YT125L bogs down in 3rd+

[RyanRX7]

Ok i have this YT125L I picked up a few weeks ago and for some reason it has good pick up in first and second, but third, fourth, and fifth (you can barely even go anywhere in fifth unles you totaly max fourth all the way before you shift)seem very underpowered. It seems to bog down a good bit, what's the deal??? The carb is nice and clean and the plug looks good. Also when you rev it high it makes like a pinging vibrating noise, sounds like it will fly apart but obviously it does not, could that be rings maybe???? Or does it sound more like something lose, it seems to me like it was comming from the top end. I was thinking that if it was rings that it wouldn't start as easy as it does. Also I have been running premix with the oil injection disconnected to be safe. Anyone ever messed with one of these to give it some good pick up, or done any gearing work with one???

[short4stuff]

my 175 tri-moto does the same thing but just in 5th ... anyone?

[compaqkoci]

burn premium gas in it not regular :)

[short4stuff]

burn premium gas in it not regular :)

really?? that will make all the difference? I am running regular which I think is 89 or 87 octane!

[thefox]

I would check the exhaust pipe and exhaust port to make sure that it is not pluged. I do not have must experience with 2 stroke trikes but I have had the same type of thing happen on a moped. And besides, it is a cheap and easy thing to check.

[short4stuff]

hey, would my pipe being "blown" up at the end cause this ??? its sort of like a straight pipe now.. i can see the baffle.

[yamaha200E]

lol my ytm 200 is just like that(the exuast) i like the way it sounds (nabiors dont lol) but it bogged in 3+. and i was mad at it and for got that the half choke was on lol i turned it off and runs good. so u might wanna check that masy not be trailprotrailpro problem though. ;)
kyle

[short4stuff]

yeah but mines a 2 stroke ....

[RyanRX7]

yea ours are 2 strokes and this problem is so retarded. It's a good ride till you hit third, unless you totaly pin second then it has some power. Are these 125s that weak, I mean it can't pull me up a decent sized hill in first (I'm about 190).

[yamaha200E]

well man first of all look at how old it is. 2nd its made for yonger kids starting off. it prolly needs rebuilt man. if u want to sell it id buy it looking for one for my little bro. ;)
thanx kyle

[compaqkoci]

yea burning a lower octane give you less power and lets more carbon build up on your motor parts... 92 or 93 octane what we got here and works good. when you use a low octane that can cause engine pinging and can be your problem...also!! what kind of 2 stroke oil do you use and at what mixture? Question how many kicks does it take to start cold? :?

[RyanRX7]

Well the choke cable is broke so I guess that's always off, and with no choke it takes about 10 pulls if left parked outside in 40 degree weather. If I reach down and pull the cable when it's running it dies.....all the other 2 strokes I have just run like crap if I do that (they are dirtbikes). I run high octane and make premix (don't like that oil pump, don't trust it). I use some mid grade 2 stroke oil miked at 32:1. Plug seems to look good, and the bike has good pickup in the first 2 gears....I can't understand why 3rd is so slow.

[compaqkoci]

check you gas lines for fro cracks that can suck in air and your petcock check that too mine a a bead seal and when i got it revved up it would suck air in the engone and bog down bad . about you cold starting it 10 pulls is not much so i dont think it has seals going. can you do a compression check on it? :D what kind of choke is it like a little knob you pull up is that brokken? i would replace that may be your problem ;)

[TimSr]

This sounds about typical, and it doesnt sound like anything is wrong with it to me. When I had mine, I weighed about 160, and it couldnt hold 5th gear on flat pavement. The stock gearing was exetremely low, though, so I never had trouble pulling hills in low gear. It could easily go up a lot more hills than it could safely come down! There area few tidbits in this thread amongst the nonsense that might help. Low compression robs you of low end power, so compression check may give you some insight as to your top end condition. The other thing that was mentioned is your exhaust. They were poorly designed on these to begin with, but make sure ist not obstructed or reduced in any way. Along the same lines, make sure your intake is clear (Air filter). If your chaoke cable is broke, make sure the chock is in fact "off" by checking where the plunger goes into the carb.

Overall, this sounds typical to me, and theres probably nothing worng. Its a 125 2 stroke from the early 80's, and they are very limited.

[yt125l rider]

i have one and my used to bog down in third but i put .8 qt of motor oil of 30w in the transmission. it runs fine. im a 300lb guy and get it in to 5 and ride fast. my uncle rides it to he only goes to third bc he does not like to push the speed and he is 550 to 600 lbs so u must have a problem. it also starts first mb second pull in 10 degree weather and has not been ran in a couple of weeks bc it is at my uncles cabin

[old-yellow]

I had the same problem after I rebuilt my 125 tri-moto. It made that same noise but It turn out to be a leaky head gasket. Do a compression check on it it could be low but I would check around your head gasket for oil if it is leaking use copper seal on it. just my two cents. Thanks Alex