lt 80 -wiseco piston problems

[SRH]

me and my buddy both had new bores with wiseco pistons done at the same time.... put them together...ran great first 2 rides..then they got hard to start...then they ll together quit, we pulld them apart after doing a compression test...which was 52 psi, after 1 tank of gas, piston was like new...there was some browing on the piston by where the rings end, and the rings appeared to be worn, the jug and piston all seem within spec but the end gap is off....

is it possible we got the wrong rings on 2 pistons? if not what would cause them to wear out so fast?

[LT80]

Which way did you point the arrow on the piston?
Rings upside down? (doubtful)

[SRH]

arrow towards the exhaust, rings were in the right way

[LT80]

And some wonder why I recommend Zuki pistons (up to 1.0 over).

With 2 doing it, it narrows down some things I guess. ie: dirty air,electrical prob,oil inj...
But anyways, what oil are you using? Using the injection? Mix a lil oil in tank w/the injection? If no injection, what ratio of mix?
A sustained WOT?

Wiseco's demand a meticulous break in. A local guy that is known for high quality work recommends a 4 tank break in. I bet your also thinking 4 tanks is excessive.

[SRH]

premix , maxima castor 927 20:1, neither of them were run hard, we didnt even make it thru a whole tank, clean air , piston is like brand new, cylinder doesnt even have hatch mark worn off, my buddy doesnt have the csh but im buying a oem jug and putting a stock piston in it...wiseco is junk or the bore guy is a dip****...

[LT80]

What size did you bore to?
Not going to try a stock piston?(1.0 or under)

[SRH]

not sure i think mine is 1.5 but dont quote me on that, and my buddies is max, wouldnt the clearance its bored to for a wiseco not work without boring again for a oem piston?

[LT80]

Suzuki only makes pistons to 1.0 over
Yours are 1.5 and 2.0 over......A good reason to use a wiseco.

Usually it's a sticking problem and not what you're expieriencing. I've not seen what is happening here.
Piston to wall clearance should have been .0035 from the bore guy.
I'm not a 927 fan but I doubt that did it. As you know, 927 separates in the cold.
I like Torco GP-7 2 stroke oil (full synthetic) Torcousa.com
I really believe it's a superior oil by what I've used and seen (inside motors) over the years.

Hmmmm.... how's the champher on the ports (the bore guy did this)? That's about the only thing that I can think of (or clearance) that would do this..Is this a place that does boring or a machine shop that helped a brotha out?
:confused:

[SRH]

Originally posted by LT80
Suzuki only makes pistons to 1.0 over
Yours are 1.5 and 2.0 over......A good reason to use a wiseco.

Usually it's a sticking problem and not what you're expieriencing. I've not seen what is happening here.
Piston to wall clearance should have been .0035 from the bore guy.
I'm not a 927 fan but I doubt that did it. As you know, 927 separates in the cold.
I like Torco GP-7 2 stroke oil (full synthetic) Torcousa.com
I really believe it's a superior oil by what I've used and seen (inside motors) over the years.

Hmmmm.... how's the champher on the ports (the bore guy did this)? That's about the only thing that I can think of (or clearance) that would do this..Is this a place that does boring or a machine shop that helped a brotha out?
:confused:

no they regularly do boring, i didnt know 927 seperated in the cold, it was actually cold out that day... ill switch to different premix on this top end....idk if i can get torco, what about klotz? thats what i used in all my 2 stroke mx bikes

the champher on the ports is what i was wondering, nothing looked to out of the norm, i really feel the clearance is out of whack, we took it to one expirience mechanic and he said it didnt really look bad but he thought it had too much clearance if anything, 6 thousandths i beleive he said...but we took it to the bore place and 2 mechanics there checked it and said its to wiseco specs...but they said the rings had too much end gap...they said wiseco sent the wrong rings...so there throwing a new set of rings on it, and want to see what it will do...of course it will run...but for how long we will see...if i had to guess 3 hrs and well be back to 50 psi...in which case im going to push for a cylinder replacement ....

let me ask you this...we initially took this lt 80 there needing a bore...it was on std bore....we got it back maxxed out:huh how is that possible? this is even more of the reason i want to push for a replacement if it does it again...

also is it possible if he had the boring bar off to get the bore offset?

