The Matrix: Rebuilding By runningslow (Read 26,563 times)

[kz1000st]

Right now, there's no filter in my airbox. Could a restricted exhaust cause the same thing?

Possibly but the couple of times I dealt with that issue the plugs read OK. Are you sure the enrichener isn't stuck or something has gotten stuck in the entrance to the air box? I'd try pulling off the airbox hose on the carb and see if it makes a difference.

[runningslow]

Feb 23, 2012 9:56:45 GMT -6 kz1000st said:

Right now, there's no filter in my airbox. Could a restricted exhaust cause the same thing?

Possibly but the couple of times I dealt with that issue the plugs read OK. Are you sure the enrichener isn't stuck or something has gotten stuck in the entrance to the air box? I'd try pulling off the airbox hose on the carb and see if it makes a difference.

I don't think there is anything restricting the airbox, but that's easy enough to check.

[kz1000st]

Plus I've never screwed around with the things but I recall that carbs have fuel and air adjustments at the ends of the carbs. Maybe something out in left field like crud under the air adjustment screw. See, usually over rich plugs read black and wet looking. Soot, to me, means an airflow problem.

How's this for an exhaust restriction?


The plug was nice and brown when I pulled it after pulling off the head to replace blown springs.

[bcgreatness]

lakeland.craigslist.org/mcy/2846979360.html

he says that it has 76 thousand miles on it, i think he means 7,600 miles lol i would be very supprised to see that scoot with almost 80 thousand on it.

[runningslow]

Hah. That looks familiar! Only mine is purple (UM claimed it was blue....)
I also don't have the factory mirrors anymore. I like my bar ends much better.

Curious body damage. I wonder how one manages that??

I'm impressed that it still has the factory exhaust. Mine rusted out ages ago. Actually, I went through two of them. I had the original one replaced under warranty, then the second one got modified by the dealer I bought it from.

[bcgreatness]

Maybe it would make a good parts bike?

[runningslow]

Yeah... but it would be the other way around.
Mine would be the parts bike.

But, in all honesty, even if I offer $1000.... I may as well just buy a fresh new engine and a nice new exhaust for mine and be done with it.

[bcgreatness]

yeah you could do that BUT all you will have is an engine, with ths bike you will have every part of it, only way it would not be good is if the engine is bad on it, who knows. atleast it would save you from having to try to find a hard to locate part and then order it n wait. was just and idea yeah IMO 1k is too much for that thing, who knows what could be wrong with it anyways.

[runningslow]

Well... replacing the carb fixed one problem! I could get it rev up without dying... but...

After a little while of idling with the occasional rev, it started to make a bit a of an excessive rattling sound and eventually cut out. Now it won't stay running. I wonder if I may have a broken valve. I was too frustrated, plus I had other things to do, so I didn't dig into it.

[roketafan]

sounds like the valves maybe they backed off adjustment that is

[runningslow]

Ok, so I finally got around to messing with this again.

I checked the valves, both were tight. I readjusted them, buttoned the scooter back up and tried starting it. Ran and idled fine again for a few minutes. So, I shut her down, aired up the tires and as I was getting ready to go for a quick test ride when it started making a rattling sound again.

Unfazed by this, I decided to open up the CVT to see if perhaps the rollers were misaligned, or something else of that nature. Found nothing wrong in there, left the variator off and tried to start it again. Still rattling. So... not CVT.

I'm going to let it cool down again and check the valves, again.

Thoughts??

[sprocket]

Sure you haven't dropped a valve adjuster lock nut somewhere..sometimes they can back-off and float around the valves until they find their way into the exhaust valve. BANG!!!

[runningslow]

Pretty sure, but I'll let you know when I open it up again. They were both there when I opened it up today when I adjusted them.

Sent from my MoPho using the ProBoards App

[runningslow]

I've had some legitimate reasons for a lack of urgency to fix this scooter (which is a story for another thread), but still even then the amount of time I am able to find to work on this thing is sparse..... wow.

Anyway. I finally got around to opening it up again. The exhaust valve was a little loose, but not too bad. I reset it to .004, buttoned it back up and tried to start it. It took a few tries (after sitting for a few weeks), but I got it to start. It idled OK for about a minute, then it started making this rattling, almost a squeaking sound. I should probably go an try to record it, but I'm afraid of doing irreparable damage at this point.

Frankly, to me it sounds like it could be an unlubricated bearing, perhaps at the cam. When I opened up valve cover, moments after it started making the sound, there was little to no oil in there.... there's supposed to be, right???

Going back more than a few months (since its been just that long), I'm wondering if plugging my oil cooler lines is actually blocking oil flow into the head? I don't know how the oil passages work in these QMK motors, but is there a chance oil is supposed to flow thru the cooler and into the head?

[runningslow]

Does anyone have any thoughts on my previous post?

I think I'm going to splice together a short hose to connect the two oil cooler ports so that I can get some oil flowing through it to rule out anything related to that.