86 250r Engine noise...what's making it? You tube video to hear!

[Taiser]

Hey guys, thanks for all the help last time, it really helped narrow it down. Now she fires up on first kick, idles GREAT and puts out tons of power! Only one thing is still making me pull my hair out. This weird noise from the engine!

Don't know what's causing it. Sounds like it's coming from the reed's but I've never heard them make this kind of noise (although my 2 stroke experience is limited to 20 years ago on a YZ) so I'm looking for input. Again she has tons of power, compression is 175# and this is almost new engine. Noise is weirdly consistent and steady. Got buddies that say it's normal (I don't think so), some say too much oil in the gas, others that it's the counter-balancer. Any ideas would be helpful, I'm sure someone has heard this before!

You tube video here...

http://www.youtube.com/watch?v=JoRPc56emmo

Don't mind the smoke, I've mixed the first tank pretty thick to break it in.

[badasskfx]

sounds like the bottom end is ratteling. did it just start to do it? or are you just noticing it?

[fabiodriven]

That sounds alot like my Tecate (250) at idle. In my case, I beleive it's the actual sound of the piston going up and down, and whatever clearance there is on either side of the rod making that little rattle. I've always imagined that's what I'm hearing because if you run it without the rotor cover you can see the speed the engine is running at and almost imagine the piston going up and down in sync. I'm not 100% certain that's the noise in either case (yours or mine), but it's an educated guess. Mine has always done it. I've had it for 4 years, had the motor apart, and she's always run flawless. I just got used to the noise. I've never owned an R, so I can't say if that's normal or not for you.

[HondaHarry]

Ive been told thats normal... the notorious 250R counterbalancer rattle.
When I first got my 85 250R I noticed it too, and it freaked me out, I posted
on here, took it to a shop that my freind Kelly runs, (Best motorcycle mechanic I know) and after he got done giving me hell for buying a trike, he said it might be piston slap (but it is/was an extremely low hour motor that had just been gone thru with new seals, clutch update, and an 86 ATC cylinder with an old LA Sleeve 295 kit. (I still have the 85 cylinder, and its std. bore with zero wear) Anyhow he told me to just ride it and see if it got worse, when the motor was really warm it would become just a touch more noticable, but never had any ill effects, and nothing weird ever showed up in the oil. I have heard some bikes rattle louder than others, and I have heard this noise to varying degrees on many many 250Rs. That was my experience, and my $0.02. HH

[Itrike]

I don't know what makes that noise but my 85 stock piston bike made it and so did my parts bike and the 86 r I had for a short time. Kinda funny just this weekend at silver lake I was talking with an older gentelman who has a couple really fast 85 rs he has had for a long time and built them himself. I mentioned I was thinking of building a big bore motor for my trike and he said when I do not to get excited abought the honda rattle. I wonder if this is what he is talking abought??

[Erics350x]

That isn't normal noise. Does it get faster or louder with the RPM's?

[fabiodriven]

That isn't normal noise. Does it get faster or louder with the RPM's?

No offense, Eric, do you own any 2 strokes? That would be a terrible noise for a four stroke, but mines been making a similar noise for years, and I don't baby her...

[Yamatrike400]

Yeah mine sounds like that when i push down the kick starter while its running..It does slightly make that noise, but not as loud.

[Tri-Z Pilot]

almost has a noisy valve train kinda sound to it, kinda like rocker arms outta whack. seeing as that dont apply here, its definately something connected to the rotation of the crankshaft, its not something just rattling by itself.

[iowarotax]

Most of the Liquid Rs I have owned have had a little counter balancer noise, but not that loud. Usually its just a low buzzing noise.

[Daddio]

It sounds like the counter balancer to me.
Here is 1upfront and his 83 250r. It sounds a little different but you can still hear it.


Here is his 84 300r drag trike. It is too loud to hear anything but the exhaust noise.

[freaksfix]

I have owned 10-12 250r's 85 86atc and trx's 86 87.. They have all made that noise, they all have varied in how loud it was but never as loud as yours.. anyhow i never figured it out on what it was but never had any problem that related to it. and when ever i replaced crank bearings or topends or rebuilt trannys ect it never went away... weither its normal or not im not sure but it has never shown i real problem...

[Dammit!]

Mine has been doing that the entire 18 or so years I've owned it.

[Dammit!]

Wait for the end of the vid. I was having to work the choke to keep it from dying. You can here it best at idle.

http://www.triketrash.com/random/250rknock.mov

Edit: after listening to yours again, that is really loud. I have a somewhat loud pipe though. Maybe it's just being drowned out more.

[SCEADU]

My 88 does it too. I thought that it was the cranik bearings but I was asured by a mechanic that it was normal.