>>Once I got the 3.3 broken in (heat cycle) the thing ran like a scalded
>>bear, rode wheelies until I decided to let it down, etc.
>>Temps after 2-3 high speed runs were in the 250s or so (ambient temps
>>Revs great, is super fast, decent smoke. But now wheelies went away.
>>I think it's because the LSN is too rich, but if I go leaner on it after a
>>WOT run the idle hangs pretty high for a few seconds while slowing down
>>(and you can hear the clutch chattering sometimes).
>>Then I thought maybe the clutch was going out as I noticed it jerking when
>>using the EZ start. Took it apart, clutch looked a little worn (maybe 3
>>gallons through it now, with just over 1 on the engine) but nothign
>>serious. Checked the bearings on the clutch and one was sticking a
>>little. Cleaned it up. Jerking while starting went away.
>>Still no wheelies. I do a 15 second idle then JAM and it's like it stays
>>at a lower RPM for 1-2 seconds while moving then takes off smoothly and at
>>a pretty even (but fast) rate (no burbling, lean hesitation, etc, just a
>>Weak clutch spring causing it to engage too early before it hits the
>>lowend power to take off? Or maybe I need to go further with the HSN
>>tuning and revisit LSN? It's at the point now where it does scream.
>>Richen it 1/4 turn and you can tell a HUGE difference with a big power
>>drop and lots more smoke.
>>Also using pinch test on LSN. RPMs rise a little and die at 2-3 seconds.
>>Any leaner and no rise in RPMs during pinch test. Any richer and RPMs go
>>up too high before dying (but still 3-4 seconds) and bottom end seems to
>>Have about 3 gallons on the clutch and 1-1.5 on the motor (which still has
>>great pinch). Yes, I smoked the rod on my first motor.. :) I blame it
>>on the Traxxas break in.. lol
>>Thanks for any suggestions!
> Have you checked for exhaust header and coupler leaks?
> Checked/Replaced the fuel hoses?
> Checked the fuel filter?
> Changed the glow plug to something a bit hotter?
> Verified that the slide is opening all the way when you pull the trigger?
> Perhaps bought a bad batch of fuel?
> Checked the driveline for binding?
> Checked the brakes to make sure they ain't dragging?
> Checked the air filter to see if it's excessively dirty?
Yep, checked all that. The only other change made was adding RDLogics
driveline shafts. Now, this COULD be the problem but IIRC it started
happening before this.
Seems to roll just fine. Brake are adjusted (were too loose before and
disc fell off causing a front flip), no leaks, etc.
I may try just richening up the LSN a little more to see how much worse
it may get. But, pinch test tells me that it's getting rich even with
1-2 hours richer. So does drivability.
It's already at least a turn out past flush... I know all machines are
different, but this is my 2nd 3.3 and never would it even run at flush
(too lean). Richer than I have now, drive around slowly and it bogs
pretty bad and if it dies, starting it is like restarting after killing
it by plugging the exhaust.. a little hard. Vs. starting it after a
pinch test where it starts right back up in a millisecond with EZ Start.
> It really <sounds> like a slight lean bog, but if richening the LSN and/or
> HSN didn't help matters, it ain't that.
The best way to describe the sound is "riding the clutch" on a dirt
bike. The sound itself doesn't tell me rich or lean (no
crackling/hesitation or bogging/4 stroking).
> It sounds like you know what you're doing and that you've tried all of the
> common sources of this problem. I doubt it's the clutch as others have
> suggested as a worn clutch causes RPM to increase d/t slippage rather than
> decrease RPM, but hey, you never know!
That's what I've found with these little ***s. You never know. :)
Tuned bikes and quads for years and this proved similar, but something
like this baffles me a bit and process of elimination starts up. :)