Hesitation after mods
 

Hi all... I just replaced my piston, rings, went from a stock cam to an A13, then replaced the belt and went with a 1500 torque spring. Mid range is definitely improved. I don't really struggle going through mud and up hills so I got what I wanted. Rear tires more readily break loose from the torque when getting into it. I'm trying to take it relatively easy to let the rings break in them in doing an oil change this weekend.

I have noticed if I stab the throttle from idle, there is about a second of hesitation that I didn't have previously, then I move w/authority. Going to check for anything loose or a vacuum leak. I did a real rough adjustment on the idle air valve but will look more into that. I did reset my valves to .004. They were both very tight when I was reassembling.

Have read the plug... I only have about 10 minutes of total runtime. W/the different cam, can I expect to have to rejet? Any pointers or 'break in' recommendations appreciated. I just plan on not running it too hard and varying RPM for a couple hours of operation and change the oil.

One last question, I have a newish (1 month old) battery and have had no problems cranking. It now seems quite a bit harder to crank I attributed to high compression from the rings. I turned it by hand when I installed the cam at TDC and it turned by hand, through it was much tighter than before. Figure that's normal?

Been out running around a bit. Definitely have to rejet. It's a rapid acceleration to 25ish... but I think that's about it's top speed now. Might go back to the old spring and see if I can get a little back and let the CVT shift up as it doesn't seem to be upshifting at all as of now.

Forum seems... dead. Been posting a handful of times the past few days and it's been a one sided conversation. Hope all the folks are not posting because their out riding...

Well, I have 12g sliders I put in a year or so ago. I ordered some 14gs to see if I can get it to upshift. Read the plug and I'm definitely lean. I think I had a 114 stock and I either have a 120 or 125 in there now that I installed after I got rid of the stock airbox. I'll go up by 10 and read again. Maybe a little more power will force a shift as well. It just doesn't seem to ever unwind the CVT. I know the new belt was SUPER tight compared to the old one so maybe it needs to stretch a little. I run a lot of rpm slow which was desirable for the torque but I don't think it has the power right now to pull high rpm at speed... though the A13 may be the culprit. I figured from some stuff I read that I would do well with it.

Once I rejet, I'll do a couple short bursts w/a gps to check speed and see if it cures the slight hesitation I get when I go from idle immediately to full throttle. If I go full throttle a little slower, I don't get it. I've only done a few short bursts really to read the plug.

I had a similar issue with my HH 250SS. I was getting a hesitation when I would floor the pedal. But then I noticed when I first start it cold, it had no hesitation when gunning the throttle. Because the fuel enrichner needle had not extended yet. So I upjetted the pilot from 40 to 42, and then to 45 and it no longer has had a issue. Spark plug reads the correct brown color too.
Of course i have a mildly modded SS and the engine size is larger than yours, but the fuel enrichner(choke) works the same as most 150's. Your jet sizes will probably be lower.

Fooling around, I'm at a 130, up from a 120. I could probably stand to go to a 135. I ran a 130, 140 then 135... then back to the 130.

I found the hesitation was from needing to adjust the fuel enrichment valve. I thought it was jet related but I think that was my main problem. Jet is a little white still on a 130. I figure I oughta get a new plug one of these days too... it's insulator is almost indistinguishable from the electrode... it's the same plug that cane w/the buggy.

Pretty hot out right now and am taking a break. I'll try going back to the 135 and adjust to eliminate the hesitation going from idle to full throttle. It's amazing how if it's off, you either get a rev hang when you gun it from idle or a hesitation... doesn't take much to throw it off.

While I don't have a good long straight I can run the buggy on w/o getting negative attention, I did do a couple blast and get to about 27-28 mph in what I'd guess to be 100-150 yards, give or take with it still slowly building speed, so I oughta still be topping out above 30 given enough road. It would crack 35 given a lot of road in the past, but I never saw 40.

I oughta have the 14g sliders to swap out the 12g sliders to so if I can get a little more top end/lower rpm cruising w/o sacrificing the bottom end.

When I had a Kazuma Coyote 150, it had 12.5g rollers stock. I was very happy with those and never changed them.
The Kazuma was cheaply built buggy and the roll bars were a smaller diameter than most other buggies. But that also made it very light weight too. So it would move really good. All my friends who drove it couldn't believe it was only 150cc's.
It had a lot of other issues, but power wasn't one of them. I sometimes still miss that cheaply built rough riding piece of junk though lol. I don't miss always fixing it after every ride. Usually the reverse gearbox would break once a year....nope I don't miss it after all.

Mines hanging in there. It's seeing at lot of use right now. With all the rain we've been having, it's the only way I have to go fish at a couple retention pond a mile or so behind my house.

At least I don't leave a smoky trail behind me anymore. When I pulled the piston, there was a little wear but it's actually looked like the Gap in all the rings had somehow moved to line up. Cylinder looked great. Never had a sprocket/gear problem yet... hopefully it stays that way. Other than putting some amsoil in the tranny 1-2 years ago, I haven't done anything to the gearset. Old stuff was clean when it came out.