Hrs on 350 when you have rebuilt top end

[idsmokeu2]

How many hours are people waiting to do the top end on the 350's? I have 82 hrs on mine and am debating on whether or not to slap a new piston/rings in her within the next few months.

 

I've read some things about pros running 50 hrs on rebuilds (enduro guys) and their motor still in like new shape.

 

Also, how much have you had to spend on a complete piston/rings/gaskets. It looks like the piston is around 200$ and another 55 for the head gasket and 5 for the lower gasket.

[Woodsweapon350]

Your best bet is to buy the factory oem piston/cylinder. It's pricey but if you want it to last like your original it's the way to go. It will come in a box, piston already installed in the cylinder ready to go just install wrist pin and clips, and bolt the cylinder down. It's a little more pricey but the ease of installation and peace of mind are 100% worth it in my opinion

[SeanM327]

I'm not trying to debate you I'm just curious why you would spend all that money on a cylinder if you only need piston and rings and you can get away with shimming the valves.

[Woodsweapon350]

I suppose it's personal preference but in my opinions if the piston and rings are worn so is the cylinder. Factory parts are superior, I've learned that the hard way and the ease of installation and the peace of mind I have when doing my top end this way is just worth it to me. Not to mention a 4 stroke cylinder really isn't that expensive especially comparing to a two stroke cylinder

Edited October 16, 2013 by Woodsweapon350

[SeanM327]

I agree with you on oem parts but you gave me something to think about with that cylinder replacement.

[motonack]

How many hours are people waiting to do the top end on the 350's? I have 82 hrs on mine and am debating on whether or not to slap a new piston/rings in her within the next few months.

I've read some things about pros running 50 hrs on rebuilds (enduro guys) and their motor still in like new shape.

Also, how much have you had to spend on a complete piston/rings/gaskets. It looks like the piston is around 200$ and another 55 for the head gasket and 5 for the lower gasket.

My 2011 350 XC let go after 75 hours about a month ago. Nothing blew up, but my bike lost 20% compression basically overnight when it happened. Its debateable if it had to do with sucking a minute amount of dirt in right before this, but theres no way ill be letting my bike go over about 55-60 hours now on a piston/ring kit. Could have been much worse for my wallet.

[JS117]

My 2011 350 XC let go after 75 hours about a month ago. Nothing blew up, but my bike lost 20% compression basically overnight when it happened. Its debateable if it had to do with sucking a minute amount of dirt in right before this, but theres no way ill be letting my bike go over about 55-60 hours now on a piston/ring kit. Could have been much worse for my wallet.

 

How much should a piston/rings cost for a 350? I haven't looked into it yet but I'm coming up on 75 hours. 

[motonack]

How much should a piston/rings cost for a 350? I haven't looked into it yet but I'm coming up on 75 hours. 

Depending on what kind you get, it should be around $250-300.

[Hans Schmid]

There is a guy I ride with that has a 2011 350xcf and he has about 220hrs on the stock top-end. He's a fast trail rider but does ride a lot....

[idsmokeu2]

Your best bet is to buy the factory oem piston/cylinder. It's pricey but if you want it to last like your original it's the way to go. It will come in a box, piston already installed in the cylinder ready to go just install wrist pin and clips, and bolt the cylinder down. It's a little more pricey but the ease of installation and peace of mind are 100% worth it in my opinion

 

You are crazy, you will have over 1000$ in a regular rebuild. There is no reason to get a new cylinder, they don't wear down unless you get contaminates in there.

 

On a side note, the stock pistons in these bikes are Vertex pistons....

 

You must make too much money or something lol

 

 

 

My 2011 350 XC let go after 75 hours about a month ago. Nothing blew up, but my bike lost 20% compression basically overnight when it happened. Its debateable if it had to do with sucking a minute amount of dirt in right before this, but theres no way ill be letting my bike go over about 55-60 hours now on a piston/ring kit. Could have been much worse for my wallet.

 

I have had several people do theirs around 100 hrs, one guy got his hot and his rings seized to the cylinder around 50 hrs, I've heard of some 100+ hrs and the people who have too much money and don't ride much do theirs before 20-30 hrs...

 

 

How much should a piston/rings cost for a 350? I haven't looked into it yet but I'm coming up on 75 hours. 

 Piston assembly is about 200, head gasket and lower gasket are around 65 together. So 265 total... about $100 more than my crf450R...

 

 

 

I will probably end up taking mine apart and checking it out. 265$ is quite a bit for just a top end though...

[speedboot]

we have a broken con rod in our 2013 sxf 350 within 30 hours , so someone can ride 200 hours and the other not 30 , just depent how fast you go .

[Wfomx463]

I also estimated about 200 hrs on my 350sxf before i rebuilt it. it was getting really hard to start and valve clearances were still good. leakdown was only 4% and piston and rings looked ok still the cylinder was a little glazed though. i ran a ball hone through it and installed a #2 piston. been running great for another 75 hrs since. i say estimated because when i bought into hour meters i used to ride 150-200 hours a year. now i still ride a lot but not as frequently as i did back then. mine had 2 seasons of enduros and hare scrambles on it.  

yes my buddy sucked the smallest peice of dirt in and it jammed his compressin ring shut and he lost all compression after about 20 hrs. so air filter maintenece and cleanliness is super important on ktm four strokes.