about checking it out myself. I've done car engines so this can't be much harder.
As far as the lifter statement goes this is the 1125r forum section.
There is a lifter in the 1125r . It's located on the side of each jug for the cam chain tensioner. There is a Allen access plug on the side of each jug with a copper crush washer.
It rode it yesterday some more and check for exhaust leaks but I found none . Just a little air out of the donut. A Very small amount.
It only Makes noise under load mainly .I swear it sounds like spark knock.I have the fourth flash and thought about getting the new one. But I'd have to pay for it as my warrantys gone.
I checked my ecmspy paremeters and they all match my current EPROM.
I save it once I recieved the fourth flash. They match??

RT Performance
05-01-2010, 06:56 PM
a computer flash should be covered under epa emissions warranty 5 years and 50k (not 100% sure that applies to bikes i know cars are)
Have u tried adding some octane boost?

05-01-2010, 09:41 PM
Ya I tried it last year when I first heard it.
Its more noticeable.

Well I took the book out shook the dust off it and i went to town.2hrs got me at this point.

I might add that tearing into this thing wasnt really that bad compared to the liter bike.

My findings
exhaust clearances are
max .009
min .010

actual findings

.0085 and .0080
.0045 .0035

.005 .0055
.0085 .0085

My findings after 20k is that my valves are tightening up.

Anyone know where shims are available?

05-03-2010, 12:31 AM
Well after the adjustment of the tight valves.I found that it doesnt lay down anymore like it did Especially in second.But the noise still persists.I'm starting to believe its a balancing sprocket or something along those lines.Or it could be a bad coil or timing .Ill read the book more on ignition.