[LT80]

I liked klotz R-50. or go to torcousa.com
If you look, the bottle of 927 says that it'll separate, at least mine did 14 years ago. :)

I'd like to think that once the correct rings are installed (if it was indeed the wrong rings) it'll be fine.
Wiseco specs eh.....like I said, it should have been .0035
.006 should run ok. I've seen many running .010... Wiseco's do swell.
Now for the bad part. Lame-o's really screwed you on bore size. I've seen masssive gouges taken out with the first overbore (.5)
I'd be pissed. They must have had those pistons sitting on the shelf or their supplier did. I'd be having a conversation w/em...
Doubtfull the bore bar is bad.
Knowing all this, I wonder if the 927 did it.
Anyways, good luck and let us know the results please.

[SRH]

well gvot it back thbey said pipe must be plugged ...they said it would only start without the exhaust on...changed out exhausts, cranked it over it would act like it wanted to run but would not take off and run...they threw new rings in and claim 120psi of compression,i have not done a compression test yet...could this be a reed related issue?

[LT80]

So did you blow thru the pipe and see if it was indeed plugged? I put em in a fire and blow compressed air thru em. **carefull** it'll throw flames. <G>
Anyways, Doubtfull the reed would do this but you better check it anyways.

Other than needing freshened up, it ran before all this work?

[SRH]

yup, had a new top end rode it for about a tank of gas suddenly bogged out and we havent had it running since

[SRH]

well finally got a chance to tear into mine...which had a wiseco done by the same place.... had 52 psi of compression same as my buddies with the same ride time, was getting plenty of oil... i threw on a std oem top end and it fired right up...ring end gap looks fine, clearance looks fine...idk what the deal is...only thing i can think is hes not chamfering the ports and the rings are wearing...idk im at a loss, the end gap was within specs

[bradrenea]

I don't know anything about the oil you are using, but could you be mixing it too rich? 20:1 seems pretty rich for any kind of oil to me.
I recenlty rebuilt a polaris trailblazer for my brother in law. He is new to atv's and bought it blown up. Anyway, everything was right on the engine when I got it put back together. He bought some Motul synthetic oil and asked me how to mix it. I told him to mix it 50:1. He did not trust me and asked a couple shops, which told him to mix it 32:1. He rode it a couple times and parked it for a week. Went to start it and it would not start. Brought it back to me and I found it had no compression. I tore it apart and there was no wear on anything, but the rings had basically glued themselves to the piston from the too rich fuel/oil mixture.
I showed him the problem, soaked the piston to break the rings loose. I removed the rings, cleaned everything up, and reassembled. He now mixes 50:1 and has not had any more problems.:D

[LT80]

Oils are not created equall. LOL
There has been many conversations on which oils goo the rings up. Aparently we can add motul to the list.
I usually recommend the mix ratio that the oil company recommends. I think more importantly on the correct jetting to go along with the mix ratio.
20:1 was a staple in the days of petroleum based oils. Says 20:1 right on my 250R gas tank.

My oil favorites are:: Torco GP-7, Klotz R-50, and Maxima SuperM. All at 32:1 and no ring issues.
I do hear very good things about Red Line oils.

[bradrenea]

LT80, any experience with Amsoil?

[SRH]

i was only using 20:1 on the first tank then switching to 32:1 , i switched to klotz r 50, but im using up my tank of 32:1 maxima first, should tell me if theres any issues there, neither of our rings were stuck to the piston or anything of that sort im really doubting it was the oil, my jetting is on point as well

[bradrenea]

Like I said, I am not familair with the oil you were using. I know they are all different, so I thought I would throw it out there.

[bradrenea]

Originally posted by LT80
20:1 was a staple in the days of petroleum based oils. Says 20:1 right on my 250R gas tank.



My first two stroke was an 87 LT250R. Got it with a blown motor. Took it to a shop to get it rebuilt. They recommended BelRay MC1 mixed 40:1. I was pretty nervous about it at first since the Suzuki manual said 20:1. I figured out the oils had come a long way in the twenty years since the manual was printed.

[LT80]

I ran amsoil before at 50:1 (per directions).
To be honest, I have no opinion other than I'm sure it's a fine oil. I got a buddy that swears by it.

[SRH]

well tore into it today, one of the reed petals was broken, put another set of reeds into it and it fired right up...kinda strange on a 01 for the reeds to go bad isnt it?

[LT80]

It happens...
I don't think it has much to do with all the problems tho.