Predator engine carb for CHEAP

[pd]

Maybe drawing a little too much air along side a shaft
Just guessing .

Pete .

[carryall]

I never thought about "wiggling" the throttle shaft.  You'd think it would "leak" consistently tho?  I'm going to do another complete cleaning on it, and this time, I'll use compressed air using my little airgun with needle point in the holes.  For know I'll just ride it "as-is".  The only noticeable difference between the 2 carb set-ups is I need to 1/2 choke it when doing a hot re-start because I didn't put in the 140 E-tube.  Really no big deal.    

[pd]

It may be an effect at only that given shaft position . But , it could just be debris in a passage .

I hope you use brake cleaner and not carb cleaner when cleaning carbs .

I never use carb cleaner . It eats rubber and rubber type things ( seals , gaskets and orings ) . Not to mention that it doesn't really clean that well .

I always use non-chlorinated brake cleaner . Cleans quickly and very well , doesn't destroy rubber and leaves no residue .

Always wear eye protection when working with chemicals .

Pete .

[carryall]

   For lack of anything else to do, I pulled the "non-functioning" carb apart, and figured out the problem.  The little O-ring under the idle mixture screw was deformed.  I may have done it when I turned it all the way in, in order to count the number of turns for later reference.  Just thought I'd post the info so someone doesn't reject the carb as viable replacement.  While on the subject of "carbs", here's a little trick/tip if anyone wants to get a bit more rpms with the stock governor still set-up.  I haven't seen it posted so I'll just throw it out there.  Zip-tie thru the throttle spring will allow you to defeat the governor mechanism somewhat.   

[carryall]

     I needed to change main jet the other day to a #32 because with the cooler temps (50 degrees) the bike was running pretty "rich" with the #35 jet and 140 E-tube in it. I left the float and needle in and gave the carb a quick "shot" of brake cleaner thru the orfices and reassembled.   It must have deformed the rubber tip on the float needle because gas over flowed out the carb all over the place after re-installing it. I'm thinking it's not Viton tipped like most bigger/better quality carbs because it refused to seal properly afterwards.
   After swapping it out with a spare, and going for a quick test drive to make sure it was "good", I looked at the can of brake cleaner and noticed it didn't say it was non-chlorinated.  Next time I purchase brake cleaner I will check closer and will remove ALL rubber parts just in case!  Oh well, the concrete floor got cleaned really well under the bike anyways!  LOL 

[pd]

Ha . I know all too well about that 'user error' stuff .

I always use the non-chlorinated brake cleaner . It's a lot easier on any rubber than something like carb cleaner , which I will not use for anything .

Pete .

[carryall]

   I was really surprised at how a 25degree temp change can effect the air/fuel ratio on this engine, especially at lower RPMs.  I even swapped out the 140E-tube to a slightly less rich one (with couple more tube holes)
    Granted not a good pic of the sparkplug but, you can see how one side of the insulator is nice and tan and the other side is black.  Shows how indexing your plug can make a big difference.  I ran out of index washers when I installed this one.    

[carryall]

Not anything exciting but I swapped air filters to a velocity stack.  Not sure I like it though vs the 90 elbow one.  Opinions?

[pd]

Depending on the type of venturi in the carb , the velocity stack might get you a bit more performance .

I'd have to think that the stack will increase the 'noise' level .

As for looks , stacks always allude to high performance .

Pete .

[carryall]

   Between the exhaust and the engine noise (no clutch rattle tho ha, ha) No noticeable noise or performance difference at all.  The intake is still the same size, I just made the cone with screen fit the existing one.  As for performance, I ended up adjusting the throttle stop to prevent me from tooling around at 40mph+ all the time.  LOL.  It tops out now with the stop at about 38-40mph to avoid tickets and for safety.