Well, I just completed a complete engine overhaul on my daughters 1998 LT80. Top and bottom end, crank bearings and seals, new crankshaft, piston, rings, wrist pin, circlips, wrist pin bearing, as well as new clutch sheave, rollers and roller plate. Took me about 7 hours to complete altogether, all parts were OEM Suzuki replacements. I started it and let it run and idle for about 10 minutes, shut it off and let it cool down for 20-25 minutes. Then started it and let it run/idle for another 10 minutes, and again shut it off and its now cooling down for a second time.

I'm expecting my wife and daughter to be home any minute now. Is it ok to let her drive it around the yard, or is there something else I should be doing to help break the piston and rings in? I know shes going to be eager to drive it, she only drove it once this spring.

Thanks for any advice.

 

I would alter the throttle stop on the handlebars so it will not rev too hard, with luck it could be an hour or two before she decides it is a bit slow.

 

Ok. I think I'll turn it down to 1/2 - 5/8 throttle. How many hours before it should be safe to turn it back up?

When my daughter got home yesterday, immediately after supper she wanted to ride it. She's used to riding this ATV at 3/4 - full throttle, she had been up until it died on her a few months ago and I started the rebuild. But I told her she couldn't use full throttle and that she should vary it quite a bit while driving it. She only got to drive it for 10 mins until she drove up beside me, stopped and the engine stalled out at idle. Not a big deal, but I spent the next 1/2 hour adjusting the idle speed and throttle cable free play until I had it idling good again.

I think she was a bit upset that I had kicked her off so soon, and today I know she will be asking me to ride it again. But before she jumps on, I'll adjust the limiter for peace of mind. BTW, even with me on it (~200 lbs), the throttle is very snappy now and the engine is way quieter. After comparing the bearing play in the two cranks, the old one was missing every needle bearing from the connecting rod and there is at least 3/16" movement up and down. How the guy who put the top-end on it last summer missed that (previous owner), just completely baffles me. But the fact that he re-used the old piston pin bearing and it self-destructed and took out both crank bearings, and what was left of the big-end bearing, just pisses me off! At least now I know everything is new, and this ATV should be good for another 2 or 3 kids in the future.

 

I would keep it down for a while, it's safer for her and can't hurt the engine. If she gets to complaining that it could be faster, turn it up.

 

Just let her ride it and have fun.. their are many debates on how to properly break in a engine. Full throttle , part throttle, cycle the engine. your can find about the same amount of benefits and drawbacks to each method. Change out the oil after a few hours and it should be good for years to come

 

A wiseco piston would demand a meticulous break in.
Suzuki piston~ you've done good. Now, run it like she stole it.
Change the oil...Now that's funny Z.

 

LT80, from your responses to other members posts on the same topic, I think that's the answer I was waiting to hear . Yeah I chuckled a bit too when I saw the oil change recommendation, but its ok Something I am going to start doing is researching the best 2 stroke mixing oil, now that everything is new. I'd like to keep it running its best and use the best oil I can to keep it that way. Thanks again guys!

 

Ok ok ... not familiar with the 80 did not realize it was 2 stroke..LOL

As far as mix oil.. boss runs whatever he has on hand engine oil, trans oil, you name it. Darn things start and run perfectly everytime..LOL

 

That's OK Zrock, We can't know it all.
You help alot of ppl in here on alot of machines.

2 stroke oil: I use and recommend Torco GP-7.
You have to go to the Torco.com site and there will be something to click on that sends you to ppl that handles the retail side. Unless you're lucky enough to find it locally. It's a rare find.
Red Line and Klotz R-50 is good too.
This subject has a wide opinion range. LOL