Gas Gas What type piston do u run??

yeah, the universal appeal. careful what you say about anything. I just remember this parade where some cruel, sorry son of a bitch had this pitbull in a skirt.
 
I am still thinking about something for the near future with an E button. I have a crf250 that has the transmission from a crfx in it. I have the cases it came out of, so i could put an electric start on that. I am thinking about a rig to keep in calif. I would like that one to be a 400-450 with E button. I had knee surgery last summer and I have reservations about that side of me being able to kick very long if I flood one or tweak the knee (easier to do that so far than I expected.)
 
Could have been. I figured if I asked no questions I wouldn't hear any lies. Reminded me of the time Floyd said he went home with this really hot young woman whose dog was on the same bed growling the whole time. He had been on the north slope a long time is all I could say.
 
Read what Vertex has to say about the life span of a two and four stroke piston.
http://www.na.vertexpistons.com/FAQs.aspx
What is the life of a two-stroke and four-stroke piston?
Piston life is relative to the operating conditions of the engine, so no exact life expectancy can be given. In a perfect world, about 20hrs is the max usage you want to try to get out of a piston. Again, this is all relative to use, maintenance, and operating conditions.
If you had the budget, it would always be best to change the piston and rings sooner than that. I could never afford to it that often myself. So I use the oils that I think work best to help prolong any replacement cost.
 
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Read what Vertex has to say about the life span of a two and four stroke piston.
http://www.na.vertexpistons.com/FAQs.aspx
What is the life of a two-stroke and four-stroke piston?
Piston life is relative to the operating conditions of the engine, so no exact life expectancy can be given. In a perfect world, about 20hrs is the max usage you want to try to get out of a piston. Again, this is all relative to use, maintenance, and operating conditions.
If you had the budget, it would always be best to change the piston and rings sooner than that. I could never afford to it that often myself. So I use the oils that I think work best to help prolong any replacement cost.
Of course they're going to give you a 20 hour max limit, life of the piston is dependent on factors such as rider skill (revving it out more) oil quality, and several others. That said, logically a person of average skill level is going to need less pistons than Justin Barcia, now when Vertex says that, they don't want any sort of liability (and more sales out of joe blow) for when a local pro who bangs a 250f off the rev limiter hops on it, he probably should be changing it every 20ish hours. Overkill for mortals like us though. 50-70 hours is a safe margin for those of us without super powers imo and expierence/word of mouth from the guys that actually turn the wrenches. Of course I run my oil for 10 hours too, but hey, scientifically, through oil tests and what not I could find 0 indication that it needed to be changed sooner. But thats just the way I do things.
 
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I would like to say that most of us are just recreational riders. Yes we do have some folks in here that actually race. And race hard. So this is for the benefit of the recreational riders, based off of my personal experience. Does your manual say to replace the rings and or rings and piston at........ Oh lets just say its every 10hrs of racing. Thats some serious abuse especially at race pace. So yes it makes sense to replace those items at that type in interval.

Now for the recreational rider. Sure we ride hard, or at least we think we ride hard. But do we really need to replace our piston rings and pistons at what the manual says we should? If I did that I wouldnt be able to afford to ride. Depending on what manufacture of piston and rings you buy, to include a complete gasket and seal kit. Reasonably you can expect to spend between $100 and $200 US dollars for everything you need. Now I try to ride as often as possible. But typically I ride about twice a month for as long as I have fuel for. Which is about 3 hrs worth of riding time. Sometimes I get 4 rides a month just depends. So lets just go with 3 3hr rides per month. And I am able to ride year round mind you. So thats roughly 9hrs of riding a month at a pretty reasonable pace. X's 12 months = 108hrs of riding. That seems like a lot of time and it would be if we all REALLY road as hard as professional racers or even amateur racers. So lets just cut that time in half because thats probably more realistic riding time for me anyways. 54hrs of riding time. Still seems like a lot. But truthfully its not. I like to do a compression test when I install an new piston and before I replace a piston. Now I always replace both piston and rings though I could probably get away with just the rings. Thats just me. Anyways I only have about a 10 PSI difference between new and replacement time. To some that may be alot. But when I was really riding a lot I easily got 100 hrs of ride time a year. Yes that piston and rings needed to be replaced I think the PSI was like high to mid 70s. And the bike performed like it too with 100 hrs of time on it. And the cylinders look fine. Most of the time I just clean them really well. Sometimes I will run a very light grit hone just to bring the cross hatching back.

Now if you remember back in the first paragraph 10rs of ride time per manufacturers spec. Youd be replacing a top end per month. At $100-$200 a shot. I know I cant afford that and Im going to assume most that read this cant or wont either. So realistically yes you can get away with a new top end per year. Providing you keep your bike jetted correctly run the correct oil ratio and quality oils. These are my results. Yours may differ.

Guys with 4T bikes need not comment as 4T bikes can go a very long time between piston and ring swaps. My Brothers 06 KX450 that he bought new out of the crate is still on its original piston and rings. Still has plenty O poop left in it. And he rides way more than I do and is way faster than I am. But he also takes very good care of his machine.
 
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done my first race last month a different bike (profile pic) next h&h in two weeks first on the new bike and another a week or two after that
 
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