thought jetting, but now it's electrical. thoughts or ideas?

[davidbogart]

From what I gather about the Cdi is that no it will not run with a faulty cdi. What I can't recall is if u have adjusted your valves or not probably not the culprit but worth checking and verifying correct valve lash clearances. It's always a good idea to rule out things that don't require u buy new parts like : spark plug gap, valve lash, double even triple check the carb is clean, that all breather tubes for the crankcase and gas tank are not plugged or blocked, electrical connections , no head gasket or intake boot leaks, proper petcock flow from gas tank to carb and check for proper air flow to the air box. These are a few things to double check I know they are redundant but are free to check and help narrow it down I personally think your air to fuel mixture is off but I have been wrong plenty before. I hope to see those pics soon

[Horri]

Speaking of that airbox..I don't see any picture s of it and it's openings to fresh air in that other thread..As David mentions..maybe

it just isn't getting enough air..Have you got any pictures of it and the holes you have in it to allow air in..Or,,have you tried

running it without the airbox connected,,,???

Edited January 13, 2014 by Horri

[unclejtl]

i have checked , i beleive all those things, but will again. the first thing i did when i got it before starting it for the first time, was the valve adj. on that note, at idle, it's relatively quiet, a few rpm higher, it's alot noisier. this is my first 600 (my other xrs are 200 and 250) so i figured it might be normal... i dont have a way to read the rpms, so not sure of the point it gets noisier, but it's a sudden change.

 

here is a pict i have of the airbox, but now it has a lid on it with a square hole in it. more picts later. i will remove the lid and see how it runs.

 

here is a link to my album at photobucket of the "build" http://s89.photobucket.com/user/unclejtl/library/xr600?sort=3&page=1#/user/unclejtl/library/xr600?sort=3&page=1&_suid=1389646435202009149993415994351

 

[Horri]

mmm..Looks adequate..Filter???,,Give it a try anyway..

[unclejtl]

filter is a UNI. i used the factory intake to "eliminate" problems..... 

[unclejtl]

well, life got in the way last night, so no time to get pict or video or try to run without airbox lid. today I will be home by 4, so will do then.

 

thanks for your input.

[unclejtl]

here is the top of the airbox.

 

the videos of the cutting out don't sound as bad as in real life, but it's at all throttle openings.

 

the video of me turning down the idle, it to show the noise difference at a higher idle.

 

 

 

videos

 

 

 

huh...

well, you can see them here http://s89.photobucket.com/user/unclejtl/library/xr600?sort=3&page=1

 

thanks.

Edited January 15, 2014 by unclejtl

[Horri]

Had a look at the vids,,and yep you're right ,,can hardly pick the cutting out. Almost sounds normal to me apart from the engine sounding

a tiny bit rattly ..maybe cam chain or tappet/rockers. Would it or them be causing it..I doubt it..

 

I don't know uncle,,That airbox looks good enough and no change with the top off.??.Is that a small filter on top of that bottom crankcase

engine breather...Can't imagine it'd be having any affect,,Have you tried it with just a hunk of pipe running down to the bottom of the motor,,any difference??

I've never had any sort of filter on that breather on any 600 I owned or any other XR/XL I've owned,.rubber pipe to bottom of the motor,,that's it..Although

I do admit my current bike has the split rubber pipe with one bit running up under the seat,,still no filters though,,

Clutching at straws,,in essence,,I don't know..

Edited January 15, 2014 by Horri

[unclejtl]

its funny, the bike is alot louder in real life. i might have to try the video again, just not wanting to piss off the new neighbors ?

 

i will have to look in the manual and see if the cam chain is adjustable like my xr200. i will check the rocker/valve clearance again.

 

no change with the airbox top off ,on the kickstand, didnt ride it though.

 

the filter on the crankcase is just to keep dirt out. i know others running them and no effect.

 

thanks for your input Horri ?

[davidbogart]

Definitely can hear the miss in the mid rpms not so much at lower rpms. I know you have adjusted them valves when u got the bike but you should check them again they do sound a little ticky (if that's a word) but I've heard worst. On a side note I have a 85 xr600r that had a ticking noise I couldn't quite pin point I thought was the valves. so i replaced the cam chain, adjusted the valves more than 2 times and still couldn't find my problem until it as to late it ended up being excessive wrist pin clearance and caused my piston to go past "zero deck" and hit a valve. funny thing was it ran great didn't smoke and started like a champ it just ticked a little at idle but got worst with rpm so after I tore it down found the problem and took it to the machine shop we noticed that the cylinder and piston rings were well within spec when we check the ring end gaps and cylinder bore. I never did find what caused the excessive wear on the wrist pin . So I know this story doesn't really help but if you check your valves and replace the timing chain and it still ticks this is something to suspect.

[unclejtl]

yep, and the miss gets louder with higher rpms, just tried to be kind to the neeighbors. it's ALOT louder in person than the video.

 

will check valve lash again when time permits (still moving).

 

thats interesting about the wrist pin. i'll keep it in mind.

 

thanks davidbogart!

[jjktmrider]

If you want to check for wrist pin or crank bearing slop you can take the spark plug out. Turn the motor over till it just goes past TDC, then stick a dowel or rod down the plug hole on to the top of piston. Now watch, feel, and listen closely as you pushing down on the rod to see if the piston moves. Any movement other than if it turns the motor over is not good.

Edited January 16, 2014 by jjktmrider

[unclejtl]

i'll try that this weekend. Thanks!

[davidbogart]

Good idea JJ . You gotta love the simple tests like that.

[unclejtl]

well, i finally got time to get back to it. life is just too busy sometimes... it turned out to be the coil. while away for work, i ordered a ricks coil and cdi box, just to try. put the coil on and wahlah... runs great. put the cdi box on anyway. thanks for all the input! sad thing is i think i have to sell it now. i started this a year nad a half ago, and since, my balance just isn't what it use to be and i'm getting a little nervous on the road, with all the cell phone texters and whatnot...

 

anyway thanks to all who input, that's what makes these forums so great!